Relevant bibliographies by topics / Virus challenge

Academic literature on the topic 'Virus challenge'

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Published: 10 December 2022
Last updated: 28 January 2023

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Journal articles on the topic "Virus challenge"

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Ryan Cross. "Virus variants challenge vaccines." C&EN Global Enterprise 99, no. 4 (February 1, 2021): 4. http://dx.doi.org/10.1021/cen-09904-leadcon.

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Shi, Yi. "New Virus, New Challenge." Innovation 1, no. 1 (May 2020): 100005. http://dx.doi.org/10.1016/j.xinn.2020.04.005.

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Khatissian, Emmanuel, Valérie Monceaux, Marie-Christine Cumont, Marie-Paule Kieny, Anne-Marie Aubertin, and Bruno Hurtrel. "Persistence of Pathogenic Challenge Virus in Macaques Protected by Simian Immunodeficiency Virus SIVmacΔnef." Journal of Virology 75, no. 3 (February 1, 2001): 1507–15. http://dx.doi.org/10.1128/jvi.75.3.1507-1515.2001.

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ABSTRACT Live attenuated simian immunodeficiency virus (SIV) is the most efficient vaccine yet developed in monkey models of human immunodeficiency virus infection. In all successful vaccine trials, attenuation was achieved by inactivating at least the nefgene. We investigated some virological and immunological characteristics of five rhesus macaques immunized with anef-inactivated SIVmac251 molecular clone (SIVmac251Δnef) and challenged 15 months later with the pathogenic SIVmac251 isolate. Three animals were killed 2 weeks postchallenge (p.c.) to search for the challenge virus and to assess immunological changes in various organs. The other two animals have been monitored up for 7 years p.c., with clinical and nefgene changes being noted. The animals killed showed no increase in viral load and no sign of a secondary immune response, although the challenged virus was occasionally detected by PCR. In one of the monkeys being monitored, the vaccine virus persisted and an additional deletion occured in nef. In the other monkey that was monitored, the challenge and the vaccine (Δnef) viruses were both detected by PCR until a virus with a hybrid nefallele was isolated 48 months p.c. This nef hybrid encodes a 245-amino-acid protein. Thus, our results show (i) that monkeys were not totally protected against homologous virus challenge but controlled the challenge very efficiently in the absence of a secondary immune response, and (ii) that the challenge and vaccine viruses may persist in a replication-competent form for long periods after the challenge, possibly resulting in recombination between the two viruses.
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Song, Yufeng, Xiang Wang, Hongbo Zhang, Xinying Tang, Min Li, Jufang Yao, Xia Jin, Hildegund C. J. Ertl, and Dongming Zhou. "Repeated Low-Dose Influenza Virus Infection Causes Severe Disease in Mice: a Model for Vaccine Evaluation." Journal of Virology 89, no. 15 (May 20, 2015): 7841–51. http://dx.doi.org/10.1128/jvi.00976-15.

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ABSTRACTInfluenza infection causes severe disease and death in humans. In traditional vaccine research and development, a single high-dose virus challenge of animals is used to evaluate vaccine efficacy. This type of challenge model may have limitations. In the present study, we developed a novel challenge model by infecting mice repeatedly in short intervals with low doses of influenza A virus. Our results show that compared to a single high-dose infection, mice that received repeated low-dose challenges showed earlier morbidity and mortality and more severe disease. They developed higher vial loads, more severe lung pathology, and greater inflammatory responses and generated only limited influenza A virus-specific B and T cell responses. A commercial trivalent influenza vaccine protected mice against a single high and lethal dose of influenza A virus but was ineffective against repeated low-dose virus challenges. Overall, our data show that the repeated low-dose influenza A virus infection mouse model is more stringent and may thus be more suitable to select for highly efficacious influenza vaccines.IMPORTANCEInfluenza epidemics and pandemics pose serious threats to public health. Animal models are crucial for evaluating the efficacy of influenza vaccines. Traditional models based on a single high-dose virus challenge may have limitations. Here, we describe a new mouse model based on repeated low-dose influenza A virus challenges given within a short period. Repeated low-dose challenges caused more severe disease in mice, associated with higher viral loads and increased lung inflammation and reduced influenza A virus-specific B and T cell responses. A commercial influenza vaccine that was shown to protect mice from high-dose challenge was ineffective against repeated low-dose challenges. Overall, our results show that the low-dose repeated-challenge model is more stringent and may therefore be better suited for preclinical vaccine efficacy studies.
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Mumford, J. A., J. M. Wood, C. Folkers, and G. C. Schild. "Protection against experimental infection with influenza virus A/equine/Miami/63 (H3N8) provided by inactivated whole virus vaccines containing homologous virus." Epidemiology and Infection 100, no. 3 (June 1988): 501–10. http://dx.doi.org/10.1017/s0950268800067236.

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SummaryThirty-one ponies immunized with inactivated virus vaccine containing A/equine/Miami/63 (H3N8) virus and six seronegative ponies were experimentally challenged with the homologous virus strain. All G unvaccinated ponies and 11 out of 31 vaccinated ponies became infected. A clear relationship between pre-challenge antibody, measured by single radial haemolysis (SRH), and protection was demonstrated as judged by virus excretion, febrile responses and antibody responses. Those ponies with SRH antibody levels > 74 mm2 were completely protected against challenge infection by the intranasal route.
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Rahman, Md Rezwanur. "Zika Virus – An Upcoming Challenge?" Delta Medical College Journal 5, no. 1 (February 4, 2017): 1–3. http://dx.doi.org/10.3329/dmcj.v5i1.31416.

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Anderson, Larry J., and Edward E. Walsh. "The Challenge of Respiratory Syncytial Virus Human Challenge Studies." New England Journal of Medicine 386, no. 7 (February 17, 2022): 696–97. http://dx.doi.org/10.1056/nejme2118465.

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McDermott, Adrian B., Jacque Mitchen, Shari Piaskowski, Ivna De Souza, Levi J. Yant, Jason Stephany, Jessica Furlott, and David I. Watkins. "Repeated Low-Dose Mucosal Simian Immunodeficiency Virus SIVmac239 Challenge Results in the Same Viral and Immunological Kinetics as High-Dose Challenge: a Model for the Evaluation of Vaccine Efficacy in Nonhuman Primates." Journal of Virology 78, no. 6 (March 15, 2004): 3140–44. http://dx.doi.org/10.1128/jvi.78.6.3140-3144.2004.

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ABSTRACT Simian immunodeficiency virus (SIV) challenge of rhesus macaques provides a relevant model for the assessment of human immunodeficiency virus (HIV) vaccine strategies. To ensure that all macaques become infected, the vaccinees and controls are exposed to large doses of pathogenic SIV. These nonphysiological high-dose challenges may adversely affect vaccine evaluation by overwhelming potentially efficacious vaccine responses. To determine whether a more physiologically relevant low-dose challenge can initiate infection and cause disease in Indian rhesus macaques, we used a repeated low-dose challenge strategy designed to reduce the viral inoculum to more physiologically relevant doses. In an attempt to more closely mimic challenge with HIV, we administered repeated mucosal challenges with 30, 300, and 3,000 50% tissue culture infective doses (TCID50) of pathogenic SIVmac239 to six animals in three groups. Infection was assessed by sensitive quantitative reverse transcription-PCR and was achieved following a mean of 8, 5.5, and 1 challenge(s) in the 30, 300, and 3,000 TCID50 groups, respectively. Mortality, humoral immune responses, and peak plasma viral kinetics were similar in five of six animals, regardless of challenge dose. Interestingly, macaques challenged with lower doses of SIVmac239 developed broad T-cell immune responses as assessed by ELISPOT assay. This low-dose repeated challenge may be a valuable tool in the evaluation of potential vaccine regimes and offers a more physiologically relevant regimen for pathogenic SIVmac239 challenge experiments.
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Brasel, Trevor, Jason E. Comer, Shane Massey, Jeanon Smith, Jennifer Smith, Matthew Hyde, Andrew Kocsis, et al. "Mucosal Challenge Ferret Models of Ebola Virus Disease." Pathogens 10, no. 3 (March 4, 2021): 292. http://dx.doi.org/10.3390/pathogens10030292.

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Recent studies have shown the domestic ferret (Mustela putorius furo) to be a promising small animal model for the study of Ebola virus (EBOV) disease and medical countermeasure evaluation. To date, most studies have focused on traditional challenge routes, predominantly intramuscular and intranasal administration. Here, we present results from a non-clinical pathogenicity study examining oronasal, oral, and ocular mucosal challenge routes in ferrets. Animals were challenged with 1, 10, or 100 plaque forming units EBOV followed by monitoring of disease progression and biosampling. Ferrets administered virus via oronasal and oral routes met euthanasia criteria due to advanced disease 5–10 days post-challenge. Conversely, all ferrets dosed via the ocular route survived until the scheduled study termination 28-day post-challenge. In animals that succumbed to disease, a dose/route response was not observed; increases in disease severity, febrile responses, serum and tissue viral load, alterations in clinical pathology, and gross/histopathology findings were similar between subjects. Disease progression in ferrets challenged via ocular administration was unremarkable throughout the study period. Results from this study further support the ferret as a model for EBOV disease following oral and nasal mucosa exposure.
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Moser, Charlotte A., Sarah Cookinham, Susan E. Coffin, H. Fred Clark, and Paul A. Offit. "Relative Importance of Rotavirus-Specific Effector and Memory B Cells in Protection against Challenge." Journal of Virology 72, no. 2 (February 1, 1998): 1108–14. http://dx.doi.org/10.1128/jvi.72.2.1108-1114.1998.

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ABSTRACT Adult BALB/c mice were orally inoculated with murine (strain EDIM), simian (strain RRV), or bovine (strain WC3) rotavirus. Six or 16 weeks after inoculation, mice were challenged with EDIM. At the time of challenge and in the days immediately following challenge, production of rotavirus-specific immunoglobulin A (IgA), IgG, and IgM by small intestinal lamina propria lymphocytes (LPL) was determined by fragment culture, and quantities of virus-specific antibodies at the intestinal mucosal surface were determined by intestinal lavage. Mice immunized with EDIM were completely protected against EDIM challenge both 6 and 16 weeks after immunization. Protection was associated with production of high levels of IgA by LPL and detection of virus-specific IgA at the intestinal mucosal surface. In addition, animals immunized and later challenged with EDIM did not develop a boost in antibody responses, suggesting that they were also not reinfected. We also found that in mice immunized with nonmurine rotaviruses, (i) quantities of virus-specific IgA generated following challenge were greater 16 weeks than 6 weeks after immunization, (ii) immunization enhanced the magnitude but did not hasten the onset of production of high quantities of virus-specific IgA by LPL after challenge, and (iii) immunization induced partial protection against challenge; however, protection was not associated with either production of virus-specific antibodies by LPL or detection of virus-specific antibodies at the intestinal mucosal surface.
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Dissertations / Theses on the topic "Virus challenge"

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Carlson, Jolene Christine. "Dynamics of protection against virulent challenge in swine vaccinated with attenuated African swine fever viruses." Diss., Kansas State University, 2016. http://hdl.handle.net/2097/34143.

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Doctor of Philosophy
Department of Diagnostic Medicine/Pathobiology
Manuel Borca
Stephen Higgs
African swine fever (ASF) is a lethal hemorrhagic disease of swine caused by a double-stranded DNA virus. ASFV is endemic in Sardinia and Saharan Africa and has been recently expanded from the Caucasus to Eastern Europe. There is no vaccine to prevent the disease and current control measures are limited to culling and restricted animal movement. Swine infected with attenuated strains are protected against challenge with a homologous virulent virus, but there is limited knowledge of the host immune mechanisms generating that protection. Swine infected with Pret4 virus develop a fatal severe disease, while a derivative strain lacking virulence-associated gene 9GL (Pret4Δ9GL virus) is completely attenuated. Swine infected with Pret4 Δ9GL virus and challenged with the virulent parental virus at 7, 10, 14, 21, and 28 dpi showed a progressive acquisition of protection (from 40% at 7 dpi to 80% at 21 and 28 dpi). This animal model was used to associate the presence of host immune response and protection against the challenge. Anti-ASFV antibodies and cytokines in serum, as well as ASFV-specific IFN-γ production in PBMCs, were assessed in each group. Interestingly, with the exception of ASFV-specific antibodies in the surviving swine challenged at 21 and 28 dpi, no solid association between any of the parameters assessed and the extent of protection could be established. These results were corroborated using a similar model based on the use of a rationally attenuated derivative of the highly virulent strain Georgia 2007. These results, encompassing data from 114 immunized swine, underscore the complexity of the system under study where it is very plausible that protection against disease or infection relies heavily on the concurrence and or interaction of different host immune mechanisms.
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Heskett, Eric A. "Efficacy of a recombinant Herpes Virus of Turkeys vector vaccine, expressing genes to Newcastle disease virus and Marek's disease virus in chickens and turkeys, against exotic Newcastle disease virus challenge." [Gainesville, Fla.] : University of Florida, 2003. http://purl.fcla.edu/fcla/etd/UFE0000700.

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Keckler, M. Shannon. "The role of cytotoxic T lymphocytes in protection from pathogenic simian immunodeficiency virus challenge : a dissertation /." San Antonio : UTHSC, 2007. http://proquest.umi.com/pqdweb?did=1414133541&sid=1&Fmt=2&clientId=70986&RQT=309&VName=PQD.

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Souto, Ricardo Gomes. "Evaluation of cross protection by an attenuated African swine fever virus isolate against heterologous challenge." Diss., University of Pretoria, 2012. http://hdl.handle.net/2263/33369.

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African Swine Fever Virus (ASFV) is an Asfivirus and is the only member of the family Asfarviridae. It manifests as a disease that varies from acute to sub-acute or chronic forms. A true carrier state in domestic pigs is unknown but chronically affected individuals may carry and spread the virus for extended periods. African Swine Fever (ASF) is a socio-economically important disease characterized by high morbidity and mortality affecting the livelihood of many small to big scale farmers and seriously compromising international trade. Strategic measures to control this disease are by physical containment and culling in outbreak situations. There is no vaccine available. Nevertheless, every pork producer should ideally be actively involved in having biosecurity measures in place to avoid contamination and contacting their veterinary services in case of suspicion of ASF to have appropriate samples analysed. Official veterinary services must be equipped with proper diagnostic tools in order to provide a quick response. The sensitivity of currently available diagnostic tests at the Transboundary Animal Diseases Programme, Onderstepoort Veterinary Institute was analysed in order to report the best technique available. Sensitivity to ASF virus infection and therefore diagnostic potential of cell primary cultures as bone marrow macrophages, blood macrophages and alveolar macrophages was done via comparison of titre results from inoculations of ASFV SPEC 257 as control, and ASFV MOZ 1/98. In addition, molecular detection of specific DNA fragments within the viral genome were compared using five different PCRs. Bone marrow macrophage cultures and blood macrophage cultures were the most reliable cells whereas alveolar macrophages more often showed contamination. Results show that PPA PCR and real time PCR detected the highest diluted samples, thus the lowest concentration of virus, in both trials done with ASFV MOZ 1/98 and ASFV SPEC 257. In addition, animal trials were performed by inoculating domestic pigs with four different ASFV isolates of varying pathogenicity. These viruses were all from distinct geographic origins. Non-virulent ASFV OURT 3/88 and high virulent ASFV BENIN 1/97 were previously described and used as reference viruses. ASFV MOZ 1/98, suspected of having high virulence and ASFV MKUZE, which was thought to be of low virulence were included in this study to provide further information on the pathological and clinical outcome of the disease as well as measuring viral replication in various organs and blood. The study showed that ASFV MKUZE was of intermediate virulence, whilst ASFV MOZ 1/98 was highly virulent with a high mortality rate. Results confirmed the inadequacy of ASFV MKUZE to act as vaccine opposed to ASFV OURT 3/88. Following this, a potential vaccine by use of attenuated Portuguese ASFV OURT 3/88 tested against virulent heterologous challenge with a strain now known with certainty to cause acute ASF, the isolate ASFV MOZ 1/98 collected from a diseased pig in Mozambique. Domestic commercial pigs where submitted to either one or two vaccinations before challenge. Viral load in blood and tissue samples was higher in unvaccinated animals and higher in single vaccinated than in pigs vaccinated twice. However, acute ASF afflicted all groups with severe clinical signs and post-mortem lesions. Although it did not confer total immunity it was determined that pigs vaccinated with European attenuated ASFV OURT 3/88 acquired partial protection against challenge with virulent southern Africa ASFV MOZ 1/98.
Dissertation (MSc)--University of Pretoria, 2012.
gm2014
ab2015
Veterinary Tropical Diseases
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Laforce, Wendy Marie. "The effect of vaccinia virus challenge and adjuvant induced arthritis on chemokine receptor expression by rat leukocytes." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape4/PQDD_0016/MQ57202.pdf.

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Regnard, Guy Louis. "Development of a potential challenge model and plant-produced vaccine candidate for beak and feather disease virus." Doctoral thesis, University of Cape Town, 2015. http://hdl.handle.net/11427/15690.

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Psittacine beak and feather disease (PBFD), the most prevalent viral disease affecting psittacines, is caused by beak and feather disease virus (BFDV). An outbreak of the disease has been reported in wild endangered Cape parrots (Poicephalus robustus), which is endemic to South Africa. No treatment or vaccine is commercially available. In this study, an investigation into the outbreak was undertaken. BFDV diversity was assessed and viral load and clinical signs correlated. A plant-produced BFDV subunit vaccine was produced in parallel with a corresponding challenge model. Cape parrots were assessed and 53 blood samples collected. Viral load was determined using quantitative real-time PCR (qPCR), and 22 BFDV full-length genome sequences acquired to infer phylogenetic relatedness. The capsid gene (cp) was optimised for transient Agrobacterium-mediated expression in whole-plant Nicotiana benthamiana (N. benthamiana). Virus-like particles (VLPs) were purified and analysed using transmission electron microscopy. Virions from a Palm cockatoo (Probosciger aterrimus) were purified and a BFDV dsDNA molecular clone was synthesised and replication assessed in 293TT mammalian cells and N. benthamiana using rolling circle replication and qPCR. Two distinct BFDV phylogenetic clusters were reported for Cape parrots, and a direct correlation was seen between viral load in the blood and clinical signs in PBFD-afflicted birds. The CP was successfully expressed in N. benthamiana, and increased through optimisation of Agrobacterium infiltration density and the inclusion of the NSs silencing suppressor. The CP formed VLPs, which were shown to be morphologically similar to infectious virions. The dsDNA molecular clone was shown to replicate autonomously in mammalian 293TT cells, and in plants with the assistance of the Bean yellow dwarf virus replication associated protein (Rep). BFDV genetic diversity in Cape parrots highlights the importance of ensuring new strains are not inadvertently introduced into the wild. This is the first systematic investigation of virus diversity in Cape parrots and assessment of BFDV viral load in a wild psittacine population. The CP was successfully produced in planta and presence of VLPs suggests the possibility of developing pseudovirions. This is the first reported replication of BFDV in tissue culture, and will greatly expand the scope of available research.
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Niederwerder, Megan C. "Clinical disease and host response of nursery pigs following challenge with emerging and re-emerging swine viruses." Diss., Kansas State University, 2015. http://hdl.handle.net/2097/20491.

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Doctor of Philosophy
Diagnostic Medicine/Pathobiology
Raymond R. R. Rowland
Emerging viral diseases cause significant and widespread economic losses to U.S. swine production. Over the last 25 years, porcine reproductive and respiratory syndrome virus (PRRSV), porcine circovirus type 2 (PCV2) and porcine epidemic diarrhea virus (PEDV) have emerged or re-emerged, costing the industry billions through increased mortality and clinical or subclinical reductions in growth. Nursery pigs are greatly affected by these viruses due to high susceptibility to primary and secondary infections after weaning. However, clinical disease occurs in only a subpopulation of infected pigs and can vary drastically from sudden death to poor growth performance. This thesis documents a series of 4 studies where nursery pigs were challenged with either PRRSV/PCV2 or PEDV; the associations between clinical outcome and several factors affecting viral pathogenesis were investigated. In the first study, the administration of PRRS modified live virus vaccine prior to co-challenge with PRRSV/PCV2 was shown to protect against PRRS but enhance PCV2 replication and pathogenesis. This study provides insight into the role that PRRS vaccination has in both the control and potentiation of clinical disease. In the second study, microbial populations were compared between pigs with the best and worst clinical outcome following PRRSV/PCV2 co-infection. Increased fecal microbiome diversity was associated with improved clinical outcome; however, worst clinical outcome pigs had prolonged and greater virus replication, highlighting the host response to viral challenge as a primary determinant of clinical outcome. In the third study, 13 clinical phenotypes were compiled for >450 pigs after PRRSV/PCV2 co-infection. Duration of dyspnea and the presence of muscle wasting had the strongest associations with reduced weight gain. This study highlights the opportunity to improve animal welfare and production through improvements in clinical health. In the fourth study, clinical disease was mild to moderate and occurred within the first week after pigs were challenged with PEDV. However, PEDV was detected weeks after clinical disease had resolved and may implicate nursery pigs as an important source of viral carriage and transmission. Overall, the goal of this thesis was to develop models for understanding the impact of emerging and re-emerging viruses to improve recognition and control of disease.
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Ashok, M. S. "Evaluation Of The Efficacy Of DNA Vaccines For Japanese Encephalitis In A Murine Intracerebral Japanese Encephalitis Virus Challenge Model." Thesis, Indian Institute of Science, 2000. http://hdl.handle.net/2005/169.

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Japanese encephalitis virus (JEV), a member of the family flaviviridae, is one of the most important pathogens of the developing countries, causing high mortality and morbidity amongst children. The present study is aimed at the development of a DNA vaccine for Japanese Encephalitis (JE). As a first step towards developing a DNA vaccine for JE, an eukaryotic expression plasmid encoding the envelope (E) glycoprotein of Japanese Encephalitis Virus (pCMXENV) was constructed. This plasmid expresses the E protein intracellularly, when transfected into Vero cells in culture. Several independent immunization and intracerebral (i.e.) JEV challenge experiments were carried out and the results indicate that 51% and 59% of the mice are protected from lethal i.e. JEV challenge, when immunized with pCMXENV via intramuscular (i.m.) and intranasal (i.n.) routes respectively. JEV-specific antibodies were not detected in pCMXENV-immunized mice either before or after challenge. JEV-specific T cells were observed in mice immunized with pCMXENV, which increased significantly after JEV challenge indicating the presence of vaccination-induced memory T cells. Enhanced production of interferon-y (EFN-y) and complete absence of interleukin-4 (IL-4) in splenocytes of pCMXENV-immunized mice on restimulation with JEV antigens in vitro indicated that the protection is likely to be mediated by T helper (Th) lymphocytes of the Thl sub type. These results demonstrated that immunization with a plasmid DNA expressing intracellular form of JEV E protein confers significant protection against i.e. JEV challenge even in the absence of detectable antiviral antibodies. We then examined the potency of JEV DNA vaccines as well as that of the inactivated mouse brain derived BIKEN vaccine in the i.e. challenge model. The results indicate that all the mice immunized with BIKEN JE vaccine were protected against i.e. JEV challenge while 50% protection was observed in case of mice immunized with pJME or pJNSl and 38% protection was observed in pCMXENV-immunized mice. Immunization with both pJME and pJNSl resulted in 66% protection. These results indicate that the BIKEN JE vaccine confers better protection against i.e. JEV challenge than DNA vaccines. The fact that the BIKEN vaccine conferred better protection against i.e. JEV challenge than DNA vaccines indicated that the i.e. JEV challenge model can be exploited further to examine the potency of different DNA vaccine constructs. Towards this goal, we constructed plasmids that encode secretory or nonsecretory forms of JEV E protein and examined their potency in the i.e. JEV challenge model. Our results indicate that i.m. immunization of mice with plasmid encoding secretory form of JEV E protein confers higher level (75%-80%) protection than those encoding nonsecretory forms. Cytokine analysis of splenocytes isolated from DNA immunized mice after stimulation in vitro with JEV revealed that immunization with plasmid encoding secretory form of JEV E protein induces both Thl and Th2 responses while those encoding nonsecretory forms induce only Thl type of response. Thus, synthesis of secretory form of JEV E protein results in an altered immune response leading better protection against i.e. JEV challenge. Based on our studies, we propose that both cellular and humoral immune responses play a key role in protective immunity against i.e. JEV challenge and DNA vaccines that can induce higher levels of neutralizing antibodies will be as efficient as the BIKEN vaccine in conferring protection against i.e. JEV challenge.
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Osuagwuh, Uchebuchi I. "Semen quality and the excretion of lumpy skin disease virus in semen following vaccination and experimental challenge of vaccinated bulls." Diss., University of Pretoria, 2006. http://hdl.handle.net/2263/23607.

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The aim of this study was to determine the efficacy of vaccination in preventing LSDV excretion in semen and negative effects on semen quality. Lumpy skin disease (LSD) is caused by a virus in the genus Capripoxvirus of the family Poxviridae. The virus has been reported to be excreted in the semen of experimental infected nonvaccinated bulls. Nevertheless, vaccination has been the most widely used method to reduce and prevent the spread of the disease. This work was done to determine the efficacy of lumpy skin disease vaccination in preventing the excretion of lumpy skin disease virus (LSDV) in semen of experimentally infected vaccinated bulls. It also determined further the effect of vaccination and experimental infection on semen quality. Six serologically negative bulls 11-16 months of age were vaccinated with an attenuated Neethling strain of LSD vaccine, and a repeated dose of vaccine was given twenty one days later. These bulls were then experimentally infected by intravenous injection with a virulent field strain of LSDV (V248/93). Six unvaccinated bulls were similarly infected to act as controls. All animals were observed for clinical signs, blood and semen was collected and evaluated twice a week until day 40 post vaccination and every two days until day 28 post-infection when the trial was terminated. Serology was done using the serum neutralization test and viraemia was determined by virus isolation. Semen was examined by polymerase chain reaction (PCR) for the presence of virus. Semen evaluation was done visually and microscopically. Two of the unvaccinated controls developed severe LSD, two showed mild symptoms and two were asymptomatic. No clinical abnormalities were detected following vaccination, and clinical signs were limited to mild lymph node enlargement in four bulls following challenge of the vaccinated bulls. There was a significant difference (P<0.05) in semen quality after experimental infection of the unvaccinated bulls. In the vaccinated bulls, semen quality showed no significant difference (P>0.05) following vaccination and challenge. Three of the vaccinated bulls were serologically positive at the time of experimental infection and four at the end of the trial. Five unvaccinated bulls were found to be viraemic during the course of the trial. No vaccinated bulls were found to be viraemic at any stage. Four unvaccinated bulls excreted the virus in their semen during the course of the trial. Viral nucleic acid was not detected in any semen samples following vaccination or challenge in vaccinated bulls. This study provides evidence that vaccination against LSD prevented the excretion of viral particles in semen. It also illustrated that LSD vaccination prevented any effect on semen quality after experimental infection with virulent virus.
Dissertation (MSc (Production Animal Studies))--University of Pretoria, 2006.
Production Animal Studies
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Soko, Misheck Mica Mafeni. "Evaluation of transgenic RNAi banana and plantain lines for resistance to banana bunchy top disease." Thesis, Queensland University of Technology, 2022. https://eprints.qut.edu.au/228515/1/Misheck%20Mica%20Mafeni_Soko_Thesis.pdf.

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This project evaluated genetically modified Cavendish bananas and plantains for field and glasshouse resistance to banana bunchy top virus in Malawi in Africa, over a three-and-a-half-year period. The study identified several GM lines with significant resistance to the virus and provided a rare insight into virus-vector relations and the climate. The research showed that rigorous field assessment of GM plants for disease resistance is critical and that immunity to this virus will likely only be achieved using a multi-faceted resistance strategy.
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Books on the topic "Virus challenge"

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Rochelle, Paul A. Challenge organisms for inactivation of viruses by ultraviolet treatment. Denver, Colo: Water Research Foundation, 2010.

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Anderson, Larry J., and Barney S. Graham, eds. Challenges and Opportunities for Respiratory Syncytial Virus Vaccines. Berlin, Heidelberg: Springer Berlin Heidelberg, 2013. http://dx.doi.org/10.1007/978-3-642-38919-1.

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1955-, Smith Geoffrey L., and Society for General Microbiology, eds. New challenges to health: The threat of virus infection. Cambridge: Cambridge University Press, 2001.

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G, Koopmans M. P., Cliver Dean O, and Bosch Albert, eds. Food-borne viruses: Progress and challenges. Washington, DC: ASM Press, 2008.

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Institute of Medicine (U.S.). Forum on Microbial Threats, ed. The domestic and international impacts of the 2009-H1N1 influenza a pandemic: Global challenges, global solutions : workshop summary. Washington, D.C: National Academies Press, 2010.

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United States. Congress. House. Committee on Government Reform. Subcommittee on Energy Policy, Natural Resources, and Regulatory Affairs. Current challenges in combating the West Nile virus: Hearing before the Subcommittee on Energy Policy, Natural Resources, and Regulatory Affairs of the Committee on Government Reform, House of Representatives, One Hundred Eighth Congress, second session, October 6, 2004. Washington: U.S. G.P.O., 2005.

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Williams, Spensha. 30 Days Fitness Challenge - the Deadliest Virus in America Is the Media AntiMedia. Independently Published, 2021.

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Drennan, John D. DNA vaccines encoding the glycoprotein genes of spring viremia of carp virus, snakehead rhabdovirus, or infectious hematopoietic necrosis virus induce protective immunity in rainbow trout (Oncorhynchus mykiss) against an infectious hematopoietic necrosis virus lethal challenge. 1998.

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Anderson, Larry J., and Barney S. Graham. Challenges and Opportunities for Respiratory Syncytial Virus Vaccines. Springer London, Limited, 2013.

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Anderson, Larry J., and Barney S. Graham. Challenges and Opportunities for Respiratory Syncytial Virus Vaccines. Springer, 2013.

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Book chapters on the topic "Virus challenge"

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Rapp, F. "The Challenge of Chronic Virus Infections." In Frontiers in Microbiology, 191–206. Dordrecht: Springer Netherlands, 1987. http://dx.doi.org/10.1007/978-94-009-3353-8_18.

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Kurth, Andreas, and Andreas Nitsche. "Epidemic Cowpox Virus Infections in Germany." In The Challenge of Highly Pathogenic Microorganisms, 157–64. Dordrecht: Springer Netherlands, 2010. http://dx.doi.org/10.1007/978-90-481-9054-6_16.

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Smith, Geoffrey L. "Inhibitors of Innate Immunity from Vaccinia Virus." In The Challenge of Highly Pathogenic Microorganisms, 125–34. Dordrecht: Springer Netherlands, 2010. http://dx.doi.org/10.1007/978-90-481-9054-6_13.

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Israely, Tomer, Sharon Melamed, Noam Erez, Boaz Politi, Udy Olshevsky, Reuven Levin, Shlomo Lustig, and Nir Paran. "MMP-9 as a Marker for Vaccinia Virus Related Encephalitis." In The Challenge of Highly Pathogenic Microorganisms, 147–55. Dordrecht: Springer Netherlands, 2010. http://dx.doi.org/10.1007/978-90-481-9054-6_15.

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Lehmann, Michael H., Melanie Kremer, Yasemin Suezer, and Gerd Sutter. "Modified Vaccinia Virus Ankara (MVA) based Vaccines – Immunostimulatory and Protective Capacity." In The Challenge of Highly Pathogenic Microorganisms, 245–51. Dordrecht: Springer Netherlands, 2010. http://dx.doi.org/10.1007/978-90-481-9054-6_26.

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Paran, Nir, Shlomo Lustig, Anat Zvi, Tomer Israely, Sharon Melamed, Noam Erez, Boaz Politi, et al. "Role of A33R Amino-Acid 118L in the Interactions of Vaccinia Virus with the Host." In The Challenge of Highly Pathogenic Microorganisms, 115–23. Dordrecht: Springer Netherlands, 2010. http://dx.doi.org/10.1007/978-90-481-9054-6_12.

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Kreuze, Jan, Wilmer J. Cuellar, and Jan W. Low. "Challenge of Virus Disease Threats to Ensuring Sustained Uptake of Vitamin-A-Rich Sweetpotato in Africa." In Plant Diseases and Food Security in the 21st Century, 73–94. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-57899-2_5.

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AbstractOrange-fleshed sweetpotatoes (OFSP) are a rich source of pro-vitamin A and can alleviate vitamin A deficiency in the developing world. In Africa, traditional varieties have been almost exclusively white-fleshed and introduction and breeding of orange-fleshed varieties into Africa has been severely hampered by virus diseases to which many varieties are susceptible. Breeding progress to generate resistant varieties has been slow due to rare and recessive occurrence of resistance in breeding populations. Production of virus-free seed is complicated by the fact that most sweetpotato viruses show no or only limited symptoms and very low virus concentrations when infected by individual viruses, making them difficult to detect. Even single infections can lead to significant yield losses, but when they combine severe disease complexes are generated, which can lead to total crop failure. Significant efforts have been made in characterizing and understanding virus interactions in sweetpotato over the last two decades to address this challenge; they are reviewed in this chapter. We also review the state of the art in detection of viruses in support of seed systems and breeding. We conclude with recommendations for the most urgent future research directions needed to address virus problems in sweetpotatoes.
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Boin, Arjen, Allan McConnell, and Paul ‘t Hart. "The Year of the Unthinkable." In Governing the Pandemic, 1–17. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-72680-5_1.

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AbstractCOVID-19 brought the ‘unthinkable’ to our doorstep. The pandemic caused a series of global, and interconnected, health, economic, social, institutional and political crises that are unprecedented in living memory. Political leaders struggled to contain the virus and persuade anxious, weary citizens to behave this or that way in order to overcome a giant collective action problem. This chapter is a primer for the detailed examination of political and policy responses to this impossible challenge. It describes pivotal governance challenges and the constraints operating on the crisis response.
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Minke, J. M., L. Siger, K. Karaca, L. Austgen, P. Gordy, R. Bowen, R. W. Renshaw, S. Loosmore, J. C. Audonnet, and B. Nordgren. "Recombinant canarypoxvirus vaccine carrying the prM/E genes of West Nile virus protects horses against a West Nile virus-mosquito challenge." In Emergence and Control of Zoonotic Viral Encephalitides, 221–30. Vienna: Springer Vienna, 2004. http://dx.doi.org/10.1007/978-3-7091-0572-6_20.

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Barthold, Stephen W., and Deborah S. Beck. "Intranasal Challenge Immunity of Mice to Antigenically Homologous and Heterologous Strains of Mouse Hepatitis Virus." In Coronaviruses, 449–50. Boston, MA: Springer US, 1987. http://dx.doi.org/10.1007/978-1-4684-1280-2_55.

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Conference papers on the topic "Virus challenge"

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Urassa, Hija. "CORONA VIRUS PANDEMIC: CHALLENGE TO THE ADVANCED SECONDARY SCHOOL CANDIDATES IN TANZANIA." In 13th annual International Conference of Education, Research and Innovation. IATED, 2020. http://dx.doi.org/10.21125/iceri.2020.1546.

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Nakayama, M., H. Ishigaki, N. Thanh Cong, S. Suzuki, H. Ishida, N. Kitagawa, K. Ogasawara, and Y. Itoh. "Long-term efficacy of an inactivated whole particle H5N1 virus against H5N1 highly pathogenic avian influenza virus challenge in cynomolgus monkeys." In ERS International Congress 2022 abstracts. European Respiratory Society, 2022. http://dx.doi.org/10.1183/13993003.congress-2022.662.

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Flores Anticona, Edgardo M., Hadeel Zainah, Laura Johnson, and Daniel Ouellette. "West Nile Virus Neuroinvasive Disease In The Critical Care Unit: A Diagnostic Challenge." In American Thoracic Society 2012 International Conference, May 18-23, 2012 • San Francisco, California. American Thoracic Society, 2012. http://dx.doi.org/10.1164/ajrccm-conference.2012.185.1_meetingabstracts.a5943.

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Bell, Alan, Michael Ghebre, Graham Clarke, Rob Lambkin Williams, Andrew Catchpole, and Nicolas Noulin. "Pattern of self-reported (cough focus) symptoms across several respiratory virus- human challenge studies." In ERS International Congress 2018 abstracts. European Respiratory Society, 2018. http://dx.doi.org/10.1183/13993003.congress-2018.pa5464.

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Worrell, Julie, George Finney, Kerrie Hargrave, Chris Hansell, Jagtar Singh-Nijjar, Fraser Morton, John Cole, and Megan Macleod. "Exploring the role of infection experienced lung stromal cells following re-challenge with influenza A virus." In ERS Lung Science Conference 2022 abstracts. European Respiratory Society, 2022. http://dx.doi.org/10.1183/23120541.lsc-2022.17.

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Milovanović, Ana. "Mogućnosti i izazovi nastave dramske umetnosti u izmenjenom društvenom kontekstu." In Nauka, nastava, učenje u izmenjenom društvenom kontekstu. University of Kragujevac, Faculty of Education in Uzice, 2021. http://dx.doi.org/10.46793/nnu21.189m.

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The subject of the paper are the possibilities and challenges of teaching drama in a changed social context. In the social context changed by the application of the agenda of globalism in Serbian education, the teaching of drama for preschool teachers begins to lose quality at university. Due to the specific nature of drama as art, online teaching of this subject is not possible. Research of teaching the subject Drama and Movement at the Teacher Education Faculty in Belgrade was shown that teaching was limited to lectures and theoretical exercises during the state of emergency, and that practical exercises were necessary after its abolition. An insurmountable challenge was the protection measures against the corona virus, as a result of which it was impossible to hold exercises of puppet animation and puppet directing, ie to prepare puppet shows (except monodramas). High engagement of professor was necessary for the quality of teaching.
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Kulmanis, Oskars. "Taisnīga kriminālprocesa norise ārkārtas situācijā." In The 8th International Scientific Conference of the Faculty of Law of the University of Latvia. University of Latvia Press, 2022. http://dx.doi.org/10.22364/iscflul.8.1.16.

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The global spread of Covid-19 virus has significantly affected the continuous operation of courts in criminal proceedings and spurred changes to justice systems. The court system of Republic of Latvia is no exception. Since the adoption of Law on the Management of the Spread of Covid-19 Infection, securing a fair trial in criminal proceedings has been a great challenge. The paper addresses proportionality of use of written procedure as one of the main procedural forms to try a criminal case in court of appeal.
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Reis, Luana Brandão de Sales, Beatriz do Nascimento Garcia Moreno, Ricardo Moreno do Carmo Junior, João Guilherme Santos Garrido, and João Gustavo dos Anjos Morais Oliveira. "Elucidating the relationship between meningitis and SARSCoV-2 infection: a literature review." In XIII Congresso Paulista de Neurologia. Zeppelini Editorial e Comunicação, 2021. http://dx.doi.org/10.5327/1516-3180.622.

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Background: The Covid-19 pandemic has become a major challenge for public health, once this disease can even affect the nervous system, causing severe conditions, such as meningitis. The association between meningitis and Covid- 19 is not yet well established, but it is believed that it can be caused both by a bacterial co-infection or by the involvement of meninges due to the action of the virus itself. Objective: The aim of the present study is to elucidate the relationship between meningitis and SARS-CoV-2 infection. Methods: In order to carry out a literature review, case reports were searched in the PUBMED database, in which only articles in English were considered, without year restriction, resulting in the following research formula: “((COVID-19) OR (SARS-CoV-2)) AND (meningitis)”. Results: 33 case reports were found, of which only 12 met the eligibility criteria. The reported cases provide evidence of meningeal and brain involvement by the SARS-CoV-2 virus, some with confirmation by CSF RT-PCR. Isolation of the SARS-CoV-2 virus in the CSF is challenging and has not been possible in other patients; however, the exclusion of bacterial involvement by culture and other viral agents in the CSF analysis points to infection by SARS-CoV-2 in a patient with positive RT-PCR by nasopharyngeal swab or bronchoalveolar lavage. Conclusions: The possibility of SARS-CoV-2 meningitis reinforces the need to investigate this condition in patients with COVID-19 who have neurological symptoms.
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Maksimović, Jelena, Nedeljko Milanović, and Jelena Osmanović Zajić. "Samo(procena) nastavnika o kvalitetu onlajn nastave tokom pandemije kovid-19." In Nauka, nastava, učenje u izmenjenom društvenom kontekstu. University of Kragujevac, Faculty of Education in Uzice, 2021. http://dx.doi.org/10.46793/nnu21.231m.

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The COVID-19 virus pandemic also had a significant impact on the educational system. This article presents the results of a research aimed at examining teachers' attitudes about the quality of online teaching during the COVID-19 virus pandemic. A descriptive research method and survey technique were applied. The sample included 274 teachers from the territory of the Republic of Serbia. The presented results indicate that the largest number of teachers with online teaching met for the first time during the pandemic and that until then they had no experience with distance learning. The platforms most often used by teachers in working with students are: Google Classroom, Zoom, Edmodo, Google Meet and Microsoft Teams. Also, a large number of teachers answered that they will partially apply online teaching after the pandemic, emphasizing that contact teaching is irreplaceable and of much higher quality, because students are more engaged, prepared and committed to school obligations. Looking at it objectively, teachers most often rated the quality of online teaching during the pandemic as average, more precisely with a grade of three. Online teaching during the pandemic required great dedication and teacher engagement, as well as good management of information and communication technologies and developed digital competencies of both teachers and students. The realization of online teaching was a challenge for teachers, but also the only possibility and solution to continue and actively carry out educational work during the pandemic and emergency situation.
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Lukinović, Mario, Larisa Jovanović, and Vladimir Šašo. "CHALLENGES IN MANAGING INTELLECTUAL PROPERTY RIGHTS DURING CORONAVIRUS PANDEMIC." In Fourth International Scientific Conference ITEMA Recent Advances in Information Technology, Tourism, Economics, Management and Agriculture. Association of Economists and Managers of the Balkans, Belgrade, Serbia, 2020. http://dx.doi.org/10.31410/itema.2020.239.

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The socio-economic impact of the pandemic on all social spheres is huge, but like any crisis, for some it is an opportunity to create, develop and promote solutions. The coronavirus pandemic has brought many changes. It has forced us all to find new ways of working, interacting and living. The field of intellectual property is particularly affected by the coronavirus pandemic, its strong influence has affected all branches of intellectual property, especially the field of copyright and patents. During the COVID-19 Pandemic, numerous anomalies in the consumption of copyrights were observed, which coincided with the isolation measures, from drastically increased consumption of illegal pirated content via the Internet, especially in countries with lockdown, through a sharp increase of Disney+ and Netflix streaming platform users. The identification of products that have the word Corona in their name – in their trademark, with the virus has led to a sharp drop in consumption of some products, but also to increased sales of others. The pharmaceutical industry has invested huge funds in the fight against this global challenge, especially in the field of treatment of viruses, new drugs for the prevention, as well as finding a vaccine against COVID-19. This paper discusses the challenges faced by the management of intellectual property rights and potential response measures.
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Reports on the topic "Virus challenge"

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Lan, Xi, John C. F. Hsieh, Haibo Liu, Susan J. Lamont, and Qing Zhu. Integration of Host and Virus Gene Expression for Chickens Response to Avian Leukosis Virus Challenge. Ames (Iowa): Iowa State University, January 2018. http://dx.doi.org/10.31274/ans_air-180814-388.

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Mogler, Mark, D. L. Hank Harris, Matthew M. Erdman, and Kurt I. Kamrud. Replicon Particle Porcine Reproductive and Respiratory Syndrome Virus Vaccine Provides Partial Protection from Challenge. Ames (Iowa): Iowa State University, January 2009. http://dx.doi.org/10.31274/ans_air-180814-23.

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Eisley, Christopher J., Eric R. Fritz-Waters, Igseo Choi, James Eugene Koltes, Nicholas Boddicker, James M. Reecy, Joan Lunney, et al. Analysis of Gene Expression in a Region Associated with Host Response to Porcine Reproductive and Respiratory Syndrome Virus Challenge. Ames (Iowa): Iowa State University, January 2014. http://dx.doi.org/10.31274/ans_air-180814-1203.

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Loy, Duan S., Lyric C. Bartholomay, and D. L. Hank Harris. In Vivo Titration and Development of a Challenge Model for White Spot Syndrome Virus (WSSV) in Pacific White Shrimp (Litopeneus vannamei). Ames (Iowa): Iowa State University, January 2011. http://dx.doi.org/10.31274/ans_air-180814-1052.

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Wasi, Chantapong. Virus Diseases: The Global Challenge to Health for All. Asia-Pacific Congress of Medical Virology (2nd) Held in Bangkok, Thailand on November 17-22, 1991. Abstracts. Fort Belvoir, VA: Defense Technical Information Center, July 1992. http://dx.doi.org/10.21236/ada258158.

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DeJong, Jocelyn. A question of scale? The challenge of expanding the impact of non-governmental organisations' HIV/AIDS efforts in developing countries. Population Council, 2001. http://dx.doi.org/10.31899/hiv2001.1003.

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There are currently more than 36 million people living with HIV/AIDS globally, and in 1999 5.3 million individuals were newly infected with the virus. AIDS activities initiated by nongovernmental organizations (NGOs) have been highly influential on thinking and strategies found within the HIV/AIDS sector. Yet NGOs often experience particular difficulties in increasing the scale of their activities to reach larger numbers of people, to have an impact at levels higher than the community, and to address the broader social determinants of HIV/AIDS. Perceiving the urgent need for NGOs to expand the scale of their activities in the face of an escalating epidemic, Horizons and the International HIV/AIDS Alliance launched an initiative to examine the nature of the challenge to scale up in the context of HIV/AIDS internationally. This publication was prepared as part of this initiative and addresses the specific challenge of deliberately increasing the scale of HIV/AIDS prevention, care, and support programs in developing countries.
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DeMartini, James C., Abraham Yaniv, Jonathan O. Carlson, Arnona Gazit, Leonard E. Pearson, Kalman Perk, J. K. Young, Noam Safran, and A. Friedman. Evaluation of Naked Proviral DNA as a Vaccine for Ovine Lentivirus Infection. United States Department of Agriculture, September 1994. http://dx.doi.org/10.32747/1994.7570553.bard.

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Ovine lentivirus (OvLV) infection is widespread in sheep of the United States and Israel and is responsible for substantial economic losses. The primary goal of this project was to evaluate naked proviral DNA as a vaccine to induce protective immunity in sheep in endemic areas. Contrary to expectations, inoculation of sheep with proviral DNA derived from the full length OvLV molecular clone pkv72 did not result in detectable OvLV infection, but infectious virus was recovered from transfected ovine cells. Kv72 virus produced by these cells infected sheep and induced antibody responses, and was used as a viral challenge in subsequent experiments. To improve in vivo transfection efficiency and compare the viral LTR with other romoters, expression of reporter genes was studied in sheep transfected in vivo by injection of cationic liposome-DNA complexes; one formulation produced gene expression in a sheep for 4 months following a single intravenous injection. Since the pol-deleted OvLV construct was not stable in vivo, twelve lambs were injected with plasmids containing the Kv72 gag region (pCMVgag) or env region (pCMVenv), or saline. Prior to challenge, no detectable anti-OvLV immune responses were detected. Following homologous challenge with OvLV. Although the naked DNA approach to vaccination holds promise for control of ovine lentivirus-induced disease, further work needs to be done to develop more effective methods of transfecting sheep with DNA.
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Gelb, Jr., Jack, Yoram Weisman, Brian Ladman, and Rosie Meir. Identification of Avian Infectious Brochitis Virus Variant Serotypes and Subtypes by PCR Product Cycle Sequencing for the Rational Selection of Effective Vaccines. United States Department of Agriculture, December 2003. http://dx.doi.org/10.32747/2003.7586470.bard.

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Objectives 1. Determine the serotypic identities of 40 recent IBV isolates from commercial chickens raised in the USA and Israel. 2. Sequence all IBV field isolates using PCR product cycle sequencing and analyze their S 1 sequence to detennine their homology to other strains in the Genbank and EMBL databases. 3. Select vaccinal strains with the highest S 1 sequence homology to the field isolates and perform challenge of immunity studies in chickens in laboratory trials to detennine level of protection afforded by the vaccines. Background Infectious bronchitis (IB) is a common, economically important disease of the chicken. IB occurs as a respiratory form, associated with airsacculitis, condemnation, and mortality of meat-type broilers, a reproductive form responsible for egg production losses in layers and breeders, and a renal form causing high mortality in broilers and pullets. The causative agent is avian coronavirus infectious bronchitis virus (IBV). Replication of the virus' RNA genome is error-prone and mutations commonly result. A major target for mutation is the gene encoding the spike (S) envelope protein used by the virus to attach and infect the host cell. Mutations in the S gene result in antigenic changes that can lead to the emergence of variant serotypes. The S gene is able to tolerate numerous mutations without compromising the virus' ability to replicate and cause disease. An end result of the virus' "flexibility" is that many strains of IBV are capable of existing in nature. Once formed, new mutant strains, often referred to as variants, are soon subjected to immunological selection so that only the most antigenically novel variants survive in poultry populations. Many novel antigenic variant serotypes and genotypes have been isolated from commercial poultry flocks. Identification of the field isolates of IBV responsible for outbreaks is critical for selecting the appropriate strain(s) for vaccination. Reverse transcriptase polymerase chain reaction (RT-PCR) of the Sl subunit of the envelope spike glycoprotein gene has been a common method used to identify field strains, replacing other time-consuming or less precise tests. Two PCR approaches have been used for identification, restriction fragment length polymorphism (RFLP) and direct automated cycle sequence analysis of a diagnostically relevant hypervariab1e region were compared in our BARD research. Vaccination for IB, although practiced routinely in commercial flocks, is often not protective. Field isolates responsible for outbreaks may be unrelated to the strain(s) used in the vaccination program. However, vaccines may provide varying degrees of cross- protection vs. unrelated field strains so vaccination studies should be performed. Conclusions RFLP and S1 sequence analysis methods were successfully performed using the field isolates from the USA and Israel. Importantly, the S1 sequence analysis method enabled a direct comparison of the genotypes of the field strains by aligning them to sequences in public databases e.g. GenBank. Novel S1 gene sequences were identified in both USA and Israel IBVs but greater diversity was observed in the field isolates from the USA. One novel genotype, characterized in this project, Israel/720/99, is currently being considered for development as an inactivated vaccine. Vaccination with IBV strains in the US (Massachusetts, Arkansas, Delaware 072) or in Israel (Massachusetts, Holland strain) provided higher degrees of cross-protection vs. homologous than heterologous strain challenge. In many cases however, vaccination with two strains (only studies with US strains) produced reasonable cross-protection against heterologous field isolate challenge. Implications S1 sequence analysis provides numerical similarity values and phylogenetic information that can be useful, although by no means conclusive, in developing vaccine control strategies. Identification of many novel S1 genotypes of IBV in the USA is evidence that commercial flocks will be challenged today and in the future with strains unrelated to vaccines. In Israel, monitoring flocks for novel IBV field isolates should continue given the identification of Israel/720/99, and perhaps others in the future. Strains selected for vaccination of commercial flocks should induce cross- protection against unrelated genotypes. Using diverse genotypes for vaccination may result in immunity against unrelated field strains.
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Butler, Nadia, and Soha Karam. Evidence Review: COVID-19 Vaccine Acceptance by Key Influencers in the MENA Region - Teachers and Healthworkers. Institute of Development Studies (IDS), November 2021. http://dx.doi.org/10.19088/sshap.2021.039.

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As COVID-19 vaccines have been deployed and scaled, concerns about vaccine acceptance have emerged. Effective management of the virus requires that communities everywhere buy into the public health measures designed to protect them, including vaccines. Low acceptance presents a serious challenge for achieving sufficient coverage to reduce circulation of the virus and the risk of new variants emerging. Surveys conducted early in the pandemic showed that the Middle East region had one of the lowest COVID-19 vaccine acceptance rates globally. The low acceptance is driven by specific factors in the region and its different countries and populations; these factors need to be taken into account when formulating policy, programmes and interventions. This review synthesises evidence on vaccine acceptance among two key groups in the Middle East and North Africa (MENA) region: teachers and health workers. It draws from academic studies most of which were cross-sectional studies, largely conducted between February 2020 and June 2021, and grey literature reports, including social listening reports. This review is intended to inform strategies for risk communications and community engagement (RCCE) relating to COVID-19 vaccine uptake, with the aim of boosting confidence in and acceptance of the vaccines among these groups across the region. It is part of the Social Science in Humanitarian Action Platform (SSHAP) series on social science considerations relating to COVID-19 vaccines and was developed for SSHAP by Anthrologica (Nadia Butler and Soha Karam) at the request of the UNICEF MENA Regional Office. It was reviewed by Rose Aynsley (WHO) Amaya Gillespie (UNICEF) and Olivia Tulloch (Anthrologica). The evidence review is the responsibility of SSHAP.
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Haider, Huma. Malaria, HIV and TB in Nigeria: Epidemiology and Disease Control Challenges. Institute of Development Studies (IDS), December 2021. http://dx.doi.org/10.19088/k4d.2022.040.

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Nigeria has the world’s highest number of people affected by malaria and the world’s second largest human immunodeficiency virus (HIV)/AIDS burden. There is a high occurrence of co-infection of malaria in HIV patients (Gumel et al., 2021). Nigeria is also ranked as one of the thirty high tuberculosis (TB) and TB-HIV co-infection burden countries in the world (Odume et al., 2020, 8). Co-infection can make each disease more severe and potentially more infectious (Gumel et al., 2021; Jemikalajah et al., 2021; Chukwuocha et al., 2019). This rapid literature review highlights key aspects of the epidemiology of malaria, HIV and TB in Nigeria, in addition to challenges in controlling the three diseases, in terms of prevention, detection and treatment. This is part of a series of reports looking into Epidemiology of Malaria, human immune deficiency virus (HIV) and tuberculosis (TB) across a set of African Nations.
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