The impact of sex partners' HIV status on HIV seroconversion in a prospective cohort of injection drug users

OBJECTIVE AND DESIGN: The identification of individuals at highest risk of HIV infection is critical for targeting prevention strategies. We evaluated the HIV status of the sex partners of injection drug users (IDUs) and rates of subsequent HIV seroconversion among a prospective cohort study of IDUs. METHODS: We performed an analysis of the time to HIV infection among baseline HIV-negative IDUs enrolled in the Vancouver Injection Drug Users Study. IDUs were stratified based on whether or not they reported having an HIV-positive sex partner. Kaplan-Meier methods were used to estimate cumulative HIV incidence rates, and Cox regression was used to determine adjusted relative hazards (RHs) for HIV seroconversion. RESULTS: Of 1013 initially HIV-negative IDUs, 4.8% had an HIV-positive partner at baseline. After 18 months, the cumulative HIV incidence rate was significantly elevated among those who reported having an HIV-positive sex partner (23.4% vs. 8.1%; log-rank P < 0.001). In a Cox regression model adjusting for all variables that were associated with the time to HIV infection in univariate analyses, including drug use characteristics, having an HIV-positive sex partner (RH = 2.42 [95% confidence interval: 1.30 to 4.60]; P = 0.005) remained independently associated with time to HIV seroconversion. CONCLUSIONS: Having an HIV-positive sex partner was strongly and independently associated with seroconversion after adjustment for risk factors related to drug use. Our findings may aid public health workers in their efforts to identify IDUs who should be targeted with education and prevention efforts and indicate the need for ongoing development of prevention interventions for IDU sex partners who are HIV discordant.     

Evolution of couples' voluntary counseling and testing for HIV in Lusaka, Zambia

BACKGROUND:: We describe promotional strategies for couples' voluntary HIV counseling and testing (CVCT) and demographic risk factors for couples in Lusaka, Zambia, where an estimated two thirds of new infections occur in cohabiting couples. PRINCIPAL FINDINGS:: CVCT attendance as a function of promotional strategies is described over a 6-year period. Cross-sectional analyses of risk factors associated with HIV in men, women, and couples are presented. Community workers (CWs) recruited from couples seeking CVCT promoted testing in their communities. Attendance dropped when CW outreach ended, despite continued mass media advertisements. In Lusaka, 51% of 8500 cohabiting couples who sought HIV testing were concordant negative for HIV (MF) and 26% concordant positive (MF); 23% had 1 HIV-positive partner and one HIV-negative partner, with 11% HIV-positive man/HIV-negative woman (MF) and 12% HIV-negative man/HIV-positive woman (FM). HIV infection was associated with men's age 30 to 39, women's age 25 to 34, duration of union <3 years, and number of children <2. Even among couples with either 1 or 2 or no risk factors, HIV prevalence was 45% and 29%, respectively. CONCLUSIONS:: Many married African adults do not have high-risk profiles, nor realize that only 1 may be HIV positive. Active and sustained promotion is needed to encourage all couples to be jointly tested and counseled.     

Randomized trial of vitamin supplements in relation to vertical transmission of HIV-1 in Tanzania

BACKGROUND: Observational studies suggest that poor nutritional status among HIV-infected pregnant women is associated with a higher risk of vertical transmission of HIV. METHODS: We randomized 1083 pregnant women infected with HIV-1 in a double-blind, placebo-controlled trial to examine the effects of supplements of vitamin A and/or multivitamins (excluding vitamin A) using a 2-x-2 factorial design. We report the effects of the supplements on HIV infection defined using polymerase chain reaction (PCR), or death up to 6 weeks postpartum. RESULTS: Of babies in the multivitamin arm 38, (10.1%) were HIV-positive at birth compared with 24 (6.6%) in the no-multivitamin arm (relative risk [RR] = 1.54; 95% CI, 0.94-2.51; p = .08). Of babies born to mothers in the vitamin A arm, 38 (10.0%) were HIV-positive at birth compared with 24 (6.7%) in the no-vitamin A arm (RR, 1.49; 95% CI, 0.91-2.43; p = 0.11). Neither multivitamins nor vitamin A had an effect on HIV status at 6 weeks among those who were HIV-negative at birth (RR = 1.04; 95% CI, 0.65-1.66; p = 0.88) and (RR = 1.30; 95% CI, 0.80-2.09; p = .29, respectively). Similarly, neither supplement was associated with being either HIV-infected or dead at birth (RR, 0.98; 95% CI, 0.76-1.27; p = .89 and RR, 1.01; 95% CI, 0.78-1.31; p = .95, respectively. A beneficial effect of multivitamins on birth weight was limited to babies who were HIV-negative at birth; babies in the multivitamin arm weighed +94 g more compared with those in the no-multivitamin arm (p = .02). Among babies who were HIV-positive at birth, the corresponding difference was -31 g (p = .82). CONCLUSIONS: Vitamin A and multivitamins did not affect the risk of vertical transmission of HIV in utero nor during the intrapartum and early breastfeeding periods. Multivitamins resulted in a significant improvement in birth weight of babies who were HIV-negative at birth but had no effect among those who were HIV-positive. The effect of vitamin supplements on HIV transmission through breastfeeding and on clinical progression of HIV disease is yet to be ascertained.     

HIV transmission risk among serodiscordant couples: a retrospective study of former plasma donors in Henan, China

OBJECTIVES: To estimate the HIV incidence and assess the behavioral, clinical, and quality-of-life risk factors for HIV transmission among serodiscordant couples from Henan Province, China. METHODS: Between January 2006 and December 2008, initially seronegative spouses were tested for HIV at six month intervals. Retrospectively identified subjects were interviewed through face-to-face questionnaire. Cox proportional-hazards model was used to assess the relationship between risk factors and HIV seroconversion. RESULTS: Out of 1927 couples, 84 (4.3%) seroconversions occurred, representing a seroconversion rate of 1.71 per 100 person-years. Seroconversion rates increased over time. Not always using condoms (RR=8.42; 95% CI, 4.83-14.67), sexual activity ≥ 4 times per month (RR=5.24; 95% CI, 2.55-10.77), not switching anti-retroviral treatment regimen (RR=1.99; 95% CI, 0.85-4.65), and a quality of life score <12 on the psychological domain (RR=2.33; 95% CI, 1.21-4.48) were associated with increased risk of seroconversion. Seventy one percent of index spouses were on ART. There was no association between rate of HIV seroconversion and last recorded CD4 cell count level of the index spouse. CONCLUSIONS: Effective HIV prevention interventions targeting discordant couples should focus on sustaining health education, increasing psychosocial support services, and increasing medication adherence monitoring.     

Partner-specific sexual behavioral differences between phase 3 HIV vaccine efficacy trial participants and controls: Project VISION

OBJECTIVE: To assess and compare sexual behaviors using partner-specific data between HIV-negative men who have sex with men (MSM) recruited for an HIV vaccine efficacy trial and a control group. METHODS: HIV-negative MSM from an HIV vaccine trial (n = 525) and controls (n = 732) were recruited by similar strategies and interviewed about behaviors with the 3 most recent partners in the past 6 months, obtained by audio computer-assisted self-interview (A-CASI). RESULTS: Vaccine trial participants were more likely than controls to report an HIV-positive partner (24.7% and 14.1%, respectively) or an HIV-positive primary partner (16.1% and 6.8%, respectively) and were less likely to report occasional or single-time partners of unknown HIV status (51.6% and 63.2%, respectively; P < 0.05 for each comparison). Vaccine trial participants more often reported receptive unprotected anal intercourse (UAI) during their last sexual encounter with an HIV-positive partner (adjusted odds ratio [OR] = 2.7, 95% confidence interval [CI]: 1.0 to 7.9). Most believed their HIV-positive partners were receiving antiretroviral treatment (ART), however, and after adjustment for perceived ART use, the association between vaccine study participation and receptive UAI with an HIV-positive partner was not significant. CONCLUSIONS: High-risk sexual behavior was reported by many VAX004 participants and controls. Differences between vaccine trial and control participants in the highest risk per contact behavior, receptive UAI with HIV-positive partners, was partly accounted for by perceived ART use. Partner level data are useful in refining risk assessment, which is important in the evaluation of HIV vaccine and other prevention trials.     

Combination therapies for HIV and sexual risk behavior among gay men

OBJECTIVE: To examine optimism in the light of recent advances in HIV treatment among gay men and its association with sexual risk behavior. METHODS: An anonymous questionnaire was completed by gay men who visited gyms in central London in March and April 1998 regarding their HIV status, unprotected anal intercourse (UAI) in the previous 3 months, and their response on a five-point linear scale to two measures of optimism: "I am less worried about HIV now that treatments have improved," and "I believe that new drug therapies make people with HIV less infectious." RESULTS: Two thirds of the men (67.5%, 522 of 773) did not agree with the statement, "I am less worried about HIV now that treatments have improved," and only 42 (5.4%) said they agreed quite a lot or a lot. HIV-positive men were more likely to agree with this statement than HIV-negative men (p = .001) and men who had never been tested (p < .001). There was no association between agreement with this statement and frequency of UAI among HIV-positive or never-tested men (p > .3); there was, however, a positive association among HIV-negative men who reported UAI with a partner of unknown or discordant status (p = .003). The vast majority of men (81.4%; 634 of 779) did not agree with the statement, "I believe that new drug therapies make people with HIV less infectious." Regardless of HIV status, no significant association was seen between agreement with this statement and frequency of UAI (p > .1 for all comparisons). CONCLUSION: Most gay men surveyed in central London gyms did not endorse the optimism statements concerning improved treatments or reduced infectivity. Although HIV-positive gay men were more likely to be optimistic than other men, there was no association between their optimism and sexual risk behavior. Among HIV-negative men, optimism around improved treatments (but not around reduced infectivity) was associated with UAI with a partner of unknown or discordant HIV status. For some HIV-negative men in London, optimism in the light of recent advances in HIV treatment may have triggered, or have been used as a justification for, sexual risk-taking.     

Sexual risk, nitrite inhalant use, and lack of circumcision associated with HIV seroconversion in men who have sex with men in the United States

Men who have sex with men (MSM) continue to account for the largest number of new HIV infections in the United States, but limited data exist on independent risk factors for infection beyond the early 1990s. The HIV Network for Prevention Trials Vaccine Preparedness Study enrolled 3257 MSM in 6 US cities from 1995 to 1997. HIV seroincidence was 1.55 per 100 person-years (95% confidence interval: 1.23-1.95) over 18 months of follow-up. On multi-variable analysis using time-dependent covariates, independent risk factors for HIV seroconversion were increased number of reported HIV-negative male sex partners (adjusted odds ratio (AOR) = 1.14 per partner, population attributable risk (PAR) = 28%), nitrite inhalant use (AOR = 2.2, PAR = 28%), unprotected receptive anal sex with an HIV unknown serostatus partner (AOR = 2.7, PAR = 15%) or HIV-positive partner (AOR = 3.4, PAR = 12%), protected receptive anal sex with an HIV-positive partner (AOR = 2.2, PAR = 11%), lack of circumcision (AOR = 2.0, PAR = 10%), and receptive oral sex to ejaculation with an HIV-positive partner (AOR = 3.8, PAR = 7%). Having a large number of male sex partners, nitrite inhalant use, and engaging in receptive anal sex explained the majority of infections in this cohort and should be targeted in prevention strategies for MSM.     

Transmission behaviors of recently HIV-infected men who have sex with men

OBJECTIVES: Analyze postdiagnosis behaviors of recently HIV-infected men who have sex with men (MSM). METHODS: Recently HIV-infected MSM were interviewed at 6 weeks (n = 153) and 3 months (n = 113) after diagnosis. Behaviors from baseline to follow-up were compared; multivariate logistic regression identified associations between baseline characteristics and behavior at follow-up. RESULTS: At follow-up, MSM reported a significantly lower mean of partners (7.9 vs. 5.2) and lower means of 1-time (1.9 vs. 0.8), unknown (3.7 vs. 2.6), and acquaintance (1.1 vs. 0.5) partners than at baseline. In multivariate analyses, unprotected anal intercourse (UAI) with the last partner at follow-up was more likely if the last partner at baseline was a main partner (odds ratio [OR] = 2.94, 95% confidence interval [CI]: 1.04 to 8.33) or HIV-positive partner (OR = 3.36, 95% CI: 1.27 to 8.88) but less likely if, at follow-up, the last partner was HIV-negative (OR = 0.28, 95% CI: 0.08 to 1.00) or of unknown HIV status (OR = 0.23, 95% CI: 0.08 to 0.71), the participant had a history of nonconsensual sex (OR = 0.25, 95% CI: 0.09 to 0.72), or the participant had more than 1 partner (OR = 0.28, 95% CI: 0.09 to 0.86). More than 1 partner at follow-up was associated with no main partner at baseline or follow-up (OR = 2.76, 95% CI: 1.12 to 6.78), more partners in the last 12 months (OR = 1.02, 95% CI: 1.01 to 1.04), and UAI with the last partner (OR = 0.36, 95% CI: 0.14 to 0.90). CONCLUSIONS: After diagnosis, some but not all recently HIV-infected MSM reduced risky sexual behavior permitting potential HIV transmission.     

Use of a public sexually transmitted disease clinic by known HIV-positive adults: decreased self-reported risk behavior and increased disease incidence

High-risk sexual behavior by HIV-positive individuals is an important factor contributing to the spread of the HIV epidemic. We conducted a retrospective chart review to compare self-reported sexually transmitted disease (STD) risk behavior and clinic diagnoses of known HIV-positive clients attending Miami-Dade County STD clinics with those of uninfected controls. One hundred ninety-one HIV-positive clients and 191 HIV-negative controls, 130 (68.1%) men and 61 (31.9%) women, were included in the analysis. HIV-positive clients were more likely than controls to report no sexual activity in the last 2 months (odds ratio [OR] = 2.6, 95% confidence interval [CI]: 1.5-4.5) or, if active, to report condom use at last sexual intercourse (OR = 3.1, CI: 1.9-5.3). However, HIV-positive clients were more likely to be diagnosed with infectious syphilis (OR = 13.0, CI: 1.6-99.4) and/or gonorrhea (OR = 2.1, CI: 1.1-4.2) than controls. This may be a result of overreporting of condom use or sexual activity in high-risk sexual networks with inefficient use of condoms. Ongoing sexual risk behavior and access to HIV primary care are important issues in this population.     

Risk factors for incident HIV infection among anonymous HIV testing site clients in Santos,Brazil: 1996-1999

OBJECTIVES: To determine temporal trends in HIV infection and risk factors among persons seeking anonymous HIV testing in Santos, Brazil. METHODS: Data and sera from persons testing for HIV from 1996 to 1999 were used. Exposures were abstracted from HIV testing risk assessments. Stored HIV-positive sera were tested to identify recently acquired HIV infection using a serologic testing algorithm for detecting recent HIV seroconversion (STARHS). Independent associations between exposures and recently acquired HIV infection were determined using multivariate analyses. RESULTS: Overall, estimated HIV incidence was 2.0% (95% CI: 1.1-3.5) for the 4-year period: 1.2% (95% CI: 0.5-2.6) in women and 2.7% (95% CI: 1.3-5.0) in men. Incidence increased among women but remained stable among men. Exposures independently associated with incident infection included a history of sex work (OR= 5.4, 95% CI: 1.5-18.7), concurrent syphilis infection (OR =4.1, 95% CI: 1.4-11.9), anal sex (OR = 3.0, 95% CI: 1.3-7.1), and having an HIV-positive sexual partner (OR= 1.4, 95% CI: 1.1-1.9). CONCLUSIONS: This study further demonstrates the public health utility of using the STARHS for the assessment of emerging trends in the HIV epidemic. Results from this study will help to target appropriate prevention strategies directed toward at-risk populations in Santos.     

Importance of sex partner HIV status in HIV risk assessment among men who have sex with men

Clinical HIV risk assessments have not typically integrated questions about sex partners' HIV status with questions about condom use and type of sex. Since 2001, we have asked all men who have sex with men (MSM) evaluated in an urban sexually transmitted disease (STD) clinic how often in the preceding 12 months they used condoms for anal sex with partners who were HIV-positive, HIV-negative, and of unknown HIV status. Overall, MSM displayed a pattern of assortative mixing by HIV status, particularly for unprotected anal intercourse (UAI). Nevertheless, 433 (27%) of 1580 MSM who denied knowing they were HIV-positive and 93 (43%) of 217 HIV-positive MSM reported having UAI with a partner of opposite or unknown HIV status. Among men who denied previously knowing they were HIV-positive, 24 (9.6%) of 251 MSM who reported having UAI with an HIV-positive partner or partner of unknown HIV status compared with 11 (1.7%) of 620 MSM who denied such exposure tested HIV-positive (odds ratio=5.8, 95% confidence interval: 2.8-12.1). UAI with an HIV-positive partner or partner with unknown HIV status was 69% sensitive and 73% specific in identifying men with previously undiagnosed HIV infection; UAI regardless of partner HIV status was 80% sensitive but only 45% specific. The positive predictive value was highest for risk assessments that included partner HIV status. Integrating questions about anal sex partner HIV status and condom use identifies MSM at greatest risk for HIV acquisition and transmission. These risk criteria might be effectively used to triage MSM into more intensive prevention interventions.     

Higher prevalence of anti-HCV antibodies among HIV-positive compared to HIV-negative inhabitants of Addis Ababa,Ethiopia

Serum samples (n = 4,593) collected in 1994 as part of a representative household community survey of the population of Addis Ababa who were 0-49 years old were tested for hepatitis C (HCV) antibodies. A third generation ELISA was used for primary screening and a line immunoblot assay for confirmation. HCV antibody prevalence was 0.9% (95% CI, 0.6-1.2%) and higher among HIV-positive compared to HIV-negative individuals (4.5% vs. 0.8%, respectively, P < 0.001). Similar higher prevalence of HCV antibodies was seen among HIV-positive compared to HIV-negative antenatal care attenders (2.9% vs. 0.8%, respectively, P = 0.003, n = 1,725), and sex workers (5.3% vs. 1.3%, respectively, P = 0.02, n = 383). Such association between HCV and HIV infection has not been described previously in Africa. After stratification by HIV status, HCV prevalence among women of the general population was identical to that of sex workers, suggesting that HCV sexual transmission is not common in this population and that HIV infection does not enhance susceptibility to HCV sexual transmission.     

High rate of recurrence of cervical intraepithelial neoplasia after surgery in HIV-positive women

OBJECTIVE: Our study investigated the rate of recurrence of cervical intraepithelial neoplasia (CIN) in HIV-positive women after surgery in the era of highly active antiretroviral therapy (HAART). METHODS: One hundred twenty-one HIV-positive women were followed-up with cytology, colposcopy, and histology after surgery for CIN. We conducted univariate and multivariate analyses to determine the relation between recurrence of CIN and risk factors using Cox proportional hazard models with left truncation. RESULTS: The rate of recurrence of any CIN was 22.3 per 100 patient-years and the rate of high-grade CIN was 8.6 per 100 patient-years during 166 and 279 patient-years of follow-up, respectively. In multivariate analysis, a positive margin was associated with a risk of recurrence of any CIN (relative risk [RR] = 3.5, 95% confidence interval [CI]: 1.2-9.8) and a risk of recurrence of high-grade CIN (RR = 9.0, 95% CI: 2.2-36.5). CD4 counts <200 cells/mm were associated with a risk of recurrence of any CIN (RR = 9.4, 95% CI: 2.7-32.7) but not with a risk of recurrence of high-grade CIN. HAART exhibited a protective effect on the recurrence of any CIN (RR = 0.3, 95% CI: 0.1-0.7) and of high-grade CIN (RR = 0.2, 95% CI: 0.1-0.7). CONCLUSION: CD4 cell counts <200/mm(3) and a positive margin were predictors of recurrence, whereas HAART had a strong protective effect. Although surgery is highly effective in immunocompetent patients, it seems to be effective only in preventing progression to cancer in HIV-infected women.     

Couples at risk: HIV-1 concordance and discordance among sexual partners receiving voluntary counseling and testing in Uganda

OBJECTIVE: To determine correlates of HIV-1 concordance for couples receiving voluntary HIV counseling and testing. DESIGN: Cross-sectional study of couples receiving voluntary HIV counseling and testing in Kampala, Uganda. METHODS: An interview and physical examination were conducted for 49 HIV-1-concordant (both partners infected with HIV) and 126 HIV-1-discordant (1 partner infected with HIV and 1 partner HIV negative) couples. Blood samples from all participants were tested for HIV-1 and syphilis serology. CD4 cell count and HIV load were characterized for all HIV-infected persons. Urine samples were tested for Neisseria gonorrhoeae and Chlamydia trachomatis using ligase chain reaction. Associations between couples' HIV status and key sociodemographic, behavioral, and biomedical factors were analyzed. RESULTS: Men in HIV-concordant couples were more likely than men in HIV-discordant couples to be living together with their sexual partner (odds ratio [OR], 11.3; 95% confidence interval [CI], 2.8-53.7; P=0.004), to be uncircumcised (OR, 4.5; 95% CI, 1.1-18.8; P=0.042), and to have higher HIV loads (OR for each log increase, 3.0; 95% CI, 2.0-4.7; P<0.001). Women in HIV-concordant couples were more likely than women in HIV-discordant couples to be living together with their sexual partner (OR, 19.0; 95% CI, 3.8-84.8), to have an uncircumcised male partner (OR, 6.5; 95% CI, 1.6-26.4), to have had a sexually transmitted disease in the 6 months before enrollment (OR, 1.9; 95% CI, 0.9-4.5), and to have higher HIV loads (OR for each log increase, 2.2; 95% CI, 1.5-3.2). CONCLUSIONS: Several behavioral and biologic risk factors were associated with HIV concordance for couples. Providing early sexually transmitted disease diagnosis and treatment, antiretroviral therapy, and specially designed counseling to HIV-discordant couples may help prevent HIV transmission in couples where being in a stable sexual relationship is a major risk factor for HIV infection.     

Web-based behavioral surveillance among men who have sex with men: a comparison of online and offline samples in London, UK

OBJECTIVE: To compare the characteristics of men who have sex with men (MSM) surveyed online (through gay Internet chat rooms and profiles) and offline (in community venues) in London, UK. METHODS: In February and March 2002, 879 MSM completed a self-administered pen-and-paper questionnaire distributed in central London gyms (offline sample). In May and June 2002, 1218 London MSM completed a self-administered questionnaire online, accessed through Internet chat rooms and profiles on gaydar and gay.com. RESULTS: Compared with men surveyed offline, those surveyed online were significantly less likely to only have sex with men (89 vs. 94%), to be in a relationship with a man (44 vs. 52%), or to have been tested for HIV (68 vs. 80%) (P < 0.001). Men recruited online were also younger (mean age, 34 vs. 36 years) and less likely to have had a higher education (67 vs. 79%) (P < 0.001). However, differences between online and offline samples were less pronounced for HIV-positive men and more pronounced for HIV-negative men and those who had never been tested for HIV. Regardless of HIV status, men recruited online were more likely to report high-risk sexual behavior (i.e., unprotected anal intercourse with a partner of unknown or discordant HIV status) than men surveyed offline (32 vs. 22%, P < 0.001). Men recruited online were also significantly more likely to have used the Internet to look for sex (85 vs. 45%, P < 0.001); for HIV-positive and negative men, seeking sex on the Internet was associated with high-risk sexual behavior (P < 0.01). In multivariate analysis, after controlling for confounding factors, being surveyed online was independently associated with high-risk sexual behavior for HIV-negative and never-tested men (HIV-negative men, adjusted odds ratio for online vs. offline samples, 1.73; 95% CI, 1.23, 2.42; P < 0.01; never-tested men adjusted odds ratio 2.45; 95% CI, 1.40, 4.29; P < 0.01). This was not the case for HIV-positive men (adjusted odds ratio for online vs. offline samples, 1.32; 95% CI, 0.69, 2.50; P = 0.4). CONCLUSION: The Internet offers valuable opportunities for conducting behavioral surveillance among MSM because it reaches some men who may not be easily accessed in the community yet who are at high risk for HIV and sexually transmitted diseases. Comparisons of the social, demographic, and behavioral characteristics of online and offline samples must, however, take into account the confounding effects of HIV status and seeking sex on the Internet.     

Continuing HIV transmission among injection drug users in Eastern Central Canada: the SurvUDI Study, 1995 to 2000

OBJECTIVE: To document HIV prevalence/incidence trends from 1995-2000 and associated risk factors among injection drug users (IDUs) in Eastern Central Canada as an indication of harm reduction strategy effectiveness. METHODS: Nonnominal cross-sectional data (one-time participants) and longitudinal data (repeat participants) were collected using convenience sampling. Participants provided informed consent for face-to-face interviews focused on injection drug use and sexual practices during the previous 6 months; oral fluid samples were taken for HIV testing by enzyme immunoassay. Unique encrypted codes for initially HIV-negative repeat participants permitted incidence rate calculations. RESULTS: In all, 6387 IDUs (median age, 31 years; range, 13-67; males, 73.5%) participated on 9724 occasions. HIV prevalence ranged from 4.7% (95% confidence interval [CI], 2.9-6.5) in semiurban areas to 20.1% (95% CI, 17.6-22.7) in Ottawa, Ontario. HIV incidence was 6.0 (95%CI, 4.5-7.6) per 100 person-years (py) in Montréal, Québec, 3.2 (95% CI, 2.2-4.2) per 100 py in Québec City and 7.0 (95% CI, 4.1-9.8) per 100 py in Ottawa/Hull. Reusing other IDUs' needles was reported by 38.4%. In multivariate logistic regression, IDUs injecting for 6 or more years were more likely to be HIV positive, particularly if cocaine was the predominant drug injected. Multivariate Cox regression revealed higher HIV incidence among those who predominantly injected cocaine, reused others' needles, had injected 6 years or more, injected with strangers, or were men reporting commercial sex work. CONCLUSIONS: These results reveal a volatile situation of continuing HIV transmission among IDUs in Eastern Central Canada.     

Incidence and epidemiology of anal cancer in the multicenter AIDS cohort study

OBJECTIVE: To examine the incidence and risk factors for anal cancer in a multicenter cohort of human immunodeficiency virus (HIV) positive and HIV-negative men who have sex with men followed between 1984 and 2006 (Multicenter AIDS Cohort Study). METHODS: Prospective analysis using Poisson regression and Cox proportional hazard models and a nested case-control study using conditional logistic regression. RESULTS: There were 28 cases of anal cancer among the 6,972 men who were evaluated. The incidence rate was significantly higher in HIV-positive men than in HIV-negative men (incidence rate = 69 vs 14 per 100,000 person-years). Among HIV-positive men, anal cancer incidence was higher in the highly active antiretroviral therapy (HAART) era than the pre-HAART era (incidence rate = 137 vs 30 per 100,000 person-years). In multivariate analysis restricted to the HAART era, anal cancer risk increased significantly with HIV infection (relative hazard = 4.7, 95% confidence interval = 1.3 to 17) and increasing number of unprotected receptive anal sex partners at the first 3 study visits (P trend = 0.03). Among HIV-positive men, current HAART use did not decrease anal cancer risk. CONCLUSIONS: HIV-positive men had increased risk of anal cancer. Improved survival of HIV-positive individuals after HAART initiation may allow for sufficient time for human papillomavirus-associated anal dysplasias to develop into malignancies, thus explaining the increased incidence of anal cancer in the HAART era.     

Decreased fertility among HIV-1-infected women attending antenatal clinics in three African cities

Population HIV prevalence estimates rely heavily on sentinel surveillance in antenatal clinics (ANCs), but because HIV reduces fertility, these estimates are biased. To aid interpretation of such data, we estimated HIV-associated fertility reduction among pregnant women in ANCs in Yaoundé (Cameroon), Kisumu (Kenya), and Ndola (Zambia). Data collection followed existing HIV sentinel surveillance procedures as far as possible. HIV prevalence among the women was 5.5% in Yaoundé, 30.6% in Kisumu, and 27.3% in Ndola. The birth interval was prolonged in HIV-positive multiparous women compared with HIV-negative multiparous women in all three sites: adjusted hazard ratios of pregnancy were 0.84 (95% confidence interval [CI]: 0.62-1.1) in Yaoundé, 0.82 (95% CI: 0.70-0.96) in Kisumu, and 0.74 (95% CI: 0.61-0.90) in Ndola, implying estimated reductions in the risk of pregnancy in HIV-positive women of between 16% and 26%. For primiparous women, the interval between sexual debut and birth was longer in HIV-positive women than in HIV-negative women in all sites, although the association was lost in Ndola after adjusting for age and other factors. Consistent results in different study sites help in the development of standard methods for improving ANC-based surveillance estimates of HIV prevalence. These may be easier to devise for multiparous women than for primiparous women.     

HIV incidence among repeat HIV testers at a county hospital, San Francisco, California, USA

OBJECTIVES: To estimate HIV incidence, characterize correlates of HIV seroconversion, and monitor temporal trends in HIV transmission among patients repeatedly tested for HIV by a county hospital in San Francisco. DESIGN: Retrospective longitudinal study. METHODS: HIV incidence was retrospectively calculated among persons voluntarily tested for HIV antibody more than once at San Francisco's county hospital or one of its affiliated satellite community clinics between 1993 and 1999. Linkage of HIV test results in computerized databases identified "seroconverters" as individuals who had a negative antibody test followed by a positive test. The interval between tests was used as the person-time at risk. Cox proportional hazards analysis identified correlates of HIV seroconversion. RESULTS: A total of 84 HIV seroconversions were identified among 2893 eligible patients repeatedly tested for HIV antibody over a cumulative 5860 person-years (PYs) (incidence of 1.4 per 100 PYs, 95% confidence interval [CI]: 1.2-1.7). The majority of seroconversions (71 [84.5%]) were among injection drug users (IDUs) (incidence of 2.0 per 100 PYs, CI: 1.6-2.4). HIV incidence was highest among men who have sex with men (MSM) who were also IDUs (incidence of 3.8 per 100 PYs, CI: 2.7-5.1) and lowest among non-IDUs, heterosexual men, and non-IDU women (incidence of 0.3 per 100 PYs, CI: 0.1-0.6). In multivariate analysis, correlates of HIV seroconversion were age 25 to 29 years (hazard ratio [HR] = 3.9, CI: 2.4-6.3), MSM (HR = 2.9, CI: 1.9-4.4), and IDU (HR = 3.2, CI: 1.8-5.8). Overall, no temporal trend in annual HIV incidence was noted during the study period; however, HIV incidence among MSM IDUs increased from 2.9 per 100 PYs in 1996 to 4.7 per 100 PYs in 1998. CONCLUSIONS: The rate of seroconversion in this hospital and affiliated clinic population is unexpectedly high. Moreover, HIV transmission among IDU patients has not decreased over the last several years. The San Francisco county hospital provides a high-risk sentinel population to monitor emerging trends in HIV transmission, especially among IDUs, and presents multiple opportunities for prevention interventions, because these patients are being seen repeatedly by clinicians.     

Want children? Cum clean

Researchers are cautiously optimistic that HIV-positive men with undetectable viral loads may be able to have children with HIV-negative women, without infecting either their partner or their baby. A Spanish study showed that 70 percent of the people transmitting the virus had viral loads greater than 15,000 copies. Unprotected sex among serodiscordant couples is still not recommended, as HIV is found in cells other than semen. Antiviral therapy in U.S. women has also been found to decrease HIV viral load in vaginal secretions, but there is not enough evidence to say whether it is safe for those women to become pregnant.