Academic literature on the topic 'Blood-borne viruses'

There is increasing concern about hepatitis C virus (HCV) and potential HIV transmission among ethnic Vietnamese injecting drug users (IDUs) in Australia. To date ethnic and cultural differences in vulnerability to blood-borne viruses (BBV) have received little attention and few studies have attempted to explore the role of cultural beliefs and values in influencing injection risk behaviour. This study aimed to systematically explore the cultural beliefs and behavioural practices that appear to place ethnic Vietnamese IDUs at increased risk of BBV infection, identify barriers to this group accessing health and preventive programs, and document antibody HIV and HCV prevalence and associated risk behaviours. The first component of the research consisted of an ethnographic study designed to explore underlying explanatory models of health and illness employed by Vietnamese IDUs and identify cultural influences on risk behaviours and vulnerability to BBVs. These data were subsequently used to inform the development of the instrument used in the second component ??? a cross-sectional survey and collection of capillary blood samples designed to assess risk behaviours and antibody HIV and antibody HCV prevalence. Analysis of data from both components indicates that cultural beliefs and practices influence risk-taking and health-seeking behaviours and suggests pathways through which this influence occurs. Relevant cultural characteristics include those pertaining to spiritual and religious beliefs, the role of the family and traditional Vietnamese family values, cultural scripts of self-control and stoicism, the importance of ???face??? and non-confrontational relationships, trust and obligation, and a reluctance to discuss problems with outsiders. Vulnerability to BBVs is influenced by these cultural characteristics, together with Vietnamese IDUs??? perceptions of risk, knowledge about HIV and HCV, and situational and environmental factors. Main factors contributing to the under-utilisation of health services include the use of self-managed care practices, ambivalence surrounding Western medicine, long waiting times, concerns in relation to confidentiality, stigmatisation of drug use, and limited knowledge of BBVs. The data indicate a need for interventions based on understanding of culturally specific meanings and contexts of health, illness and risk in order to better meet the needs of this vulnerable group.

Injecting drug use is a key risk factor, and injecting drug users (lDUs) are a core group for several blood-borne viruses (BBV) including hepatitis B (HBV) and hepatitis C (HCV). In 2003 the Unlinked Anonymous Prevalence Monitoring Programme reported that 62% of surveyed IDUs in England and Wales were found to ever having been imprisoned. Thus prison may provide a good opportunity to administer health interventions against BBVs to this hard to reach population. The aim of the thesis is to examine a number of alternative intervention measures that target IDUs in a prison setting against BBVs. Methods to inform as to the characteristics of the IOU population and its risk of infection from BBVs are also proposed. A method to determine the age specific rates at which individuals enter and leave the IOU population is presented. An age-specific dynamic model is developed that describes the flow of IDUs and non-IDUs through prison. This model is used to assess the potential impact of the HBV vaccination programme in England and Wales on the vaccination coverage of the IOU population showing that over 70% of IDUs may be captured with vaccination. Taking data that describes the prevalence of HBV and HCV in current IDUs in England and Wales, the injecting career length specific forces of infection for HBV and HCV in the IOU popUlation in England and Wales are estimated, these provide further evidence that new initiates to injecting may be at increased risk of infection compared to more experienced IDUs. Parameterised models are used to assess the impact that prison vaccination will have on HBV transmission within the IDU population with results showing that prison vaccination may result in a 75% reduction in acute infections in IDUs within 12 years from the start of the programme. Finally the cost effectiveness of HCV casefinding on prison reception is investigated showing the importance of encouraging current or former IDUs to accept ELISA testing on prison reception. The results provide further evidence that prison may be a good location in which to implement intervention measures against BBVs. The results also provide an increased understanding of the characteristics of IOU population in England and Wales and in particular its risk of infection from HBV and HCV.

Solid organ transplantation is a rare health intervention that saves lives, improves quality of life and, where there is an alternative such as dialysis, is cost-effective. However, organ transplantation is a complex intervention that is limited by the number of organ donors, and requires life-long immunosuppression of the recipient. Infections are a common complication of organ transplantation, and a major cause of death for transplant recipients. Donor-derived infections, while rare, are of particular concern for transplant clinicians, as a potentially avoidable consequence of transplantation. Donation practice must balance the risks of infection transmission with the risks of overly restrictive donation policies that could limit this life-saving intervention. Post-transplant, clinicians must remain vigilant for new recipient infections, whether donor-derived, reactivating or arising anew. In this thesis, I generate novel data regarding aspects of infections affecting solid organ donation and transplantation where current practice can be improved, focusing in particular on blood-borne viruses and preventable post-transplant infections. Theme 1: Assessment of potential organ donors for blood-borne virus transmission risk All potential solid organ donors are rigorously screened for their suitability to donate. One reason potential donors may be declined is where there is perceived to be an increased risk of transmission of infectious diseases, including blood-borne viruses (BBV) such as hepatitis B (HBV), hepatitis C (HCV) and human immunodeficiency virus (HIV). Unexpected BBV transmissions have indeed led to devastating recipient outcomes. However, testing and treatment for these conditions have evolved substantially in recent years and decades. Nucleic acid testing (NAT) is now both rapidly available and highly sensitive for infection. Implementation of NAT reduces serological window periods to smaller eclipse periods. Meanwhile, HCV has become curable in the vast majority of cases, HBV can be prevented with vaccination, or effectively suppressed, and even HIV now has effective suppressive treatments. Given these developments, a reassessment of suitability of potential organ donors with BBV, or risk factors for their acquisition, is warranted. The first aim of this thesis was to understand whether transplant clinicians can correctly interpret hepatitis serology and then consistently judge potential donor transmission risk and donation suitability. This is explored in Chapter 2 through an anonymous, self-completed, cross-sectional survey distributed electronically to Australian and New Zealand clinicians involved in kidney transplantation (2014-2015). We compared respondents’ interpretation of clinical scenarios with paired donor and recipient hepatitis B and C serology to recommendations in clinical practice guidelines. We then used logistic regression modelling to investigate characteristics associated with decisions on transplant suitability in scenarios with poor (<50%) guideline concordance. The 110 survey respondents in our sample had demographic characteristics representative of the target workforce. While donor and recipient hepatitis statuses were largely well understood, transplant suitability responses varied among respondents. For an HBV surface antigen (HBsAg) positive donor and vaccinated recipient, 44% of respondents suggested the donor was unsuitable for transplant (guideline concordant) but 35% suggested the donor was suitable with prophylaxis (guideline divergent). In four scenarios with transplant suitability guideline concordance of <50%, acute transplant care involvement predicted guideline concordant responses (OR [odds ratio] 1.69, p=0.04). Guideline concordant responses were chosen less by hepatologists, intensive care doctors (OR 0.23, 0.35 respectively, p=0.01), and New Zealanders (guideline concordant responses OR 0.17, p<0.01; alternative responses OR 4.31, p<0.01). Hence, we conclude that despite broadly consistent interpretations of hepatitis serology by respondents, resulting transplant suitability decisions vary, and often diverge from guidelines. Having established variability between clinicians, this thesis next aimed to describe current practice regarding potential donors with increased risk for BBV transmission in Chapter 3. Specifically, we aimed to describe the size and characteristics of this group, whether they proceeded to donate, and reasons not donating. To do this, we conducted a cohort study of all potential organ donors referred in New South Wales, Australia between 2010 and 2018. Baseline risk potential donors were compared to potential donors with increased BBV transmission risk, due to a personal history of HIV, HCV or HBV and/or behavioural risk factors. We found 624/5749 potential donors (10.9%) perceived to have increased BBV transmission risk. This included 298/5749 (5.2%) with HCV (including HBV co-infections) and 239/5749 (4.2%) with increased risk behaviours (no known BBV). Potential donors with HCV and those with increased risk behaviours were younger and had fewer comorbidities than baseline risk potential donors (p<0.001). Many potential donors (82 with HCV, 38 with risk behaviours) were declined for donation purely due to perceived BBV transmission risk. Most were excluded prior to BBV testing. When potential donors with HCV did donate, they donated fewer organs than baseline risk donors (median 1 versus 3, p<0.01), especially kidneys (OR 0.08, p<0.001) and lungs (OR 0.11, p=0.006). In summary, many potential donors were not accepted due to perceived increased BBV transmission risk, without viral testing, and despite otherwise favourable characteristics. This suggests the potential for transplantation rates to be substantially increased if more potential donors with HCV and/or increased risk behaviours were accepted. Taken together, the findings of variable donor suitability decision-making, and the rejection of otherwise high-quality potential donors without viral testing, suggest there may have been missed opportunities to donate from some potential donors with positive serology or increased risk behaviours. Supporting clinicians to identify such previously rejected potential donors with an acceptable risk profile, and using these organs for transplantation, may have the potential to significantly increase donation rates. Theme 2: Estimating the actual risks of BBV transmission To support change in clinical practice, estimates of the risks posed by increased risk donors are helpful. Blood-borne virus rates vary internationally, and no data from the Australian context was available. We synthesised existing literature to produce Australian estimates of the actual risk posed by potential donors with increased risk behaviours for BBV only (Chapter 4). We conducted a systematic review and meta-analysis of cohorts reporting incidence and prevalence of HIV, HCV and HBV among increased risk groups in Australia. The residual risks of window period infections were estimated in the setting of negative serology and NAT. Residual risk of HIV was found to be highest among men who have sex with men at 4.8 per 10,000 persons testing negative with serology (95% CI: 2.7-6.9), and 1.5 per 10,000 persons with additional negative NAT (95% CI: 0.9-2.2). Residual risk of HCV was highest among injecting drug users (IDU) with a residual risk of 289 per 10,000 persons (95% CI: 191-385) with negative serology, and 20.9 per 10,000 persons (95% CI: 13.8-28.0) with additional negative NAT. Residual risk for HBV was highest in IDU with 98.6 window period infections per 10,000 with negative serology (95% CI: 36.4-212.7) and 49.4/10,000 with additional negative NAT (95% CI: 18.2-106.9). We concluded that the absolute risks of window period infection are low among Australian groups with increased risk but negative viral testing. These findings inform shared decision-making by clinicians and recipients and have the potential to increase organ donation rates from increased risk donors where risks are considered tolerable. To understand the magnitude of transmission risks from donors with positive hepatitis serology, we next examined a cohort of linked donors and recipients (Chapter 5). The aims of this work included describing the rates of transmission and non-transmission of BBV from donors with BBV to recipients, and identifying any previously unrecognized transmissions from donors perceived to pose a baseline transmission risk. To do this, we linked transplant registries with administrative health data for all solid organ donor-recipient pairs in New South Wales, Australia, 2000-2015. All new recipient notifications of HBV, HCV or HIV after transplant were identified. Proven/probable donor-transmissions within 12 months of transplant were classified according to a published US algorithm. Of 2,120 organ donors, there were 72 with a viral infection (9/72 active, 63/72 past). These 72 donors donated to 173 recipients, of whom 24/173 already had the same infection as their donor, and 149/173 did not and so were at risk of donor-transmission. Among those at risk: 3/149 recipients had proven/probable viral transmissions (1 HCV, 2 HBV); none were unrecognised by donation services. There were no deaths from transmissions. There were no donor-transmissions from donors without known BBV. Our findings confirm the safety of organ donation in an Australian cohort, with no unrecognised viral transmissions and most donors with viral infections not transmitting the virus. The results support targeted increases in donation from donors with viral infections. Data-linkage can enhance current biovigilance systems. The local evidence of transmission risks generated in Chapters 4 and 5 provide much-needed data to tackle the evidence and practice gap established in Chapters 2 and 3. This allows the implementation of changes in clinical donation and transplantation practice which could safely increase donation rates. Theme 3: Recipient infections after transplantation Another finding from the research in Chapter 5 was the identification of a substantial number of new BBV infections that were unrelated to donor transmission risk. Beyond the 3 identified proven/probable transmissions reported above, an additional 68 recipients had new virus notifications, of whom 2/68 died due to HBV infection. The infections in these 68 recipients may have been undetected late transmission, reactivating HBV, or de novo infections. Substantial preventative measures are available for these conditions including vaccination and avoiding risk-exposures. Stimulated by this concern about preventable non-transmitted infection, Chapter 6 of this thesis aims to understand the burden of notifiable infections post-transplant, which often have known preventive strategies. To do this, we conducted a cohort study of all solid organ recipients transplanted in New South Wales, Australia, 2000-2015. We used data-linkage to connect transplant registers to hospital admissions, notifiable diseases database, and the death register. We then calculated standardised incidence ratios (SIR) relative to general population notification rates, accounting for age, sex, and calendar year, and identified infection-related hospitalisations and deaths. Among 4,858 solid organ recipients followed for 39,183 person-years, there were 792 notifications. Influenza was the most common infection (532 cases, incidence 1358/100,000 person-years, 95%CI:1247-1478), with the highest prevalence within 3 months post-transplant. The second most common was salmonellosis (46 cases, incidence 117/100,000 person-years, 95%CI:87-156), followed by pertussis (38 cases, incidence 97/100,000 person-years, 95%CI:71-133). Influenza and invasive pneumococcal disease (IPD) in transplant recipients showed significant excess cases compared with the general population (influenza SIR 8.5, 95%CI:7.8-9.2, IPD SIR 9.8, 95%CI:6.9-13.9), with high hospitalisation rates (47% influenza cases, 68% IPD cases) and some mortality (four influenza and one IPD deaths). By 10 years post-transplant, cumulative incidence of any vaccine-preventable disease was similar for most transplanted organs at 12%, except for lung recipients, where it was nearly 30%. Gastrointestinal diseases, tuberculosis and legionellosis had excess cases among transplant recipients, although there were few sexually transmitted infections and vector-borne diseases. Improved vaccination programs, health education, and pre-transplant donor and recipient screening have the potential to reduce preventable infections among transplant recipients. Conclusion: This thesis explores some ways in which infectious diseases impact organ donation and transplantation, and identifies areas where clinical practice could be improved. Transplant clinicians need more support to interpret hepatitis transmission risk as they have variable interpretations of suitability. Many potential donors have increased risks for BBV transmission, with otherwise favourable characteristics, and did not donate. Actual transmission risks from both Australian donors with BBV and potential donors with increased risk behaviours are, in absolute terms, low. A reconsideration of risk profiles for potential donors with increased BBV transmission risk could materially increase organ donation rates in Australia. In addition, organ transplant recipients have significant post-transplant infections, including both BBV and other notifiable infections such as vaccine-preventable and gastrointestinal infections. Important infections post-transplant could be prevented by improved vaccination uptake and optimised strategies, donor and recipient screening for latent infection, and donor recipient education.

Thesis (MPH) -- University of Limpopo, 2011.
Background: Health care workers (HCWs) are prone to occupational exposures to blood-borne viruses (BBVs), which include hepatitis B virus (HBV), hepatitis C virus (HCV), and human immunodeficiency virus (HIV). Post exposure prophylaxis (PEP) is available for both HBV and HIV, and if administered correctly can reduce the risk of HBV and HIV transmission by 80%. This study investigated the knowledge and practices of HCWs regarding PEP for BBVs at Medunsa Oral Health Care Centre (MOHC). Methods: This was a cross sectional study conducted among 166 HCWs at the MOHC using a self-administered, anonymous questionnaire on knowledge and practices of HCWs regarding PEP for BBVs. Binary logistic regression method was used to determine factors associated with reporting an occupational exposure and uptake of PEP. Results: The response rate was 67%. The mean age was 27yrs (SO =7.67yrs), and 68.7% of . respondents were female. The overall knowledge regarding PEP among the HCWs was inadequate as 46.9% had poor knowledge. The majority (77.7% [128/166]) of HCWs experienced occupational exposures and amongst them 39.0% (50/128) experienced it twice or more. Almost two-thirds (60.9%) of HCWs experienced an occupational exposure while performing scaling and polishing. Only 28.9% (37/128) of those who were potentially exposed to a BBV reported the incident to the authorities. Out of those who reported, 37% (14/37) took PEP for HIV, and 32.4% (12/37) took PEP for HBV. Among those taking HIV PEP, 21.4% (3/14) indicated that they completed the course. HCWs who haq five or more years of experience j were less likely (OR=0.138, p=0.043) to report compared to those who had less than five years of experience. Conclusion: Overall, participants' knowledge regarding PEP as well as reporting of an exposure was inadequate. The majority of HCWs experienced an occupational exposure while performing scaling and polishing.

Introduction International guidelines endorse the screening of patients for human immunodeficiency virus (HIV), hepatitis B virus (HBV), hepatitis C virus (HCV) and Chlamydia trachomatis before assisted reproductive techniques (ART). At present no such guidelines exists in South Africa. At the Reproductive and Endocrine Unit (referred to as “the Unit”) of Steve Biko Academic Hospital, all patients with unknown HIV status are counselled and a blood sample is collected during the initial visit for automated laboratory based HIV screening. These HIV results are not available before semen samples are processed. Furthermore, patients are not screened for HBV, HCV and Chlamydia trachomatis. Couples attending the Unit are of a low to middle socio-economic status and experience financial constraints. Moreover, automated laboratory based assays are expensive to perform. Rapid testing is a cost effective and practical method from screening patients, with a 20–30 minute result turnover time. Until screening at the Unit is improved, the possible identification of semen characteristics that could indicate HIV infection would be a useful tool. Materials and Methods The following rapid point-of-care assays were evaluated: Determine® HIV-1/2 combo test (n=100), Determine® HBsAg test (n=100), DIAQUICK HCV kit (n=74), and the DIAQUICK Chlamydia trachomatis kit (n=30). For profiling, parameters from a basic semen analysis of HIV-positive males (n=60) were compared with HIV-negative males (n=60). Information pertaining to CD4 count, antiretroviral treatment and plasma viral load of HIV-positive males were analysed. Results From all patients included in the study, 8% tested positive for HIV. The risk of a female being HIV-positive was 3.73 times higher than for males. In the pilot study to explore rapid testing for HBV and HCV, 1% and 1.4% of patients tested positive respectively. When testing for Chlamydia trachomatis 31.3% of females, but no males tested positive. Comparing semen profiles, no significant differences were found between samples from HIV positive and negative males or between HIV positive males categorised by CD4 cell count (p>0.05). For the HIV-positive group with a detectable plasma HIV viral load (>40 copies/ml), a significant difference was observed in the semen viscosity (p=0.0460). Significant differences were noted in the sperm motility (immotile sperm p=0.0456, progressive sperm p=0.0192) of patients receiving antiretroviral (ARV) therapy. Discussion and Conclusion The use of rapid testing is an acceptable and feasible option for improving current screening protocols at the Unit. The absence of definite alterations in the semen characteristics of HIV-positive men further motivates the need for a simpler, point-of-care screening protocol. The prevalence of HBV was lower than that reported in the general population of South Africa and further investigation is needed. Although the sample size was small, HCV prevalence was similar to that of the general population. One third of females tested positive for Chlamydia trachomatis. The methodology used was possibly not appropriate for males. This study highlighted the need for guidelines that address the specialised needs of ART clinics in resource-limited and developing countries with a high HIV prevalence.
Dissertation (MSc)--University of Pretoria, 2013.
gm2014
Obstetrics and Gynaecology
unrestricted

Magister Curationis - MCur
Background: Health care workers who sustain needle stick injuries are at risk of contracting blood-borne pathogens, e.g. Human Immunodeficiency Virus,Hepatitis B virus or Hepatitis C virus. Needle stick injuries are viewed as occupational hazards that can lead to health care workers developing acute or chronic diseases, which may lead to disability or death. Due to these healthrelated risks, health care workers are encouraged to adhere to universal precautions and standard operating procedures. In South Africa, the Occupational Health and Safety Act promulgated in 1993 required institutions draw up protocols in line with the regulations of the Act. However, if the health care workers do not comply with the protocols they may not be compensated for contracting a disease, e.g. Human Immunodeficiency Virus infection, following needle stick injuries. Aim: The aim of the study was to explore the health care workers’ perceptions of the needle stick injury protocol at a level 2 hospital in Cape Town. Research design: A qualitative approach was used to make sense of health care workers’ compliance to the protocols when sustaining a needle stick injury. An exploratory descriptive, contextual design was used to carry out an in-depth investigation of the phenomenon. Sample: The study was done at Mowbray Maternity Hospital, a level 2 obstetric hospital in Cape Town. The researcher made use of convenience, purposive sampling. Semi-structured interviews were used to collect the research data. Data collection: During the data collection phase, ethical considerations towards participants were ensured to include, among others, anonymity, autonomy and confidentiality of information. Data analysis: It included the following steps: reading and rereading,coding, displaying, reducing and interpreting the data. Findings: Some health care workers do not view sustaining a needle stick injury as risky enough to report the injury or even go for follow-up testing. This risky behaviour can have detrimental effects on their health. There is also a lack of knowledge about the institutional needle stick injury protocol. Recommendations: It is recommended to have educational and training sessions for all health care workers and new employees to familiarise them with the needle stick injury protocol and policies of the institution; to provide adequate management support 7 following work related injuries and to make health care workers aware of the consequences of non-compliance to institutional protocol.

The rate of sexually transmissible infections and other blood-borne viruses is high in South Australia. Young people are prone to contracting these diseases who rely on school programs for their health-related behaviours. Health-related behaviours, specifically knowledge and attitudes, can successfully disseminate from teachers to students. Hence, the present study explored the knowledge and attitudes of pre-service teachers in South Australia towards these diseases besides evoking perspectives towards disease-related issues, the role of an effective education thereof, and teacher education in addressing sexual health. The samples (N = 320) comprised of pre-service teachers enrolled in teacher education courses at higher educational institutions in the State. Data collection from the samples took the form of a cross-sectional survey, both at the pilot and the main stages of study. The pilot study was essential to establishing the validity and reliability aspects of the knowledge and attitude scales of the developed questionnaire, which, however, was also measured at the main stage of analysis. A Rasch item analysis using the Quest Version 2.1 software established evidence of a construct validity and an acceptable reliability of both the scales at either stages of study. Subsequent data analysis pertaining to the knowledge and attitudes largely depended on the Rasch estimates being non-parametric, and therefore, the application of non-parametric statistics using the SPSS Version 18.0 software. The open-ended perspectives with 272 valid responses, however, underwent a qualitative thematic analysis. The quantitative analysis revealed a poor level of knowledge (mean score of 18.57 out of a possible 45) and a favourable attitude (mean score of 44.45 out of a possible 51) of South Australian pre-service teachers towards the diseases, with a low to moderate positive relationship between the knowledge and attitude attributes (rs = .196, p < 0.01) [s subscript]. School, peers, and mass media campaigns constituted the major sources of information related to the diseases. There were no significant differences of either the knowledge or the attitude scores across the demographic variables gender, highest educational level, subject stream, and undertaking the related curriculum. However, attitude scores varied across age, with knowledge revealing no significant difference as earlier. The qualitative analysis revealed that the majority of pre-service teachers perceived an information gap and an attitude and behaviour of individuals as primarily responsible for a high disease rate in the State and young people contracting these, respectively. The majority perceived that the related curriculum does not address STI-related issues and that teachers are primarily responsible for the lack of a comprehensive sex education in the State. The majority, however, was largely supportive towards the call for a compulsory sex education. Further, reflecting that they themselves lack adequate knowledge on these diseases, pre-service teachers suggested the introduction of sexual health as a core topic in teacher education. The findings have implications for educators, policy makers, key stakeholders in the field of sexual health education, and the school and the community to raise awareness of the many areas that adolescents and young adults experience problems in, and particularly related to sexual health.
Thesis (Ph.D.) -- University of Adelaide, School of Education, 2013

From February 2013 to November 2014 I undertook a field placement at the Kirby Institute for Infection and Immunity in Society (the Kirby Institute), as a part of a Master of Philosophy in Applied Epidemiology (MAE). This bound volume is the product of projects undertaken while at the Kirby Institute in the Justice Health Research Program and the Public Health Interventions Research Group. Within are six chapters which demonstrate work undertaken, lessons learnt, knowledge gained and MAE requirements met. Due to my placement predominantly in the justice health research program, three out of four major projects have a focus on blood borne viruses and associated risk factors among offender populations. I evaluated the national prison entrant’s blood borne virus and risk behaviour survey (NPEBBVS), the only multi-jurisdictional prison BBV monitoring mechanism nationally. As a data analysis project I explored hepatitis B core antibody and hepatitis C antibody prevalence and associated risk factors among Indigenous and non-Indigenous prison entrants from the NPEBBVS. Findings from this chapter were presented at a number of conferences and events. As an acute public health problem, I had the opportunity to investigate hepatitis C (HCV) incidence cases in a prison facility. We developed a case series study using mixed methods to collect data on the unusual cluster of HCV cases. I conducted both quantitative and qualitative interviews with participating inmates to gather prisoner’s perspective of HCV incidence, understanding routes of transmission in the prison setting and possible strategies in decreasing exposure and risk. From the start of 2013 I was involved in the ‘vaccine impact in the Indigenous population’ (VIP- I) study with a large group of investigators. The aim of VIP-I was to evaluate the effectiveness of the HPV vaccine among Indigenous women in Australia. My role in the study was as a field coordinator, chapter 5 demonstrates my involvement from the development stage onwards. This chapter is largely methodological, only preliminary results are presented as recruitment is still ongoing. Teaching experience during the MAE included; lessons from the field and a group teaching session with MAE peers. I worked individually on a project management module for the lesson from the field exercise, my fellow MAE cohort completed this module which touched on interdisciplinary collaboration in research. The group teaching experience was created and conducted with two fellow MAE scholars, we built a framework to distinguish real or artificial rate change when interpreting time series data. The projects within this thesis contribute to the Kirby Institutes area of work with marginalised at risk populations. I have been fortunate to be a part of a number of projects that have potential to impact public health policy and programs for both Indigenous and offender populations.

The South Australian Communicable Disease Control Branch at SA Health is responsible for public health and protection of South Australians through the surveillance and detection of communicable diseases. I was placed within the Branch between 2014 and 2015 as a Masters of Philosophy in Applied Epidemiology (MAE) scholar. In this thesis I present work undertaken during my placement to fulfil the requirements of the MAE. Three of my projects all involved the investigation of Salmonella Typhimurium phage type 9 (STM 9) notifications in South Australia. Notifications of STM 9 have been increasing in South Australia over the past ten years and in 2014 represent a third of all Salmonella notifications in the state. I conducted a data analysis of STM 9 notifications in South Australia between 2005 and 2014. A descriptive and analytical review of notifications was conducted to define trends and changes in the surveillance data and to provide insight into the increase in case numbers. The analysis compared sporadic and outbreak cases and detailed the descriptive characteristics of different multiple-locus variable-number tandem-repeat analysis patterns reported for this phage type. The analysis identified higher notification rates in people living in areas of higher socio-economic advantage and a particular increase in case numbers since 2012. It also identified a large proportion of outbreaks associated with eggs. I conducted a case control study to identify risk factors for sporadic STM 9 notifications in South Australia. This project involved interviewing sporadic STM 9 cases who were frequency matched with controls by age category. The questionnaire explored food, environmental and behavioural exposures. The interim analysis included in this thesis includes 332 participants (40 participants short of the required sample size) and identifies defrosting meat by submerging in water as a potential risk factor and consuming caged eggs as a potential protective behaviour. I investigated an outbreak of STM 9 in a group of school children staying at a campsite in New South Wales while visiting Canberra on a school excursion. The investigation was able to alert other jurisdictions to the potential problem, which resulted in the identification of another affected school group from New South Wales. The cohort study with the South Australian school group was unable to identify a specific source of the outbreak. The environmental investigation conducted at the campsite did not identify any problems and food and environmental samples obtained were all negative for Salmonella. For my remaining project I undertook an evaluation of the South Australian infectious syphilis surveillance system. The evaluation used the Centers for Disease Control and Prevention guidelines to assess ten surveillance system attributes. The impact of three proposed probable case definitions were also assessed. I was able to identify that the system, although highly sensitive, had variable data quality and inconsistencies due to the lack of a systematically applied case definition. Improvements in feedback to external stakeholders were recommended. The probable case definition requiring single high rapid plasma regain cut off greater than or equal to 16, and not requiring a case to have risk factors, had the highest sensitivity.

Blood- borne viruses (BBVs) are viral infections transmitted by blood or body fluid. In practice, any viral infection that achieves a high viral load in blood or body fluid can be transmitted through exposure to infected biological materials. In western countries, the most significant BBVs are human immunodeficiency viruses (HIV1 and HIV2), hepatitis B virus (HBV) and hepatitis C virus (HCV). Other viruses that can be transmitted by blood and body fluid include human T cell lymphotropic viruses (HTLV1 and HTLV2), cytomegalovirus, West Nile virus and viruses responsible for viral haemorrhagic fever such as Ebola virus, Lassa virus, and Crimean-Congo haemorrhagic fever virus. BBVs are transmitted via exposure to blood and body fluid. Some examples of routes of transmission include: ● Sharing needles in people who inject drugs (PWID); ● Medical re-use of contaminated instruments (common in resource poor settings); ● Sharps injuries in healthcare setting, including in laboratories (less commonly through mucosal exposure); ● Transfusion of blood contaminated with BBVs (failure to screen blood donors); ● Transplantation of organs from BBV-infected donors; ● Sexual exposure to BBV-infected body fluid; and ● Exposure to maternal BBV infection: intrauterine, perinatally, or postnatally. If exposure to a BBV is via a needle stick injury in a healthcare setting, immediate first aid needs to be carried out by gently encouraging bleeding and washing the exposed area with soap and water. Prompt reporting of the incident is required so that an assessment can be done as soon as possible to determine if post-exposure prophylaxis (PEP) is required. The decision may be aided by urgent assessment of source patient infection status. The British Medical Association has issued guidance for testing adults who lack the capacity to consent. In the case of a sexual exposure to a BBV, immediate consultation to a genito-urinary medicine (GUM) clinic is warranted. The risk of transmission of BBVs associated with exposure depends on the nature of the exposure and the body fluid involved. The following factors are important in needle stick injuries: ● Deep percutaneous injury. ● Freshly used sharps. ● Visible blood on sharps.