Network of sexual contacts and sexually transmitted HIV infection in Burkina Faso

Two thirds of the people who have been infected by human immunodeficiency virus (HIV) in the world live in Sub-Saharan African countries. The results of a study measuring the degree distribution of the network of sexual contacts in Burkina Faso are described. Such a network is responsible for the spread of sexually transmitted diseases, and in particular of HIV. It has been found that the number of different sexual partners reported by males is a power law distribution with an exponent gamma = 2.9 (0.1). This is consistent with the degree distribution of scale-free networks. On the other hand, the females can be divided into two groups: the prostitutes with an average of 400 different partners per year, and females with a stable partner, having a rapidly decreasing degree distribution. Such a result may have important implications on the control of sexually transmitted diseases and in particular of HIV. Since scale-free networks have no epidemic threshold, a campaign based on prevention and anti-viral treatment of few highly connected nodes can be more successful than any policy based on enlarged but random distribution of the available anti-viral treatments.     

Early detection of HIV infection and of asymptomatic sexually transmitted infections among men who have sex with men

ObjectiveTo provide data on incidence of early diagnosis of HIV infections and define prevalence and incidence of asymptomatic sexually transmitted infections (STI) in men who have sex with men (MSM).MethodsWe assessed a prospective cohort study of HIV-uninfected MSM at high risk for HIV infection. Participants were selected through a risk-assessment questionnaire, and they were screened for HIV infection (quarterly) and for other STI (yearly): syphilis, and hepatitis A, B and C (serology); Chlamydia trachomatis and Neisseria gonorrhoeae in penis and rectum; and human papillomavirus in anus and mouth (PCR).ResultsBetween November 2009 and October 2012, a total of 258 HIV-uninfected MSM at high risk for HIV infection were included and followed up for a median of 2 years (interquartile range 1.4, 2.5). Nineteen acute HIV infections were diagnosed (incidence, 3.9 per 100 person-years). Prevalence of STI at baseline was follows: syphilis 8.4% (95% confidence interval (CI) 5.4–12.7); hepatitis C virus (HCV) 2.0% (95% CI 0.7–4.8); C. trachomatis in penis 3.2% (95% CI 1.5–6.5) and in rectum 6.5% (95% CI 3.9–10.5); N. gonorrhoeae in penis 2.0% (95% CI 0.8–5.0) and in rectum 6.1% (95% CI 3.6–10.1); human papillomavirus in anal canal 75.7% (95% CI 68.8–81.5) and in mouth 3.8% (95% CI 1.8–7.7).ConclusionsThe implementation of the Check-Ear Project in a MSM community centre allowed for the identification of early HIV infections and asymptomatic STI among MSM. The high incidence of HIV infections and the high prevalence of STI strongly support the recommendation of periodic screenings among sexually active MSM.     

Tackling sexually transmitted infection burden in Ugandan communities living in the United Kingdom: a qualitative analysis of the socio-cultural interpretation of disease and condom use

BackgroundDespite being in a different country and social environment, Ugandans living in the UK still reportedly have the lowest rates of condom usage and one of the highest incidences of STIs in UK. In Uganda, STIs and HIV prevalence has been reported to be on the increase. Understanding peoples'' beliefs and the attitudes that influence their behavior is a key factor to effectively designing control programs.MethodsA qualitative study that interviewed 37 purposively selected Ugandans living in the UK was conducted. Lay theories and interpretations were derived using thematic analysis.ResultsCondoms generally carried a lot of stigma and were perceived for use primarily in extramarital affairs and pregnancy control. HIV/AIDS was most feared due to its perceived socio-psychological or physical effects unlike other STIs described as “non-threatening” due to wide availability of “quality” treatment in UK. Notions of trust, the purpose of relationships, symptom recognition and partner selection greatly influenced decisions to undertake consistent condom use.ConclusionsThe socio-cultural understanding of STIs, sex, trust and relationships are symbolic in influencing consistent condom use among Ugandans. This indicates a need to acknowledge community beliefs and values about sexual health and design messages about STIs and condoms that would help eliminate these serious condom-related misconceptions.     

Polymorphism of human papillomavirus type 31 isolates infecting the genital tract of HIV-seropositive and HIV-seronegative women at risk for HIV infection

The genomic polymorphism of high-risk human papillomavirus (HPV) for types other than 16 has not been extensively described. We describe here the genomic polymorphism of high-risk HPV type 31 in 79 women (62 HIV-seropositive, 17 HIV-seronegative) by PCR-sequencing of the long control region (LCR), E6 and E7. LCR polymorphism was generated by 25 (6.4%) single-nucleotide variations over 391 bases. Each variant compared to the prototype contained from 2 to 13 variations (mean of 9.4 +/- 3.3, median of 10). Considering the number of variation sites in each region of HPV genome, the LCR was more variable than E6 (13 over 496 nucleotide (nt), P=0.03) and E7 (9 over 296 nt, P=0.03). Non-synonymous nucleotide variations were found in 31 (75.6%) of 41 isolates and were observed at six positions in E6. Each of the 8 HPV-31 E7 variants contained from 2 to 5 mutations (mean of 4.29 +/- 1.11, median of 5) compared to the prototype. Three non-synonymous E6 and E7 variations were within cysteine arrays. The LCR prototype was significantly over-represented in Caucasian women (14 (25%) of 56) compared to women of African descent (0 (0%) of 15 women, P=0.03). Four (23.5%) of 17 women with persistent versus 6 (25.0%) of 24 women with transient infections were infected by the prototype (P=1.00). HPV-31 LCR was more polymorphic than oncogenes and was associated with ethnicity.