Reduced and highly diverse peripheral HIV-1 reservoir in virally suppressed patients infected with non-B HIV-1 strains in Uganda.

BACKGROUND: Our understanding of the peripheral human immunodeficiency virus type 1 (HIV-1) reservoir is strongly biased towards subtype B HIV-1 strains, with only limited information available from patients infected with non-B HIV-1 subtypes, which are the predominant viruses seen in low- and middle-income countries (LMIC) in Africa and Asia. RESULTS: In this study, blood samples were obtained from well-suppressed ART-experienced HIV-1 patients monitored in Uganda (n = 62) or the U.S. (n = 50), with plasma HIV-1 loads < 50 copies/ml and CD4+ T-cell counts > 300 cells/ml. The peripheral HIV-1 reservoir, i.e., cell-associated HIV-1 RNA and proviral DNA, was characterized using our novel deep sequencing-based EDITS assay. Ugandan patients were slightly younger (median age 43 vs 49 years) and had slightly lower CD4+ counts (508 vs 772 cells/ml) than U.S. individuals. All Ugandan patients were infected with non-B HIV-1 subtypes (31% A1, 64% D, or 5% C), while all U.S. individuals were infected with subtype B viruses. Unexpectedly, we observed a significantly larger peripheral inducible HIV-1 reservoir in U.S. patients compared to Ugandan individuals (48 vs. 11 cell equivalents/million cells, p < 0.0001). This divergence in reservoir size was verified measuring proviral DNA (206 vs. 88 cell equivalents/million cells, p < 0.0001). However, the peripheral HIV-1 reservoir was more diverse in Ugandan than in U.S. individuals (8.6 vs. 4.7 p-distance, p < 0.0001). CONCLUSIONS: The smaller, but more diverse, peripheral HIV-1 reservoir in Ugandan patients might be associated with viral (e.g., non-B subtype with higher cytopathicity) and/or host (e.g., higher incidence of co-infections or co-morbidities leading to less clonal expansion) factors. This highlights the need to understand reservoir dynamics in diverse populations as part of ongoing efforts to find a functional cure for HIV-1 infection in LMICs.

Higher sequence diversity in the vaginal tract than in blood at early HIV-1 infection.

In the majority of cases, human immunodeficiency virus type 1 (HIV-1) infection is transmitted through sexual intercourse. A single founder virus in the blood of the newly infected donor emerges from a genetic bottleneck, while in rarer instances multiple viruses are responsible for systemic infection. We sought to characterize the sequence diversity at early infection, between two distinct anatomical sites; the female reproductive tract vs. systemic compartment. We recruited 72 women from Uganda and Zimbabwe within seven months of HIV-1 infection. Using next generation deep sequencing, we analyzed the total genetic diversity within the C2-V3-C3 envelope region of HIV-1 isolated from the female genital tract at early infection and compared this to the diversity of HIV-1 in plasma. We then compared intra-patient viral diversity in matched cervical and blood samples with three or seven months post infection. Genetic analysis of the C2-V3-C3 region of HIV-1 env revealed that early HIV-1 isolates within blood displayed a more homogeneous genotype (mean 1.67 clones, range 1-5 clones) than clones in the female genital tract (mean 5.7 clones, range 3-10 clones) (p<0.0001). The higher env diversity observed within the genital tract compared to plasma was independent of HIV-1 subtype (A, C and D). Our analysis of early mucosal infections in women revealed high HIV-1 diversity in the vaginal tract but few transmitted clones in the blood. These novel in vivo finding suggest a possible mucosal sieve effect, leading to the establishment of a homogenous systemic infection.

Infecting HIV-1 Subtype Predicts Disease Progression in Women of Sub-Saharan Africa.

INTRODUCTION: Long-term natural history cohorts of HIV-1 in the absence of treatment provide the best measure of virulence by different viral subtypes. METHODS: Newly HIV infected Ugandan and Zimbabwean women (N=303) were recruited and monitored for clinical, social, behavioral, immunological and viral parameters for 3 to 9.5years. RESULTS: Ugandan and Zimbabwean women infected with HIV-1 subtype C had 2.5-fold slower rates of CD4 T-cell declines and higher frequencies of long-term non-progression than those infected with subtype A or D (GEE model, P<0.001), a difference not associated with any other clinical parameters. Relative replicative fitness and entry efficiency of HIV-1 variants directly correlated with virulence in the patients, subtype D>A>C (P<0.001, ANOVA). DISCUSSION: HIV-1 subtype C was less virulent than either A or D in humans; the latter being the most virulent. Longer periods of asymptomatic HIV-1 subtype C could explain the continued expansion and dominance of subtype C in the global epidemic.

Hormonal contraceptive use and discontinuation among HIV-infected women in Uganda and Zimbabwe.

BACKGROUND: Hormonal contraception (HC) use by HIV-infected women has been identified by the World Health Organization as an important strategy for reducing vertical HIV transmission. Little is known about the factors associated with HC discontinuation among HIV-infected women. METHODS: We analyzed data from a prospective study of HC use among 231 HIV-infected users with oral contraceptive (OC) or injectable depot medroxyprogesterone acetate (DMPA) in Uganda and Zimbabwe. We used Kaplan-Meier survival curves to estimate the median duration of OC and DMPA use and use of any highly effective contraceptive method. Cox proportional hazards models were used to investigate factors associated with HC discontinuation. RESULTS: Median duration was 36 months [95% confidence interval (CI): 14 to 61] for OC use and 19 months (95% CI: 14 to 24) for DMPA use. Median duration of any highly effective method was 36 months (95% CI: 26 to N/A) for OC users and 22 months (95% CI: 14 to 38) for DMPA users. In multivariable analyses, living in Zimbabwe [hazard ratio (HR): 0.39; 95% CI: 0.18 to 0.83], no partner (HR: 7.18; 95% CI: 3.05 to 16.88), and cervical infection (HR: 1.99; 95% CI: 0.90 to 4.41) were associated with OC discontinuation. No partner (HR: 2.00; 95% CI: 1.12 to 3.58), nausea (HR: 1.84; 95% CI: 1.02 to 3.34), and excessive night sweats (HR: 1.80; 95% CI: 0.95 to 3.40) were associated with DMPA discontinuation. CONCLUSION: Long-term use of HC methods is acceptable to HIV-infected women. Women discontinue for a variety of reasons, primarily unrelated to HIV. Alternative methods and ongoing contraceptive counseling is essential to reduce unplanned pregnancies and vertical HIV transmission.

Oropharyngeal colonization by Streptococcus pneumoniae among HIV-infected adults in Uganda: assessing prevalence and antimicrobial susceptibility.

OBJECTIVES: To evaluate characteristics of Streptococcus pneumoniae associated with oropharyngeal colonization in the Ugandan adult HIV population. METHODS: We conducted a cross-sectional study at the outpatient HIV clinic at the Joint Clinical Research Centre in Kampala, Uganda between July 2004 and February 2005. Six hundred HIV-infected individuals were interviewed and had oropharyngeal specimens collected. Pneumococci were isolated from these specimens and antimicrobial susceptibility patterns determined using standard microdilution methods. Serotypes of the pneumococcal isolates were evaluated by capsular swelling reaction with commercial antisera. RESULTS: The prevalence of oropharyngeal colonization with pneumococci was 18% (108/600). Thirty-two different pneumococcal serotypes were identified, and the most common were serotypes 3 (14.7%), 19F (6.4%), 23F (6.4%), and 16 (5.5%). Seventy-two percent of the isolates were penicillin (PCN) intermediate (MICs 0.12-1 microg/mL), the remainder all being PCN susceptible, and >99% were trimethoprim-sulfamethoxazole (TMP-SMX) resistant. Novel PCN intermediate serotypes included 7, 11, 16, 20, 22, 24, and 34. Only one isolate was resistant to macrolides, and resistance to other antibiotics was rare. CONCLUSIONS: HIV-infected adults in Uganda are colonized with pneumococci that exhibit a high degree of TMP-SMX and PCN non-susceptibility, with several unique PCN non-susceptible serotypes that are not included in current vaccine preparations.