Molecular epidemiology of dual HIV-1/HIV-2 seropositive adults from Senegal, West Africa.

Dual infection with HIV-1 and HIV-2 can occur in locales where these viruses co-circulate, most commonly in West Africa. Although dual seropositivity is common in this region, the true rate of dual infection remains unclear. In addition, whether unique HIV-1 subtypes are circulating in dually infected individuals is unknown. A cohort of 47 HIV-1 and HIV-2 dually seropositive individuals from Senegal, West Africa was screened for the presence of HIV-1 and HIV-2 gag and env PBMC viral DNA sequences using PCR. Of the 47 dual HIV-1/HIV-2 seropositive individuals tested, 19 (40.4%) had infection with both HIV-1 and HIV-2 confirmed by genetic sequence analysis, whereas only HIV-1 or HIV-2 was confirmed in 17 (36.2%) or 9 (19.1%), respectively. The majority of HIV-1 subtypes found were CRF-02 and A, although subtypes D, C, G, J and B were also found, reflecting the subtypes known to be circulating in Senegal. There was no significant difference in HIV-1 subtype distribution between individuals with confirmed dual infection and patients in this study with dual seropositivity but lacking HIV-2, or with HIV-1 infected patients within the general population in Senegal, although the study was underpowered to detect anything but large differences. The prevalence of HIV-1/HIV-2 dual infection appears to be significantly less than that of dually seropositive individuals and this likely reflects cross-reactive serology. The common HIV-1 subtypes prevalent in West Africa (CRF-02 and subtype A) have a similar distribution to those found in our cohort of dually infected and dually seropositive subjects.

Characteristics and presenting complaints of outpatients with undiagnosed HIV infection: potential utility in selecting subjects for HIV testing.

HIV testing of individuals presenting to outpatient medical clinics has generally been based upon a selection system, with testing limited to those having signs or symptoms previously found associated with HIV-1 infection among hospitalized patients. However, little is known about the efficacy of this approach, particularly in Africa. Among patients presenting to a large outpatient infectious disease clinic in Dakar, Senegal, the utility of using specific demographic and behavioral characteristics and individual presenting complaints to identify individuals with previously undiagnosed HIV-1 or HIV-2 infection was examined. Using a simple statistical approach, a composite screening rule was estimated to identify subjects with the highest probability of testing HIV positive, ie, patients who would most benefit from HIV testing. Using the presenting complaint allows identification of 83% of HIV-infected women by testing only 35% of women presenting to the clinic. Similarly, using the presenting complaint and various demographic and behavioral characteristics, it was possible to identify 84% of HIV-infected men by screening 40% of men presenting to the clinic. This study suggests that this method might provide a cost-effective approach that permits limited screening resources to be spent in a way that maximizes individual and societal benefit.

Increased risk of high-grade cervical squamous intraepithelial lesions and invasive cervical cancer among African women with human immunodeficiency virus type 1 and 2 infections.

To assess the risk of prevalent high-grade cervical squamous intraepithelial lesions (HSILs) or invasive cervical cancer (ICC) associated with human immunodeficiency virus (HIV) type 1, HIV-2, and human papillomavirus (HPV) infections, HIV load, and CD4 cell count, we studied 4119 women attending an outpatient clinic in Senegal. HIV infection was associated with increased rates of cervical infection with high-risk HPVs. Among women infected with high-risk HPVs, those with HIV-1 (odds ratio [OR], 2.2; 95% confidence interval [CI], 1.0-4.8), HIV-2 (OR, 6.0; 95% CI, 2.1-17.1), or dual HIV infection (OR, 8.0; 95% CI, 2.0-31.5) were more likely to have HSILs or ICC diagnosed than were HIV-negative women; this association was not observed among women not infected with high-risk HPVs. Among women with HIV, higher HIV plasma RNA loads and lower CD4 cell counts were associated with high-risk HPV infection and degree of cervical abnormality. Furthermore, HIV-2-positive women were more likely to have HSILs (OR, 3.3; 95% CI, 0.9-12.4) or ICC (OR, 7.9; 95% CI, 1.1-57) than were HIV-1-positive women.

Equal plasma viral loads predict a similar rate of CD4+ T cell decline in human immunodeficiency virus (HIV) type 1- and HIV-2-infected individuals from Senegal, West Africa.

Human immunodeficiency virus (HIV) type 2 infection is characterized by slower disease progression to acquired immunodeficiency syndrome than results from HIV-1 infection. To better understand the biological factors underlying the different natural histories of infection with these 2 retroviruses, we examined the relationship between HIV RNA and DNA levels and the rate of CD4(+) T cell decline among 472 HIV-1- and 114 HIV-2-infected individuals from Senegal. The annual rate of CD4(+) T cell decline in the HIV-2 cohort was approximately one-fourth that seen in the HIV-1 cohort. However, when the analysis was adjusted for baseline plasma HIV RNA level, the rates of CD4(+) T cell decline per year for the HIV-1 and HIV-2 cohorts were similar (a rate increase of approximately 4% per year for each increase in viral load of 1 log(10) copies/mL). Therefore, plasma HIV load is predictive of the rate of CD4(+) T cell decline over time, and the correlation between viral load and the rate of decline appears to be similar among all HIV-infected individuals, regardless of whether they harbor HIV-1 or HIV-2.