Objective: To investigate longitudinally the association between highly active antiretroviral therapy (HAART)-related beliefs and the change from protected to unprotected anal intercourse with casual partners on an individual level. Methods: The study population included 217 HIV-negative homosexual men participating in the Amsterdam Cohort Study from September 1999 to May 2002, including five data waves with a 6-month interval. The selection criteria were: being under 31 years of age, having had anal sex with casual partners in the preceding 6 months, and participating in at least two data waves. Information was collected on the individual change from protected to unprotected receptive anal intercourse (URAI) and unprotected insertive anal intercourse (UIAI) and the level of agreement with different HAART-related beliefs. Results: The majority of men disagreed with the three treatment-belief factors that resulted from the principal component analysis: perceiving less HIV/AIDS threat since HAART, perceiving less need for safe sex since HAART, and perceiving high effectiveness of HAART in curing HIV/AIDS. Multivariate analyses revealed that the more men inclined to agree with the belief ‘perceiving less HIV/AIDS threat', the more likely they were to change to URAI (adjusted OR 1.60; 95% CI 1.16–2.22). Conclusion: Homosexual men are quite realistic about the effectiveness of HAART, the continued need for condom use, and the HIV/AIDS threat since HAART. However, a tendency towards agreement with ‘perceiving less HIV/AIDS threat’ was found to predict an individuals’ change to URAI. This finding supports the hypothesis of a causal relationship between decreased HIV/AIDS threat since HAART and a change to URAI.

To evaluate the effect of highly active antiretroviral therapy (HAART) on the sexual behaviour of homosexual men, we conducted (i) an ecological study of time trends in sexual behaviour and sexually transmitted diseases; (ii) a HAART-effect study focused on the practice of unprotected anogenital sex. Subjects were participants in the ongoing Amsterdam Cohort Studies (ACS) among homosexual men, initiated in 1984. Data for (i) represented all ACS visits by HIV-1-positive and -negative participants who entered ACS at or below 30 years of age and were followed until 35 years (n = 1062). Data for (ii) represented all ACS visits of HIV-1-positive men from 1992 to 2000 (n = 365), of whom 84 were HAART recipients with at least 2 months of behavioural follow-up. (i) After HAART became generally available in July 1996, unprotected sex was practised more frequently and the incidence of gonorrhoea was higher compared to March 1992–June 1996 among HIV-1-negative and -positive men, respectively. (ii) Among HIV-1-positive men, a higher level of unprotected sex with casual partners was observed after HIV-1 RNA became undetectable and CD4 cell counts increased with the use of HAART. Notably, in individuals who did not receive HAART, high HIV-1-RNA levels (above 105 copies/ml) were likewise related to unprotected sex with casual partners. Data support the need for the reinforcement of safe sex prevention messages among HIV-1-negative men, and our data also provide a lead for redirecting and tailoring current prevention strategies to the needs of HIV-1-positive men.

In China, in the early 1980s, sexually transmitted diseases (STD) started to increase steeply. Sex workers and their clients appeared to play an important role in the spread of STD. Prostitution is illegal in China, and therefore no specific services exist for sex workers unless they are arrested and detained in re-education centres. Staff of a maternal and neonatal hospital in Guangzhou felt the need for an STD care and prevention programme for sex workers outside detention, and started a programme within their hospital, which was unique in the Chinese context. From March 1998 to mid-October 1999 sex workers were recruited through various outreach methods, and were interviewed, counselled and examined for the presence of STD/HIV. A total of 966 women, originating from all over China but working in Guangzhou, entered the programme. The median duration of prostitution was one year, and the median number of clients was seven per week. Antibodies to HIV were present in 1.4%. The prevalence of STD was very high: syphilis 14%, Chlamydia trachomatis 32%, gonorrhoea 8% and trichomoniasis 12.5%. Knowledge about STD/HIV transmission and condom use was poor. Given the high prevalence of STD, the potential for the further spread of HIV is clearly present. STD care and prevention programmes for these women, outside detention, are urgently needed, and appear also to be feasible in China.

The finding of antibodies against human herpesvirus 8 (HHV-8) is associated with the occurrence of Kaposi's sarcoma in persons infected with HIV. However, the predictive value of HHV-8 antibodies for Kaposi's sarcoma in HIV infection is unknown. The Amsterdam Cohort Studies on HIV infection and AIDS started in 1984 for homosexual men and in 1985 for injecting drug users. Serum samples from 1459 homosexual men and 1167 drug users were tested for antibodies to recombinant HHV-8 lytic-phase capsid (ORF65) antigen and latent-phase nuclear (ORF73) antigen. Individuals were retrospectively identified as HHV-8-positive or HHV-8-negative at enrolment or HHV-8 seroconverter during the study. Kaposi's sarcoma-free survival time was compared between HIV-infected men who were positive for HHV-8 at enrolment and those who later seroconverted for HHV-8. Hazard ratios were estimated for Kaposi's sarcoma, lymphoma, and opportunistic infection according to the HHV-8 serostatus. The incidence of HHV-8 seroconversion among drugs users was 0.7 per 100 person-years based on 31 seroconversions, whereas an incidence of 3.6 was found among homosexual men based on 215 seroconversions. The hazard ratio for Kaposi's sarcoma was 3.15 (95% CI: 1.89–5.25) in HIV-infected individuals if HHV-8 antibodies were present either at enrolment or at HIV seroconversion. In HIV-infected persons who later seroconverted to HHV-8, Kaposi's sarcoma developed more rapidly: hazard ratio of 5.04 (95% CI: 2.94–8.64), an additional risk of 1.60 (95% CI: 1.01–2.53; P = 0.04). Time-dependent adjustment for CD4+ cell count and HIV RNA had no impact on the additional risk, although the CD4+ cell count was an independent risk factor for Kaposi's sarcoma. HHV-8 infection did not increase the risk of AIDS-related lymphoma or opportunistic infections. The incidence of HHV-8 infection is higher in homosexual men than in drug users. The presence of HHV-8 antibodies in HIV-infected persons increases the risk of Kaposi's sarcoma. Among HIV-infected persons, those who subsequently seroconvert for HHV-8 are at highest risk. These results strongly confirm the causal role of HHV-8 in Kaposi's sarcoma and emphasize the clinical relevance of HHV-8 seroconversion before and after the HIV infection.

We evaluated the risk of pelvic inflammatory disease (PID), ectopic pregnancy, and infertility in women with a previous Chlamydia trachomatis (CT) diagnosis compared with women who tested negative for CT and CT untested women, considering both targeted and incidental (ie, prescribed for another indication) use of CT-effective antibiotics. This was a retrospective study of women aged 12–25 years at start of follow-up within the Clinical Practice Research Datalink GOLD database linked to index of multiple deprivation quintiles, 2000–2013. CT test status and antibiotic use were determined in a time-dependent manner. Risk of PID, ectopic pregnancy, or female infertility were evaluated using of Cox proportional hazard models. We studied 857 324 women, contributing 6 457 060 person-years. Compared with women who tested CT-negative, women who tested CT-positive had an increased risk of PID (adjusted hazard ratio [aHR], 2.36; 95% confidence interval [CI], 2.01–2.79), ectopic pregnancy (aHR, 1.87; 95% CI, 1.38–2.54), and infertility (aHR, 1.85; 95% CI, 1.27–2.68). The PID risk was higher for women with 2 or more positive CT tests than those with 1 positive test. PID risk increased with the number of previous antibiotic prescriptions, regardless of CT test status. We showed an association between CT-positive tests and 3 adverse reproductive health outcomes. Moreover, this risk increased with repeat CT infections. CT-effective antibiotic use showed no decreased risks of subsequent PID regardless of CT history. Our results confirm the reproductive health burden of CT, which requires adequate public health interventions.

Objectives: We investigated if a rise in rectal gonorrhoea and early syphilis among men who have sex with men (MSM) in Amsterdam coincided with the introduction of highly active antiretroviral therapies (HAART) in July 1996 and determined risk factors for these sexually transmitted infections (STI). Methods: Subjects were patients of the STI clinic of the municipal health service in Amsterdam. Surveillance data (1994–9) represented consultations (n=11 240) of MSM (n=6103). For analyses we used logistic regression. Results: Comparing the periods before and after the introduction of HAART, the infection rate for rectal gonorrhoea increased from 4% to 5.4% (p=.001) and for syphilis, from 0.5% to 0.8% (p = 0.050). Independent risk factors for rectal gonorrhoea (younger age, western nationality, and concurrent infection with another STI) and for early syphilis (non-western nationality and concurrent infection with rectal gonorrhoea) did not change after HAART became available. For rectal gonorrhoea, however, the infection rate increased only among men who had exclusively homosexual contacts (OR 1.38, p<0.01), compared with bisexual men. For early syphilis, the infection rate increased only among men of western nationality (OR 3.38, p<0.01) compared to men of non-western nationality. Conclusions: Infection rates of rectal gonorrhoea and early syphilis increased, indicating a change in sexual behaviour, possibly as a result of the introduction of HAART. For now, it is important to find out how sexual behaviour is changing and to keep monitoring trends in STIs (including HIV) among MSM in Amsterdam.