Schistosoma mansoni and HIV acquisition in fishing communities of Lake Victoria, Uganda: a nested case-control study.

OBJECTIVE: It has been suggested that Schistosoma mansoni, which is endemic in African fishing communities, might increase susceptibility to human immunodeficiency virus (HIV) acquisition. If confirmed, this would be of great public health importance in these high HIV-risk communities. This study was undertaken to determine whether S. mansoni infection is a risk factor for HIV infection among the fishing communities of Lake Victoria, Uganda. We conducted a matched case-control study, nested within a prospective HIV incidence cohort, including 50 HIV seroconverters (cases) and 150 controls during 2009-2011. METHODS: S. mansoni infection prior to HIV seroconversion was determined by measuring serum circulating anodic antigen (CAA) in stored serum. HIV testing was carried out using the Determine rapid test and infection confirmed by enzyme-linked immunosorbent assays. RESULTS: About 49% of cases and 52% of controls had S. mansoni infection prior to HIV seroconversion (or at the time of a similar study visit, for controls): odds ratio, adjusting for ethnicity, religion, marital status, education, occupation, frequency of alcohol consumption in previous 3 months, number of sexual partners while drunk, duration of stay in the community, and history of schistosomiasis treatment in the past 2 years was 1.23 (95% CI 0.3-5.7) P = 0.79. S. mansoni infections were chronic (with little change in status between enrolment and HIV seroconversion), and there was no difference in median CAA concentration between cases and controls. CONCLUSIONS: These results do not support the hypothesis that S. mansoni infection promotes HIV acquisition.

Association between Mycoplasma genitalium infection and HIV acquisition among female sex workers in Uganda: evidence from a nested case-control study.

OBJECTIVES: Cross-sectional studies have shown a strong association between Mycoplasma genitalium and HIV infections. We previously reported that in a cohort of female sex workers in Uganda, M genitalium infection at baseline was associated with HIV seroconversion. Here we examine the temporal association between the M genitalium infection status shortly before HIV seroconversion and HIV acquisition. METHODS: A nested case-control study was conducted within a cohort of women at high risk for HIV in Kampala. Cases were those of women acquiring HIV within 2 years of enrolment. For each of the 42 cases, 3 controls were selected from women HIV negative at the visit when the corresponding case first tested HIV seropositive. The association between HIV acquisition and M genitalium infection immediately prior to HIV testing was analysed using conditional logistic regression. RESULTS: There was weak evidence of an association between M genitalium infection and HIV acquisition overall (crude OR=1.57; 95% CI 0.67 to 3.72, aOR=2.28: 95% CI 0.81 to 6.47). However, time of M genitalium testing affected the association (p value for effect-modification=0.004). For 29 case-control sets with endocervical samples tested 3 months prior to the first HIV-positive result, M genitalium infection increased the risk of HIV acquisition (crude OR=3.09; 95% CI 1.06 to 9.05, aOR=7.19; 95% CI 1.68 to 30.77), whereas there was little evidence of an association among the 13 case-control sets with samples tested at an earlier visit (crude OR=0.30: 95% CI 0.04 to 2.51; aOR=0.34; 95% CI 0.02 to 5.94). CONCLUSIONS: Our study showed evidence of a temporal relationship between M genitalium infection and HIV acquisition that suggests that M genitalium infection may be a co-factor in the acquisition of HIV infection.

Natural history of Mycoplasma genitalium infection in a cohort of female sex workers in Kampala, Uganda.

BACKGROUND: There have been few studies of the natural history of Mycoplasma genitalium in women. We investigated patterns of clearance and recurrence of untreated M. genitalium infection in a cohort of female sex workers in Uganda. METHODS: Women diagnosed as having M. genitalium infection at enrollment were retested for the infection at 3-month intervals. Clearance of infection was defined as testing negative after having a previous positive result: persistence was defined as testing positive after a preceding positive test result, and recurrence as testing positive after a preceding negative test result. Adjusted hazard ratios for M. genitalium clearance were estimated using Cox proportional hazards regression. RESULTS: Among 119 participants infected with M. genitalium at enrollment (prevalence, 14%), 55% had spontaneously cleared the infection within 3 months; 83%, within 6; and 93%, within 12 months. The overall clearance rate was 25.7/100 person-years (pyr; 95% confidence interval, 21.4-31.0). HIV-positive women cleared M. genitalium infection more slowly than did HIV-negative women (20.6/100 pyr vs. 31.3/100 pyr, P = 0.03). The clearance rate was slower among HIV-positive women with CD4 counts less than 350/mL than among those with higher CD4 counts (9.88/100 pyr vs. 29.5/100 pyr, P <; 0.001). After clearing the infection, M. genitalium infection recurred in 39% women. CONCLUSIONS: M. genitalium is likely to persist and recur in the female genital tract. Because of the urogenital tract morbidity caused by the infection and the observed association with HIV acquisition, further research is needed to define screening modalities, especially in populations at high risk for HIV, and to optimize effective and affordable treatment options.

Prevalence and correlates of Mycoplasma genitalium infection among female sex workers in Kampala, Uganda.

BACKGROUND: The importance of Mycoplasma genitalium in human immunodeficiency virus (HIV)-burdened sub-Saharan Africa is relatively unknown. We assessed the prevalence and explored determinants of this emerging sexually transmitted infection (STI) in high-risk women in Uganda. METHODS: Endocervical swabs from 1025 female sex workers in Kampala were tested for Mycoplasma genitalium using a commercial Real-TM polymerase chain reaction assay. Factors associated with prevalent Mycoplasma genitalium, including sociodemographics, reproductive history, risk behavior, and HIV and other STIs, were examined using multivariable logistic regression. RESULTS: The prevalence of Mycoplasma genitalium was 14% and higher in HIV-positive women than in HIV-negative women (adjusted odds ratio [OR], 1.64; 95% confidence interval [CI], 1.12-2.41). Mycoplasma genitalium infection was less prevalent in older women (adjusted OR, 0.61; 95% CI, .41-.90 for women ages 25-34 years vs <25 years; adjusted OR, 0.32; 95% CI, .15-.71 for women ≥ 35 years vs those <25 years) and in those who had been pregnant but never had a live birth (adjusted OR, 2.25; 95% CI, 1.04-4.88). Mycoplasma genitalium was associated with Neisseria gonorrhoeae (adjusted OR, 1.84; 95% CI, 1.13-2.98) and with Candida infection (adjusted OR, 0.41; 95% CI, .18-.91), and there was some evidence of association with Trichomonas vaginalis (adjusted OR, 1.56; 95% CI, 1.00-2.44). CONCLUSIONS: The relatively high prevalence of Mycoplasma genitalium and its association with prevalent HIV urgently calls for further research to explore the potential role this emerging STI plays in the acquisition and transmission of HIV infection.

Effect of pregnancy on immunological and virological outcomes of women on ART: a prospective cohort study in rural Uganda, 2004-2009.

OBJECTIVES: Before antiretroviral therapy (ART) introduction, pregnancy was associated with a sustained drop in CD4 cell count in HIV-infected women. We examined the effects of pregnancy on immunological and virological ART outcomes. METHODS: Between January 2004 and March 2009, we studied HIV-infected women receiving ART in a prospective open cohort study in rural Uganda. We used random effects regression models to compare the CD4 counts of women who became pregnant and those who did not, and among the pregnant women before and after pregnancy. CD4 count and proportions with detectable viral load (≥400 copies/ml) were compared between the two groups using the Mann-Whitney rank sum test and logistic regression respectively. RESULTS: Of 88 women aged 20-40 years receiving ART, 23 became pregnant. At ART initiation, there were no significant differences between those who became pregnant and those who did not in clinical, immunological and virological parameters. Among women who became pregnant, CD4 cell count increased before pregnancy (average 75.9 cells/mm(3) per year), declined during pregnancy (average 106.0) but rose again in the first year after delivery (average 88.6). Among women who did not become pregnant, the average CD4 cell count rise per year for the first 3 years was 88.5. There was no significant difference in the proportions of women with detectable viral load at last clinic visit among those who became pregnant (8.7%) and those who did not (16.1%), P = 0.499. CONCLUSION: Pregnancy had no lasting effect on the immunological and virological outcomes of HIV-infected women on ART.

Alcohol use, mycoplasma genitalium, and other STIs associated With HIV incidence among women at high risk in Kampala, Uganda.

BACKGROUND: In 2008, the first clinic for women involved in high-risk sexual behavior was established in Kampala, offering targeted HIV prevention. This article describes rates, determinants, and trends of HIV incidence over 3 years. METHODS: A total of 1027 women at high risk were enrolled into a closed cohort. At 3-monthly visits, data were collected on sociodemographic variables and risk behavior; biological samples were tested for HIV and other reproductive tract infections/sexually transmitted infections (RTI/STIs). Hazard ratios for HIV incidence were estimated using Cox proportional hazards regression among the 646 women HIV negative at enrolment. RESULTS: HIV incidence was 3.66/100 person-years (pyr) and declined from 6.80/100 pyr in the first calendar year to 2.24/100 pyr and 2.53/100 pyr in the following years (P trend = 0.003). Sociodemographic and behavioral factors independently associated with HIV incidence were younger age, younger age at first sex, alcohol use (including frequency of use and binge drinking), number of paying clients in the past month, inconsistent condom use with clients, and not being pregnant. HIV incidence was also independently associated with Mycoplasma genitalium infection at enrolment [adjusted hazard ratio (aHR) = 2.28, 95% confidence interval (CI): 1.15 to 4.52] and with Neisseria gonorrhoeae (aHR = 5.91, 95% CI: 3.04 to 11.49) and Trichomonas vaginalis infections at the most recent visit (aHR = 2.72, 95% CI: 1.27 to 5.84). The population attributable fractions of HIV incidence for alcohol use was 63.5% (95% CI: 6.5 to 85.8) and for treatable RTI/STIs was 70.0% (95% CI: 18.8 to 87.5). CONCLUSIONS: Alcohol use and STIs remain important risk factors for HIV acquisition, which call for more intensive control measures in women at high risk. Further longitudinal studies are needed to confirm the association between M. genitalium and HIV acquisition.