Serologic testing algorithm for recent HIV seroconversion in estimating incidence of HIV-1 among adults visiting a VCT centre at a Kenyan tertiary health institution

Objective: To determine HIV high risk groups among adults visiting Kenyatta National Hospital Voluntary Counselling and Testing Centre by use of Serologic Testing Algorithm for Recent HIV Seroconversion (STARHS).Design: A cross-sectional study of adults.Setting: Kenyatta National Hospital Voluntary and Counselling Centre.Results: Of the 6,415 adults screened for antibodies to HIV at Kenyatta National Hospital VCT Centre between July 2002 and February 2003, 728 tested positive in the two HIV screening tests used at the center, indicating a prevalence of 11%. Of these seropositive cases, 355 consented to participate in the study. Using STARHS, 34 (9.6%) of the plasma samples were classified as being from individuals with recent infection (within 170 days), giving an annual estimated HIV-1 incidence in this population of 1.3 infections per 100 person-years with a 95% CI of 0.872–1.728%. Young adults had a higher rate of new infection than older adults. Young females were infected much earlier in life, with a peak age of new infections of 26 years, versus. 31 years for young males.Conclusion: This study confirms our hypothesis that STARHS or Detuned assay can be used to determine HIV incidence in this population. The HIV high risk groups as identified by this study are young women between ages 16 to 26 years old and men between ages 45 to 55 years of age

Partner notification in the management of sexually transmitted infections in Nairobi, Kenya

Objective: To assess utilization of partner notification as a tool in prevention and control of Sexually transmitted infections in Nairobi City Council clinics. Design: A cross-sectional study carried out between April and September 2000. Setting: Nairobi City Council health clinics were stratified into eight administrative divisions and a total of 16 out of 54 primary health clinics with at least four STIs patients per day were selected. A standard questionnaire was administered to every fourth patient with clinical diagnosis of STIs who gave consent on exist. Sexual partners referred by index cases during the five day period from each clinic were also enrolled into the study. An additional questionnaire was administered to HCP who were managing STIs patients and their sex partners. Results: Of 407 STIs patients recruited between April and September 2000, 20.6% were primary and 2% were secondary referrals giving an average referral rate of 23%. Respondents with multiple sex partners were less likely to refer their partners compared to those who had one partner (17.9% vs 82.1%,

Identification of a novel HLA B*57 restricted cytotoxic T-lymphocyte epitope within HIV-1 rev.

HLA-B5701 and its related allele B5703 have been shown to be strongly associated with slow HIV-1 disease progression. To elucidate the effect of these alleles fully on disease progression it is essential to identify key HIV-1 epitopes that are restricted by these alleles. Here we describe the identification of a novel HLA-B5701, B5703 restricted epitope within HIV-1 rev, which accounted for up to 25 and 40% of the total cytotoxic T-lymphocyte responses in two patients

Quantitative ex vivo analysis of functional virus-specific CD8 T lymphocytes in the blood and genital tract of HIV-infected women.

BACKGROUND: CD8 T lymphocytes are important in HIV-1 control and mediate virus-specific immunity in the blood and genital tract. The induction and monitoring of mucosal CD8 cell responses will be an important component of HIV-1 vaccine trials, but information regarding the frequency, phenotype and function of genital tract CD8 cell responses is lacking. METHODS: Simultaneous blood and cervical cytobrush samples were obtained from 16 HIV-1-infected Kenyan sex workers. Epitope-specific CD8 T lymphocyte frequencies in the blood and genital tract were analysed after short-term peptide incubation and intracellular cytokine staining for interferon-gamma (IFN gamma). RESULTS: Cervical sampling resulted in adequate cell numbers for analysis in 10/16 women. Background IFN gamma production was higher in CD3+/CD8+ lymphocytes from the genital tract than from blood (0.48% versus 0.1%; P < 0.01). Responses to staphylococcal enterotoxin B were detected in cervical CD8 lymphocytes from 10/10 women, at a similar frequency to blood (16.7% in cervix and 13.3% in blood; P = 0.4). HIV-1-specific responses were detected the cervix of 8/10 women, with a trend to higher response frequencies in the genital tract than blood (2.1% versus 0.8%; P = 0.09). Co-expression of integrin CD103 (alpha E beta 7), a mucosal marker, was used to confirm the mucosal origin of cervical responses. CONCLUSIONS: Cytobrush sampling and intracellular cytokine staining is well suited to the analysis of cervical CD8 cell responses. The frequency of functional virus-specific CD3+/CD8+ T cells is similar in the genital tract and blood of HIV-1-infected women. The role of genital tract CD8 cell responses in HIV-1 control warrants further investigation