Showing papers by "Myron S. Cohen published in 2004"

The role of sexually transmitted diseases in HIV transmission

Abstract: Factors that increase transmission Factors that increase susceptibility STDs and HIV transmission STDs and community-based studies More than 42 million people worldwide are now infected with HIV, in spite of sustained prevention activities. Although the spread of HIV has been primarily sexual, epidemiological studies have indicated that the efficiency of the spread of HIV is poor, perhaps as infrequently as 1 in every 1,000 episodes of sexual intercourse. However, sexually transmitted diseases (STDs) that cause ulcers or inflammation greatly increase the efficiency of HIV transmission — by increasing both the infectiousness of, and the susceptibility to HIV infection. STDs might be particularly important in the early stages of a localized HIV epidemic, when people with risky sexual behaviour are most likely to become infected. In China, eastern Europe and Russia, there has been a remarkable increase in the incidence of STDs in recent years, and this is reflected in the rapid increase in the spread of HIV in these areas. Targeted STD detection and treatment should have a central role in HIV prevention in these emerging epidemics.

Brief but efficient: acute HIV infection and the sexual transmission of HIV.

Abstract: Background. We examined whether viral dynamics in the genital tract during the natural history of acute human immunodeficiency virus type 1 (HIV-1) infection could explain efficient heterosexual transmission of HIV. Methods. We measured HIV-1 concentration in blood and semen samples from patients with acute and longterm HIV-1 infection. We explored the effect of changes in viral dynamics in semen on the probability of transmission per coital act, using a probabilistic model published elsewhere. Results. Considered over time from infection, semen HIV-1 concentrations, in men with acute infection, increase and decrease in approximate parallel with changes occurring in blood. Modeling suggests that these acute dynamics alone are sufficient to increase probability of heterosexual transmission by 8‐10-fold between peak (day 20 after infection, based on the model) and virologic set points (day 54 and later after infection). Depending on the frequency of coitus, men with average semen HIV-1 loads and without sexually transmitted diseases (STDs) would be expected to infect 7%‐24% of susceptible female sex partners during the first 2 months of infection. The predicted infection rate would be much higher when either partner has an STD. Conclusions. Empirical biological data strongly support the hypothesis that sexual transmission by acutely infected individuals has a disproportionate effect on the spread of HIV-1 infection. Acute hyperinfectiousness may, in part, explain the current pandemic in heterosexual individuals.

Prevalence of chlamydial and gonococcal infections among young adults in the United States.

Abstract: ContextChlamydial and gonococcal infections are important causes of pelvic inflammatory disease, ectopic pregnancy, and infertility. Although screening for Chlamydia trachomatis is widely recommended among young adult women, little information is available regarding the prevalence of chlamydial and gonococcal infections in the general young adult population.ObjectiveTo determine the prevalence of chlamydial and gonoccoccal infections in a nationally representative sample of young adults living in the United States.Design, Setting, and ParticipantsCross-sectional analyses of a prospective cohort study of a nationally representative sample of 14 322 young adults aged 18 to 26 years. In-home interviews were conducted across the United States for Wave III of The National Longitudinal Study of Adolescent Health (Add Health) from April 2, 2001, to May 9, 2002. This study sample represented 66.3% of the original 18 924 participants in Wave I of Add Health. First-void urine specimens using ligase chain reaction assay were available for 12 548 (87.6%) of the Wave III participants.Main Outcome MeasuresPrevalences of chlamydial and gonococcal infections in the general young adult population, and by age, self-reported race/ethnicity, and geographic region of current residence.ResultsOverall prevalence of chlamydial infection was 4.19% (95% confidence interval [CI], 3.48%-4.90%). Women (4.74%; 95% CI, 3.93%-5.71%) were more likely to be infected than men (3.67%; 95% CI, 2.93%-4.58%; prevalence ratio, 1.29; 95% CI, 1.03-1.63). The prevalence of chlamydial infection was highest among black women (13.95%; 95% CI, 11.25%-17.18%) and black men (11.12%; 95% CI, 8.51%-14.42%); lowest prevalences were among Asian men (1.14%; 95% CI, 0.40%-3.21%), white men (1.38%; 95% CI, 0.93%-2.03%), and white women (2.52%; 95% CI, 1.90%-3.34%). Prevalence of chlamydial infection was highest in the south (5.39%; 95% CI, 4.24%-6.83%) and lowest in the northeast (2.39%; 95% CI, 1.56%-3.65%). Overall prevalence of gonorrhea was 0.43% (95% CI, 0.29%-0.63%). Among black men and women, the prevalence was 2.13% (95% CI, 1.46%-3.10%) and among white young adults, 0.10% (95% CI, 0.03%-0.27%). Prevalence of coinfection with both chlamydial and gonococcal infections was 0.030% (95% CI, 0.18%-0.49%).ConclusionsThe prevalence of chlamydial infection is high among young adults in the United States. Substantial racial/ethnic disparities are present in the prevalence of both chlamydial and gonococcal infections.

Trichomoniasis: clinical manifestations, diagnosis and management

Abstract: Trichomonas vaginalis was originally considered a commensal organism until the 1950s when the understanding of its role as a sexually transmitted infection (STI) began to evolve. Trichomoniasis has been associated with vaginitis, cervicitis, urethritis, pelvic inflammatory disease (PID), and adverse birth outcomes. Infection with T vaginalis could have an important role in transmission and acquisition of HIV. T vaginalis is site specific for the genitourinary tract and has been isolated from virtually all genitourinary structures. Asymptomatic disease is common in both men and women, thus screening for disease is important. Various sociodemographic factors have been correlated with presence of T vaginalis, and may be used to predict infection. Diagnosis is usually made from wet mount microscopy and direct visualisation, which are insensitive. DNA amplification techniques perform with good sensitivity, but are not yet approved for diagnostic purposes. In areas where diagnostic methods are limited, management of trichomoniasis is usually as part of a clinical syndrome; vaginal discharge for women and urethral discharge for men. A single dose of metronidazole is effective in the majority of cases. Outside of the United States, other nitroimidazoles may be used and are as effective as metronidazole. Metronidazole resistance is an emerging problem, but its clinical importance is not yet clear. Concomitant treatment of sexual partners is recommended.

Acute HIV revisited: new opportunities for treatment and prevention

Abstract: Inability to recognize incident infection has traditionally limited both scientific and public health approaches to HIV disease. Recently, some laboratories have begun adding HIV nucleic acid amplification testing to HIV diagnostic testing algorithms so that acute (antibody-negative) HIV infections can be routinely detected within the first 1–3 weeks of exposure. In this review article, we will highlight critical opportunities for HIV treatment and prevention that are presented by these diagnostic strategies.

HIV and sexually transmitted diseases: lethal synergy.

Abstract: Sexually transmitted diseases (STDs) can increase risk for acquisition and transmission of HIV via a number of mechanisms, including breaching of mechanical barriers to infection, increased inflammation and higher levels of HIV cellular targets, and increased genital tract HIV levels. Studies in Malawi clinic populations indicate that treatment of STDs can reduce genital tract HIV levels. Work in Africa and India has indicated that genital herpes infection is associated with increased risk of acquisition of HIV and that presence of genital ulcer disease is associated with increased risk of transmission of HIV disease. Acute HIV infection has been found to be more frequent in individuals with active STDs, and co-transmission may be a common phenomenon. Acute HIV infection, which is not currently routinely diagnosed, is associated with increased risk of transmission. Greater efforts are needed in identifying acute HIV infection in STD clinics. This article summarizes a presentation by Myron S. Cohen, MD, at the International AIDS Society-USA course in Chicago in May.

HIV／AIDS risk among brothel-based female sex workers in China： Assessing the terms, content, and knowledge of sex work

Abstract: Sexual transmission of HIV in China is rapidly increasing in part driven by commercial sex work. This article examines variations in occupational control among one type of brothel-based prostitutes in China and the relationship between the terms and content of this work and the risk of HIV/AIDS. Organizational factors are discussed as part of the current political economic and social context of sex work in China. The analysis is based on ethnographic observation and in-depth interviews conducted in south China in 2000 and 2001 involving 158 female prostitutes from 45 brothels in 4 red light districts. Qualitative analysis of interview and observational data used development of thematic codes measuring occupational control. Brothel-based female sex workers in China are a heterogeneous population displaying considerable variability in the organization of life and work relationships with managers and clients ability to negotiate condom use knowledge of sexually transmitted diseases and HIV and occupational identity all of which may result in different risks of acquiring HIV. HIV prevention activities in China must focus on sociocultural aspects of sex work. Such interventions depend on detailed knowledge of its organization. The results of this study demonstrate the importance of prevention activities directed at the brothel managers and clients as well as the sex workers. (authors)

Frequent detection of acute primary HIV infection in men in Malawi

Abstract: Acute (antibody-negative) HIV infection is associated with high transmission potential but is rarely recognized. Design: Cross-sectional study. We examined the prevalence and predictors of acute HIV infection among 1361 consecutive male outpatients attending sexually transmitted disease (STD; n = 929) and dermatology (n = 432) clinics in Lilongwe Malawi. Serum specimens negative for HIV antibodies were screened by HIV RNA PCR using a highly specific pooling/resolution testing algorithm. Five-hundred and fifty-three men (40.6%) were HIV antibody positive and 24 (1.8%) had acute HIV infection; 23 of 24 acutely infected men were from the STD clinic where they represented 4.5% of all HIV antibody-negative men and 5.0% of all HIV infections. HIV RNA levels for acutely infected men were significantly higher [median (interquartile range) 6.10 (5.19–6.54) log/10 HIV RNA copies/ml] than for 58 HIV antibody-positive men [4.42 (3.91–4.95) log/10 copies/ml; P < 0.0001]. The factor most strongly associated with acute HIV infection was STD clinic attendance: (odds ratio 15.2; 95% confidence interval 2.04–113.0). In multivariate analysis considering only STD patients factors associated with acute HIV infection included inguinal adenopathy genital ulceration and age 24–26 years the age stratum associated with peak incidence of HIV infection among Malawian men. Traditional HIV antibody tests alone are not sufficient to exclude HIV infection among men with acute STD in Malawi due to a surprising proportion of acute HIV infections in this population. Alternative screening methods are required for diagnosis of acute HIV infection; such screening could be important for research and for prevention of the sexual transmission of HIV in select populations. (authors)

Protease inhibitor and nonnucleoside reverse transcriptase inhibitor concentrations in the genital tract of HIV-1-infected women.

Abstract: The pharmacokinetics of antiretrovirals (ARVs) in the female genital tract (FGT) are likely to influence vertical and sexual transmission of HIV, the development of viral resistance, and post-exposure prophylaxis regimens. This study is the first to compare ARV concentrations in direct aspirates of cervicovaginal fluid (CVF) and blood plasma (BP). This unique method provides direct assessment of concentrations without the confounding of cervicovaginal lavage dilution. Of 8 ARVs, CVF concentrations ranged from 100% of BP concentrations. These large differences in CVF penetration suggest that further research into ARV pharmacokinetics and drug efficacy in the FGT is necessary.

Targeted screening for Trichomonas vaginalis with culture using a two-step method in women presenting for STD evaluation.

Abstract: Objectives: Trichomonas vaginalis is the most common nonviral sexually transmitted pathogen. Wet mount microscopy performs poorly compared with culture; however, universal screening using culture would be cost-prohibitive. Goal: The goal of this study was to develop a predictive model for wet mount-negative women who may benefit from targeted use of culture for T. vaginalis detection. Study: Women presenting for sexually transmitted disease evaluation were prospectively screened for trichomoniasis using wet mount and culture. Multivariate logistic regression was used to identify predictors of culture-proven trichomoniasis among wet mount-negative women. Results: A total of 2194 women were screened for trichomoniasis; overall, the prevalence of T. vaginalis was 17.5%. Three predictors (any drug use, contact to trichomoniasis, and African-American race) provided the most specific model (100%); any 1 predictor, the most sensitive model (97.8%). Conclusions: Given the public health impact of trichomoniasis, we recommend using any 1 of 3 predictors to identify women who would benefit from targeted culture for T. vaginalis.

The Use of Specimens from Various Genitourinary Sites in Men, to Detect Trichomonas vaginalis Infection

Abstract: Variations in estimates of prevalence of trichomoniasis in men may reflect true differences in the burden of disease but are also affected by the performance of diagnostic methods and the type of specimen tested. In this study, men were evaluated at baseline and at follow-up, to evaluate syndromic management of urethritis and the effects of human immunodeficiency virus and trichomoniasis, in Lilongwe, Malawi. First-void urine specimens and urethral swabs were obtained at enrollment, for Trichomonas vaginalis culture; semen specimens were also obtained at follow-up. The sensitivities of testing methods using urine specimens and urethral swabs were equal; 67% of cases were identified by use of either specimen, and, in 47% of cases, both specimens tested positive. When semen specimens were included, all 3 specimens tested positive in only 19% of cases. Semen was the most sensitive single specimen, and, in 25.6% of cases, only semen specimens tested positive. Thus, prevalence of T. vaginalis infection in men is underestimated if only 1 specimen is tested.

Trichomoniasis in men and HIV infection: Data from 2 outpatient clinics at Lilongwe Central Hospital, Malawi

Abstract: Background. Little is known about the epidemiologic profile of trichomoniasis in men and its relationship to human immunodeficiency virus (HIV) infection. Among men presenting for care for symptomatic sexually transmitted infections (STIs) in Malawi, trichomoniasis is not considered for first-line treatment. Methods. We conducted a cross-sectional survey of 1187 men attending either a dermatology or STI outpatient clinic in the capital of Malawi. Men were interviewed, and the etiologies of the STIs were determined. Results. At the STI clinic ( men), we identified 150 men (20%) with Trichomonas vaginalis infection, n p 756 358 men (47%) with HIV infection, and 335 men (44%) with Neisseria gonorrhoeae infection. At the dermatology clinic ( men), we identified 54 (13%), 118 (27%), and 2 (0.5%) men, respectively. At both clinics, a lower n p 431 education level and reporting never having used a condom were predictive of T. vaginalis infection. Only at the dermatology clinic was older age associated with infection, and only at the STI clinic were marital, genital ulcer disease, and HIV-infection status associated with T. vaginalis infection. At the STI clinic, urethral symptoms attributable to trichomoniasis were more severe among HIV-positive men than among HIV-negative men. Conclusions. Given its high prevalence and the increased risk for HIV transmission, T. vaginalis infection should be reconsidered for inclusion in the Malawi STI-treatment regimen for men.

Online HIV/STI Chinese clinician training

Abstract: The spread of HIV in China is accelerating and many Chinese physicians are poorly trained to address it.1 We review clinician training and the internet in China, and present the results of a convenience sampling of 136 Chinese clinicians regarding their access and attitudes towards computer based HIV/STI training. Having been trained in an era of virtual STI eradication, many Chinese physicians are inadequately prepared to respond to the current HIV epidemic.2 Medical school curricula frequently lack STI coursework, and a European Union-China Project (EUCP) study in 2000 showed as few as 5% of physicians had ever received any HIV/STI …