Risk Of Seroconversion Research Articles

Assessment of the long-term effect of vaccination on transmission of infectious bovine rhinotracheitis virus in cattle herds hyperimmunized with glycoprotein E–deleted marker vaccine

To assess long-term effects and risk factors for the efficacy of hyperimmunization protocols against infectious bovine rhinotracheitis (IBR) during a longitudinal field study of dairy and dairy-beef mixed farms. Approximately 7,700 cows from 72 farms. Farms were assigned to 3 treatment groups (hyperimmunization groups [HIGs] 1 and 2, which were hyperimmunized with glycoprotein E [gE]-deleted marker vaccines, and a nonintervention group [NIG]). Cattle in HIG 1 were initially vaccinated with an attenuated vaccine, whereas cattle in HIG 2 were initially vaccinated with an inactivated-virus vaccine. Cattle in both HIGs received booster inoculations with inactivated-virus vaccines at 6-month intervals. The risk for gE seroconversion was compared among experimental groups via a shared frailty model with a piecewise constant baseline risk to correct for seasonal and secular effects. Risk for gE seroconversion significantly decreased over time for the HIGs, compared with the NIG. Seasonal changes in the risk of gE seroconversion were detected, with a higher risk during winter periods, compared with grazing periods. No significant difference was detected between HIGs 1 and 2. The only significant risk factor was the number of buildings for cattle on a farm; the higher the number of buildings, the lower the risk for gE seroconversion. Prevalence of IBR decreased over time in both HIGs but remained constant or increased in the NIG. Hyperimmunization via repeated administration of attenuated and inactivated-virus gE-deleted marker vaccines as well as inactivated-virus vaccines may provide a method for control of IBR.

Sexual Partner’s Age as a Risk Factor for HIV Seroconversion in a Cohort of HIV-Negative Homosexual Men in Sydney

Increasing partner age may be an important risk factor for HIV infection in homosexual men. About 20% of 1,427 participants in the Health in Men study in Sydney, Australia, reported that half or more of their partners were much older. Having more partners who were much older was associated with an increased risk of HIV seroconversion (p trend=0.002), and this remained significant after adjustment for participants' age, number of regular and casual partners, and sexual risk behaviour (p trend=0.027). Men who reported much older partners were at increased risk of HIV infection, independent of unprotected anal intercourse with sero-nonconcordant partners.

EBV primary infection in childhood and its relation to B-cell lymphoma development: A mini-review from a developing region

In most underdeveloped countries, the initial contact with Epstein Barr virus (EBV) usually happens in the first decade of life and results in an asymptomatic infection, whereas in developed areas, primary infection in adolescence or adulthood is accompanied by infectious mononucleosis in 50% cases. Although it is generally a harmless passenger, in some individuals, it is associated with B-cell lymphoma. In Argentina, EBV primary infection shows the classical pattern observed in developing populations, given that nearly 70% of patients are seropositive by the age of 2 years. However, EBV association with pediatric Hodgkin and Burkitt lymphoma resembles that observed in developed regions. Concerning diffuse large B-cell lymphoma, our series demonstrated higher EBV association than other adult ones from either developed or underdeveloped countries. Interestingly, the early EBV primary infection observed, characteristic of an underdeveloped population, together with the statistically significant EBV association with patients ≤ 10 years old demonstrated in all types of lymphoma studied, suggest a relationship between low age of EBV seroconversion and B-cell lymphoma development risk.

Year-to-year volatility in medical admissions

British Journal of Healthcare ManagementVol. 18, No. 8 Money MattersYear-to-year volatility in medical admissionsRod JonesRod JonesSearch for more papers by this authorRod JonesPublished Online:16 Aug 2013https://doi.org/10.12968/bjhc.2012.18.8.448AboutSectionsView articleView Full TextPDF/EPUB ToolsAdd to favoritesDownload CitationsTrack CitationsPermissions ShareShare onFacebookTwitterLinked InEmail View article References Hyde T Schmid S Cannon M (2010) Cytomegalovirus seroconversion rates and risk factors: implications for congenital CMV. Rev Med Virol 20(5): 311–26 Crossref, Google ScholarJones R (2012a) Could cytomegalovirus be causing widespread outbreaks of chronic poor health? In: Shoja MM Agutta PS Tubbs Set al., eds. Hypotheses in Clinical Medicine. Nova Science Publishers Inc, New York, NY Google ScholarJones R (2012b) Cancer care and volatility in commissioning. BJHCM 18(6): 315–24 Google ScholarJones R (2012c) End of life care and volatility in costs. BJHCM 18(8): 374–81 Google ScholarMaes M Berk M Goehler Let al. (2012) Depression and sickness behaviour are Janus-faced responses to shared inflammatory pathways. BMC Medicine 10: 66 Crossref, Google Scholar FiguresReferencesRelatedDetails 1 August 2012Volume 18Issue 8ISSN (print): 1358-0574ISSN (online): 1759-7382 Metrics History Published online 16 August 2013 Published in print 1 August 2012 Information© MA Healthcare LimitedPDF download

Occupational hepatitis C seroconversions in a Brazilian hospital

There are six known cases of occupational human immunodeficiency virus (HIV) seroconversion in Brazil. However, there are neither published cases of occupational hepatitis C virus (HCV) seroconversion nor systematic studies of blood and body fluid exposures (BBFE) that could estimate the risk of HCV or HIV occupational seroconversion in Brazil. To describe the outcomes of BBFEs in a Brazilian hospital over 12 years and 2 months. Statistical analysis of a computerized database of exposure events recorded on printed forms. Incidence rates (IR) were calculated as the number of BBFE per 100 full-time equivalent worker-years. There were 1457 BBFE, 87% being percutaneous and 561 (38%) recurring in health care workers (HCWs) who reported having previous exposures. The highest IRs occurred in laboratory technicians (9.7), medical students (9.5), cleaning staff (9.5) and nursing aids (9.2). The IR in temporary employees was 13.0. Two HCWs, a nursing aid and a surgeon, seroconverted to hepatitis C after HCV exposures involving 13 G catheter needles. The risk of acquiring a HCV infection was 2 in 38 percutaneous HCV exposures, i.e. 5% (95% CI: 0.89-16.3). There were no seroconversions to HIV despite 80 percutaneous HIV exposures. HCV has a higher potential for occupational transmission than HIV. Measures to reduce the risks of BBFE and occupational transmission of blood-borne viral infections should be improved in Brazil.

Population-level impact of hormonal contraception on incidence of HIV infection and pregnancy in women in Durban, South Africa

To estimate the potential impact of using hormonal contraceptives on rates of infection with human immunodeficiency virus type 1 (HIV-1) and pregnancy by theoretically removing the use of hormonal contraceptives from a study population. A prospective cohort study included 3704 HIV-negative women who were enrolled in two biomedical trials that tested two vaginal microbicides (PRO 2000 and Carraguard®) for the prevention of HIV-1 in Durban, South Africa, in 2004-2009. Cox proportional hazards regression models along with partial population attributable risks (PARs) and their 95% confidence intervals (CIs) were calculated to assess the relative population-level impact of the use of hormonal contraceptives on HIV-1 seroconversion rates and on pregnancy rates. Women who reported using hormonal contraceptives at enrolment in the trial had a higher risk of HIV-1 seroconversion (adjusted hazards ratio: 1.24; 95% CI: 0.97-1.58) than women who reported using other types of contraceptives at enrolment. At the population level, the use of hormonal contraceptives (pills or injectables) at baseline and during study follow-up accounted for approximately 20% (95% CI: 16-22) of HIV-1 seroconversions. However, the partial PAR indicated a relative impact of 12% (95% CI: 9.0-15.7). On the other hand, 72% (95% CI: 66-77) of the pregnancies could have been avoided if all women had used hormonal contraceptives. Women using hormonal contraceptives need comprehensive counselling on simultaneous prevention of HIV-1 infection.

Improving hepatitis B vaccination rates in the hemodialysis population

More than 2 billion people worldwide are estimated to have been infected with hepatitis B virus (HBV), and of these, 360 million are chronic carriers of HBV (Table 1). 1. Proceedings of the European Association for the Study of the Liver (EASL) International Consensus Conference on Hepatitis B. September 14-16, 2002. Geneva, Switzerland. J Hepatol. 2003; 39: S1-S235 PubMed Google Scholar HBV is transmitted through exposure to infected blood or body fluids, and untreated exposure has a 30% risk of seroconversion. 2. Edey M. Barraclough K. Johnson D.W. Review article: hepatitis B and dialysis. Nephrology. 2010; 15: 137-145 Crossref PubMed Scopus (101) Google Scholar If primary infection occurs, about 95% of immunocompetent adults will experience a self-limiting disease and subsequently become immune to future infection. However, patients infected with human immunodeficiency virus (HIV) or who receive hemodialysis are at a higher risk of contracting HBV infection and becoming chronic carriers of HBV. 2. Edey M. Barraclough K. Johnson D.W. Review article: hepatitis B and dialysis. Nephrology. 2010; 15: 137-145 Crossref PubMed Scopus (101) Google Scholar , 3. Advisory Committee on Immunization Practices. A comprehensive immunization strategy to eliminate transmission of hepatitis B virus infection in the United States: recommendations of the Advisory Committee on Immunization Practices (ACIP) Part II: immunization of adults. MMWR Recomm Rep. 2006; 55: 1-33 PubMed Google Scholar People who develop chronic HBV infection are at risk for hepatocellular carcinoma, cirrhosis of the liver, and death, as well as serve as a means for transmitting infection to other unvaccinated or undervaccinated individuals. 3. Advisory Committee on Immunization Practices. A comprehensive immunization strategy to eliminate transmission of hepatitis B virus infection in the United States: recommendations of the Advisory Committee on Immunization Practices (ACIP) Part II: immunization of adults. MMWR Recomm Rep. 2006; 55: 1-33 PubMed Google Scholar The most efficient and effective manner by which to prevent HBV infection is vaccination. The Centers for Disease Control and Prevention (CDC) and its Advisory Committee on Immunization Practices (ACIP) have identified high-risk populations for which vaccination is recommended: intravenous drug users, individuals engaging in high-risk sexual behavior, patients in long-term care facilities, and patients with chronic liver disease, with HIV infection, or who receive hemodialysis. In addition, health care workers are at high-risk of contracting HBV through occupational exposure and, according to CDC recommendations, should receive vaccination against HBV. 3. Advisory Committee on Immunization Practices. A comprehensive immunization strategy to eliminate transmission of hepatitis B virus infection in the United States: recommendations of the Advisory Committee on Immunization Practices (ACIP) Part II: immunization of adults. MMWR Recomm Rep. 2006; 55: 1-33 PubMed Google Scholar

High HIV Incidence and Sexual Behavior Change among Pregnant Women in Lilongwe, Malawi: Implications for the Risk of HIV Acquisition

BackgroundHIV incidence is higher among pregnant women than their non-pregnant counterparts in some sub-Saharan African settings. Our aims were (1) to estimate HIV incidence during pregnancy and (2) to compare sexual activity between pregnant, postpartum, and non-pregnant women.MethodsWe examined a retrospective cohort of 1087 women to identify seroconverters using antenatal and labor ward HIV test results. We also conducted a cross-sectional survey, including a quantitative questionnaire (n = 200) and in-depth interviews (n = 20) among women in early pregnancy, late pregnancy, postpartum, and non-pregnancy. Outcomes included measures of sexual activity, reported spouse’s risky behavior, and beliefs about abstinence.Results11 of 1087 women seroconverted during pregnancy yielding a 1% seroconversion risk and an incidence rate of 4.0/100 person years (95% CI 2.2–7.2). The reported sexual activity of the early pregnancy and non-pregnancy groups was similar, but significantly higher than the late pregnancy and postpartum groups (p<0.001). During pregnancy, sex acts decreased as gestation increased (p = 0.001). There was no reported difference in the spouse’s risky behavior. Most women believed that sex should cease between the 6th and 8th month of pregnancy and should not resume until 6 months postpartum. Some talked about conflict between their cultural obligation to abstain and fear of HIV infection if their spouses find other partners.ConclusionsHIV incidence is high among pregnant women in Malawi, and sexual activity decreases during pregnancy and postpartum. Pregnant women need to be informed of their increased risk for HIV and the importance of using condoms throughout pregnancy and the postpartum period.

Blood‐borne viruses in the haemodialysis‐dependent population attending Top End Northern Territory facilities 2000–2009

To describe the incidence and prevalence of blood-borne viruses (BBV) including: hepatitis B virus (HBV), hepatitis C virus (HCV), human immunodeficiency virus (HIV) and human T-cell leukaemia virus type-1 (HTLV) in the haemodialysis-dependent population of the Top End of the Northern Territory (TENT). We retrospectively reviewed the serology of BBV in a longitudinal fashion in the haemodialysis-dependent population treated in the TENT of Australia from 2000 to 2009 inclusive. HBV, HCV, HIV and HTLV serology on commencement of dialysis and at exit or January 2010, whichever was earlier, as well as demographic details were collected. Patients with a change in serological status had all serology reviewed. Four-hundred and forty patients were included in the analysis. Of these, 84.3% were Indigenous and 55.4% female, with a median age of 50 (IQR 43-59) years at the commencement of haemodialysis. Evidence of past HBV infection was documented in 42.7% and 8.9% were hepatitis B surface antigen-positive. Positive serology for HTLV was documented in 2.2%, 1.6% were hepatitis C antibody-positive and no individual was HIV-positive. Three patients had a definite change in their HBV serology over time; this equates to an absolute seroconversion risk of 0.1 per 100 person years or 0.0006 per dialysis episode. In this cohort, there was a high rate of past and current hepatitis B infection but low rates of seroconversion while on haemodialysis.

Immunoglobulin M seropositivity for Toscana virus in a random population sample in Sicily

High Toscana virus (TOSV) antibody seropositivity rates have been documented in the last decade, especially in the Mediterranean area. It is unclear if these rates are associated with a recent or past exposure to the virus. This is of importance, as primary infection can cause neurologic complications, especially in adults. The aim of the present study was to assess the current active TOSV circulation in western Sicily. A cross-sectional seroprevalence study was conducted on 271 individuals aged 4-92 years, sampled from the general population of a small city. Each participant completed a self-administered questionnaire and provided serum, which was analyzed for the presence of specific anti-TOSV IgM and IgG. Anti-TOSV IgM was detected in eight (3.0%) participants, of whom only three had anti-TOSV IgG. The prevalence of anti-TOSV IgM was highest in subjects aged 25-34 and 35-44 years (7.1% and 4.8%, respectively). All subjects positive for anti-TOSV IgM were resident in the suburban area. The detection of IgM documented the circulation of TOSV, a Phlebovirus, in a random population sample of Sicilian adults. The highest risk of TOSV seroconversion in subjects living in the suburbs appears to suggest a high density of TOSV vectors in peri-urban areas.

Assessing and evaluating the combined impact of behavioural and biological risk factors for HIV seroconversion in a cohort of South African women

In this prospective study, we aimed to investigate and evaluate the impact of combinations of behavioural and biological risk factors on HIV acquisition in a cohort of women. Demographic, sexual and biologic risk factors including HIV seroconversion results from 1485 HIV negative women who were enrolled in a HIV prevention trial were used. First, Cox regression models were used to create a prediction model and weighted scoring system. Second, internal validation data-set was used to evaluate the performance characteristics of the model prospectively. In the prediction model, an increasing number of lifetime sexual partners, women who were classified as in a “high risk behavior” group, and those who were not cohabitating with their partners were consistently associated with increased risk of HIV acquisition. Among the baseline biological factors, genital epithelial disruption, genital signs and symptoms, genital discharge and detecting edema, erythma or warts in vulva were all associated with HIV seroconversion. High scores were associated with increased risk of HIV seroconversion. A cut-point score of 15 (out of 44) or higher distinguished an “increased risk” group with a sensitivity of 88%. This study presents reasonable robust analyses for investigating and evaluating epidemiological measures on HIV infection. Results from this study may be included as part of a health promotion to prompt those who are at increased risk of HIV infection which may potentially lead to increased uptake and frequency of testing.

Needle exchange and the HIV epidemic in Vancouver: Lessons learned from 15 years of research

During the mid-1990s, Vancouver experienced a well characterized HIV outbreak among injection drug users (IDU) and many questioned how this could occur in the presence of a high volume needle exchange program (NEP). Specific concerns were fuelled by early research demonstrating that frequent needle exchange program attendees were more likely to be HIV positive than those who attended the NEP less frequently. Since then, some have misinterpreted this finding as evidence that NEPs are ineffective or potentially harmful. In light of continuing questions about the Vancouver HIV epidemic, we review 15 years of peer-reviewed research on Vancouver's NEP to describe what has been learned through this work. Our review demonstrates that: (1) NEP attendance is not causally associated with HIV infection, (2) frequent attendees of Vancouver's NEP have higher risk profiles which explain their increased risk of HIV seroconversion, and (3) a number of policy concerns, as well as the high prevalence of cocaine injecting contributed to the failure of the NEP to prevent the outbreak. Additionally, we highlight several improvements to Vancouver's NEP that contributed to declines in syringe sharing and HIV incidence. Vancouver's experience provides a number of important lessons regarding NEP. Keys to success include refocusing the NEP away from an emphasis on public order objectives by separating distribution and collection functions, removing syringe distribution limits and decentralizing and diversifying NEP services. Additionally, our review highlights the importance of context when implementing NEPs, as well as ongoing evaluation to identify factors that constrain or improve access to sterile syringes.

Assessment of organ transplants from donors with markers of hepatitis B

Organ transplantation (TX) is currently a therapeutic alternative in the management of end-stage or lethal diseases and, in some cases, for improving the quality of life and reducing the complications of chronic conditions. The scarcity of organ grafts or donors due to the limited number of deceased donors or to a lack of compatible living donors is one of the main limitations for the execution of organ TX. In Brazil, there is a great disparity between the number of patients on waiting lists and TX procedures, especially for liver and kidney TX. As a result of this inequality, grafts from donors who are considered marginal or not ideal have been used, including those with higher risk of failure following TX or those with potentially transmissible infections, involving donors with positive serologic markers for the hepatitis B virus (HBV). Donors who are positive for HBV markers have been routinely used in some TX centers. Four aspects should be considered for the assessment of the risk-benefit ratio of this procedure: 1. donor serologic profile, 2. recipient serologic profile, 3. TX variety and 4. the use of preventive therapy with human-specific HBV immunoglobulin and/or antiviral drugs. To establish recommendations, our group held discussions based on the data available in the medical literature and on the accumulated experience of the TX units at Hospital das Clinicas da Faculdade de Medicina da Universidade de Sao Paulo. The definitions of serologic profiles for donors and recipients are described in Tables 1 and ​and2,2, respectively. The following transplants have been evaluated: liver, kidney, heart, lung, and hematopoietic stem cell transplants (HSCT). The IDSA (Infectious Diseases Society of America) rating system was used to assess the quality of evidence for graft acceptance and to identify the appropriate preventive strategy. Table 1 Definitions of HBV serologic profiles – Donors. Table 2 Definitions of HBV serologic profiles – Recipients. 1. Liver TX HBsAg-positive donor: few reports are available, under particular circumstances, and there is a high risk of “de novo” HBV infection. HBc-Ab-positive donor: HBsAg-positive recipient: regardless of the donor's serologic profile, this recipient must be administered combined prophylaxis with HBIG and an antiviral drug. The risk of viral reactivation does not seem to be increased by the involvement of an HBc-Ab-positive donor. Recipients who are positive for HBc-Ab and HBs-Ab: there are no reports of “de novo” HBV infection, with or without prophylaxis. Recipients with isolated HBc-Ab or a history of vaccination: the risk of “de novo” HBV is reduced in case series that described lamivudine and/or HBIG prophylaxis. Naive recipient: group at highest risk; case series that described lamivudine and HBIG prophylaxis have demonstrated a reduction in risk. Kidney TX The largest case series of donors with positive serologic markers for HBV were published in kidney TX. However, some studies describe only the post-TX clinical course and fail to assess HBV serology. HBsAg-positive donor: among 48 donors, “de novo” HBV infection has been detected in three recipients with variable pre-TX serologic profiles, while liver enzyme elevation has been detected in nine recipients. HBc-Ab-positive donor: HBsAg-positive recipient: when lamivudine is used as preventive therapy, the clinical evolution is similar to that of recipients whose donors have negative HBV serology. Recipients with isolated HBc-Ab: without any prophylaxis, the seroconversion of HBsAg has been observed in 0.5% of recipients after TX. No reports have described seroconversion under lamivudine prophylaxis. Vaccinated or Naive recipient: after TX, without any prophylaxis, seroconversion of HBc-Ab occurs in 2% of cases, and seroconversion of HBsAg occurs in less than 0.5% - without any impact on the clinical course. No reports have described seroconversion under lamivudine prophylaxis. Heart TX There are two case series on heart TX that report lamivudine prophylaxis in some recipients. Only one case of “de novo” HBV infection is reported in a naive recipient with an HBsAg-positive donor. Lung TX In two small case series of HBc-Ab-positive donors, no cases of recipient post-TX seroconversion were described. Among the two case series, one involved lamivudine prophylaxis. Hematopoietic Stem Cell Transplant In HSCT, the most relevant consideration is the risk of reverse seroconversion (loss of HBs-Ab after TX). HBsAg-positive donor: in a study of HBsAg-negative recipients with a historical control group, the risk of “de novo” HBV was significantly reduced with lamivudine prophylaxis. HBc-Ab-positive donor: when the bone marrow donor is naturally immunized (HBc-Ab and HBs-Ab positive), there is an unmistakable reduction in the risk of reverse seroconversion.

The rising prevalence of prescription opioid injection and its association with hepatitis C incidence among street‐drug users

To examine trends in prescription opioid (PO) injection and to assess its association with hepatitis C virus (HCV) seroconversion among injection drug users (IDUs). Prospective cohort study. Montreal, Canada. HCV-negative IDUs at baseline, reporting injection in the past month. Semi-annual visits included HCV antibody testing and an interview-administered questionnaire assessing risk behaviours. HCV incidence rate was calculated using the person-time method. Time-updated Cox regression models were conducted to examine predictors of HCV incidence. The proportion of IDUs reporting PO injection increased from 21% to 75% between 2004 and 2009 (P < 0.001). Of the 246 participants (81.6% male; mean age 34.5 years; mean follow-up time 23 months), 83 seroconverted to HCV [incidence rate: 17.9 per 100 person-years; 95% confidence interval (CI) 14.3, 22.1]. Compared to non-PO injectors, PO injectors were more likely to become infected [adjusted hazard ratio (AHR): 1.87; 95%CI:1.16, 3.03]. An effect modification was also found: PO injectors who did not inject heroin were more likely to become infected (AHR: 2.88; 95%CI: 1.52, 5.45) whereas no association was found for participants using both drugs (AHR: 1.19; 95% CI: 0.61, 2.30). Other independent predictors of HCV incidence were: cocaine injection, recent incarceration and >30 injections per month. Prescription opioid injectors who do not inject heroin are at greater risk for HCV seroconversion than are those injecting both heroin and prescription opioids. Important differences in age, behaviour and social context suggest a need for targeted outreach strategies to this population.

The effects of injectable hormonal contraceptives on HIV seroconversion and on sexually transmitted infections

To investigate the association between hormonal contraceptives and risk of HIV-1 seroconversion and prevalence of other sexually transmitted infections. Prospective cohort. The study population was 2,236 HIV-negative women who were screened in a biomedical intervention trial in Durban, South Africa. The association between the use of hormonal contraceptives and risk of HIV-1 seroconversion was modeled using Cox proportional hazards regression analysis. Prevalence of Chlamydia trachomatis and Neisseria gonorrhoeae infections were assessed using logistic regression models. Hormonal injectables were the most common method of contraceptives (46.47%) followed by condom use (28.04%). Overall, compared with women who reported using condoms or other methods as their preferred form of contraceptive, those who reported using hormonal contraceptives (injectables and oral pills) were less likely to use condoms in their last sexual act. Using hormonal injectables during the study was significantly associated with increased risk for HIV-1 infection [adjusted hazard ratio 1.72, 95% confidence interval (CI) 1.19-2.49, P = 0.005]; hormonal injectables were also significantly associated with higher prevalent of C. trachomatis infections (adjusted odds ratio 2.46, 95% CI 1.52-3.97, P < 0.001). Hormonal injectables are highly effective and well tolerated family planning methods and have played an important role in reducing unplanned pregnancies and maternal and infant mortality. However, they do not protect against HIV-1 and other sexually transmitted infections. This study reinforces the importance of comprehensive contraceptive counseling to women about the importance of dual protection, such as male condoms and hormonal contraceptives use.

Experience in international clinical research: the HIV Prevention Trials Network.

The HIV Prevention Trials Network (HPTN) is supported by the NIH to conduct randomized clinical trials to assess the efficacy of HIV prevention strategies and technologies to reduce HIV transmission between adults. A special focus of attention is on the use of antiretroviral drugs to prevent HIV transmission, both by reducing infectiousness among HIV-infected persons taking combination antiretroviral therapy (cART) and also by reducing susceptibility among HIV-uninfected persons taking antiretrovirals for pre-exposure prophylaxis. Studies may be developmental in nature to assess novel ideas for interventions or for assessing trial feasibility. However, pivotal efficacy trials to test HIV-specific prevention strategies and technologies are the main HPTN priority. Examples include a major protocol investigating the impact of expanded testing and linkage to care on HIV surveillance indicators in the USA (HPTN 065). Another protocol is addressing similar issues while also investigating how combinations of prevention approaches are best deployed to make a community-level impact in southern Africa (HPTN 071). HPTN 068 is evaluating a novel conditional cash transfer structural intervention to increase school completion rates in young girls and thereby reduce their HIV risk. Studies outside the US address the epidemic in most at-risk populations and include an assessment of opiate agonist therapy to reduce risk of HIV seroconversion among injection drug users (HTPN 058), methods to increase HIV testing rates (HTPN 043), as well as methods for reducing high-risk behaviors, and increasing adherence to cART in HIV-infected individuals (HPTN 062 and HPTN 063, respectively). The recent HPTN 052 study demonstrated that a 96% reduction in HIV transmission could be achieved between serodiscordant sexual partners by providing the infected partners with cART at a CD4(+) cell count (350-550/µl) above the level that would usually qualify them for therapy in low- and middle-income countries. The immediate relevance to public health policy showcased in these trials is a paradigm for the HPTN: design and conduct of clinical trials using available licensed tools that can be rapidly translated for implementation ('Prevention NOW!').

Risk of seroconversion to peste des petits ruminants (PPR) and its association with species, sex, age and migration

The present investigation included a detailed description of risk of PPR in small ruminants and its association with various host and environmental factors. A total of 432 serum samples comprising of 216 samples (108 sheep and 108 goats) from migratory and 216 samples (108 sheep and108 goats) from non-migratory flocks of sheep and goat were screened for PPR antibodies using competitive-ELISA. The overall seroprevalence of PPR in migratory flocks (33.79%) was significantly (p<0.05) higher as compared to non-migratory flocks (24.07%). The seroprevalence of PPR in sheep (29.16%) was higher than that of goat (28.70%) but the difference was non-significant, age wise seroprevalence was significantly (p<0.05) higher in >12 months age group (39.58%) followed by 8–12 months (26.38%) and 4–8 months (20.83%) age group. On risk factor analysis, it was observed that at 95% confidence interval, odd ratio was higher in migratory (1.610) than non-migratory (0.612) flocks, in sheep (1.023) than goats (0.978), the value of odd ratio was higher in >12 months age group (2.490 and 1.828) as compared to 4–8 months and 8–12 months, respectively. The overall sex wise seroprevalence in males (33.33%) was significantly (p<0.05) higher than in females (24.53%) and also risk factor analysis revealed a higher odd ratio in males (1.538, overall; 1.581, migratory and 1.503, non-migratory) than in females (0.650, overall; 0.633, migratory and 0.655 non-migratory). The present study relates the variation of PPR risk in association with species, age, sex, sheep and goat husbandry practices.

A prospective study of frequency and correlates of intimate partner violence among African heterosexual HIV serodiscordant couples.

Intimate partner violence (IPV) is common worldwide and is an important consideration in couples HIV voluntary counseling and testing (CVCT), especially for HIV-serodiscordant couples (i.e. in which only one member is HIV-infected). Prospective study of 3408 HIV-serodiscordant couples (2299 in which the HIV-infected partner was female) from seven countries from East and Southern Africa. At quarterly visits during up to 2 years of follow-up, participants were asked, separately, about IPV perpetrated against them by their partner during the prior 3 months. Correlates of IPV were determined by generalized estimating equations. The majority of couples were married and living together, with an average duration of partnership of approximately 5 years. More than 39,000 quarterly visits were recorded. IPV was reported in 2.7% of visits by HIV-infected women, 2.2% by HIV-uninfected women, 0.9% by HIV-infected men, and 0.7% by HIV-uninfected men. The majority of IPV reports were verbal or a combination of verbal and physical violence. Those who were HIV-infected were more likely to report IPV [for women adjusted odds ratio (AOR) 1.33, P = 0.043; for men AOR 2.20, P = 0.001], but IPV was not significantly associated with risk of HIV seroconversion in HIV-uninfected participants. IPV incidence decreased during follow-up (P < 0.001). During up to 2 years of prospective follow-up, most persons in stable HIV-serodiscordant partnerships who had undergone CVCT did not report IPV. A modest increased risk of IPV was seen for HIV-infected partners, both female and male.

Occupational transmission of hepatitis C in healthcare workers and factors associated with seroconversion: UK surveillance data

The study aims were to describe a case series of occupationally acquired hepatitis C (HCV) infections in UK healthcare workers and examine factors associated with transmission using exposure data reported to the Health Protection Agency between July 1997 and December 2007. Fifteen reported cases of documented HCV seroconversion occurred after percutaneous exposure, the majority from hollow-bore needles used in the source patient's vein or artery and contaminated with blood or blood-stained fluid. The seroconversion rate was 2.2% (14/626). In multivariable analysis of healthcare workers with percutaneous exposure to blood or blood-stained fluid, we demonstrate that blood sampling procedures (odds ratio [OR], 5.75; 95% CI, 1.33-24.91; P = 0.01) and depth of injury (OR for deep vs superficial injury, 21.99; 95% CI, 2.02-239.61; P = 0.02) are independently associated with a greater risk of HCV seroconversion. This is the first UK study of occupationally acquired HCV in healthcare workers. It has reinforced our knowledge of risk factors for HCV transmission. Most of these exposures and transmissions were preventable. Healthcare employers should provide regular education on the risks of occupational exposure and prevention through standard infection control procedures. They should ensure the availability of effective prevention measures and facilitate prompt reporting and adequate follow-up of exposures.

Apparent prevalence of antibodies to Coxiella burnetii (Q fever) in bulk tank milk from dairy herds in southern Belgium

In 2006, a cross-sectional survey was carried out in 206 herds in southern Belgium to estimate the proportion of herds with Q fever-seropositive bulk tank milk (BTM), i.e. herds with an intra-herd seroprevalence >10%. Of the tested herds, 119 (57.8%; 95% CI: 51.1-64.4%) were seropositive. Most had a low antibody titre. Of these herds, 50 were randomly subjected to a real time Coxiella burnetii PCR analysis. The proportion of herds excreting Coxiella in BTM was 30.0% with only 2.0% of herds having a high level of shedding. An additional questionnaire and logistical regression identified some factors which increased the risk of BTM seroconversion (in heifers, drinking water from watercourse or well water) and some which decreased it (in heifers, tie- and free-stalling, and animals of all age in the same shed; in heifers and cows, shed disinfection).