Various Types of HIV Mixed Infections in Cameroon

AbstractIn order to assess the incidence of HIV mixed infection as well as to clarify the molecular epidemiology of HIV in central Africa, we investigated 43 HIVs obtained from 211 Cameroonian AC, ARC, and AIDS patients in 1994 and 1995. Part of thepolregion and part of theenvregion were phylogenetically analyzed. The genotypes observed were varied: of 43 specimens, 28 (65%) were subtype A, 1 (2%) was subtype B, 2 (5%) were subtype D, 3 (7%) were subtype F, and 2 (5%) were group O. Of the remaining 7 specimens, 3 were mixed infections with HIV-1 subtypes A and C, HIV-1 subtypes C and F, and HIV-2 subtype A and HIV-1 subtype A; 1 was a mixed infection with HIV-1 subtypes A and D and the highly divergent group O (triple infection); another 3 appeared to consist of mosaic genomes (A/G, A/E, and B/A recombinant). These data show that various types of mixed infection, such as between different subtypes of HIV-1 group M, between HIV-1 and HIV-2, and even between HIV-1 groups O and M, were confirmed at a rather high frequency (approximately 10%). The mixed infection is particularly significant where there is a greater variety of HIV-1 subtypes circulating, since it results in new genetic diversity generated by intersubtype recombination

Antiretroviral Drug Resistance and Routine Therapy, Cameroon

Among 128 patients routinely receiving highly active antiretroviral therapy in an HIV/AIDS outpatient clinic in Cameroon, 16.4% had drug resistance after a median of 10 months. Of these, 12.5% had resistance to nucleoside reverse transcriptase inhibitors (NRTIs), 10.2% to non-NRTIs, and 2.3% to protease inhibitors

Field assessment of generic antiretroviral drugs : a prospective cohort study in Cameroon

Objective: To assess the effectiveness of generic anti-retroviral drugs in terms of survival and virological and immunological responses, as well as their tolerability and the emergence of viral resistance. Methods: A total of 109 HIV-1-infected patients were enrolled in a prospective cohort study in Yaoundé, Cameroon. Available generic drugs were a fixed-dose combination (FDC) of zidovudine (ZDV) and lamivudine (3TC), an FDC of 3TC, stavudine (d4T) and nevirapine (NVP), and individual formulations of ZDV, 3TC and NVP. Results: At baseline, the median CD4 cell count was 150/mm3 [interquartile range (IQR) 61-223] and median viral load was 5.4 log10 copies/ml (IQR 4.8-5.6); 78% of patients received ZDV/3TC/NVP and 22% received 3TC/d4T/NVP. Median follow-up was 16 months (IQR 11-23). The survival probability was high (0.92 at 12 months); plasma viral load declined by a median of 3.3 log10 copies/ml and 86.9% of the intention-to-treat population had viral load &lt;400 copies/ml at 12 months; CD4 count had increased by a median of 106 cells/mm3 at 12 months; drug resistance rarely emerged (incidence rate 3.2 per 100 person-years); and the treatments were reasonably well-tolerated (incidence rate of severe adverse effects 7.8 per 100 person-years). Conclusion: Together with previous pharmacological and clinical studies, this prospective study suggests that these generic antiretroviral drugs can be used in developing countries.</p

Effectiveness and safety of a generic fixed-dose combination of nevirapine, stavudine, and lamivudine in HIV-1-infected adults in Cameroon: open-label multicentre trial

Background: Generic fixed-dose combinations have been prequalified by WHO to treat HIV-infected patients in resource-limited countries. Despite their widespread use they are, however, not yet recommended by some of the major donor agencies owing to scarcity of clinical data on effectiveness, safety, and quality. We aimed to assess these issues for one of the most frequently prescribed treatments in Africa, a generic fixed-dose combination of nevirapine, stavudine, and lamivudine. Methods: 60 patients were followed in an open-label, 24-week multicentre trial in Cameroon. All patients received one tablet of the fixed-dose combination drug twice daily. The primary outcome measure was the proportion of patients with viral load less than 400 copies per mL at the end of the study period, in an intention-to-treat analysis. Findings: At baseline, 92% of patients (n=55) had AIDS; median CD4 count was 118 cells per microL (IQR 78-167) and median plasma HIV-1 RNA was 104?736 copies per mL (40804-243787). The proportion of patients with undetectable viral load (&lt;400 copies per mL) after 24 weeks of treatment was 80% (95% CI 68-89). Median (IQR) change in viral load was -3.1 log10 copies per mL (-2.5 to -3.6) and in CD4 count 83 cells per microL (40-178). The probability of remaining alive or free of new AIDS-defining events was 0.85 (95% CI 0.73-0.92). Frequency of disease progression was 32.0 (95% CI 16.6-61.5), severe adverse effects 17.8 (7.4-42.7), and genotypic resistance mutations 7.1 (1.8-28.4) per 100 person-years. Mean reported adherence rate was 99%. Median drug concentrations in tablets were 96% of expected values for nevirapine, 89% for stavudine, and 99% for lamivudine. Interpretation: Our findings lend support to use and funding of a generic fixed-dose combination of nevirapine, stavudine, and lamivudine as first-line antiretroviral treatment in developing countries.</p

Simplified Strategy for Detection of Recombinant Human Immunodeficiency Virus Type 1 Group M Isolates by gag/env Heteroduplex Mobility Assay

We developed a heteroduplex mobility assay in the gag gene (gag HMA) for the identification of group M subtypes A to H. The assay covers the region coding for amino acid 132 of p24 to amino acid 20 of p7 (according to human immunodeficiency virus type 1 [HIV-1] ELI, 460 bp). The gag HMA was compared with sequencing and phylogenetic analysis of an evaluation panel of 79 HIV-1 group M isolates isolated from infected individuals from different geographic regions. Application of gag HMA in combination with env HMA on 252 HIV-1- positive plasma samples from Bénin, Cameroon, Kenya, and Zambia revealed a high prevalence of a variety of intersubtype recombinants in Yaoundé, Cameroon (53.8%); Kisumu, Kenya (26.8%); and Cotonou, Bénin (41%); no recombinants were identified among the samples from Ndola, Zambia. The AG(IbNG) circulating recombinant form, as determined by gag HMA, was found to be the most common intersubtype recombinant in Yaoundé (39.4%) and Cotonou (38.5%). Using a one-tube reverse transcriptase PCR protocol, this gag HMA in combination with env HMA is a useful tool for rapidly monitoring the prevalence of the various genetic subtypes as well as of recombinants of HIV-1. Moreover, this technology can easily be applied in laboratories in developing countries