Absence of transmission from HIV-infected individuals with HAART to their heterosexual serodiscordant partners

BACKGROUND

Further studies are needed to evaluate the level of effectiveness and durability of HAART to reduce the risk of HIV sexual transmission in serodiscordant couples having unprotected sexual practices.

METHODS

A cross-sectional study was conducted with prospective cohort of heterosexual HIV serodiscordant couples where the only risk factor for HIV transmission to the uninfected partner (sexual partner) was the sexual relationship with the infected partner (index case). HIV prevalence in sexual partners at enrolment and seroconversions in follow-up were compared by antiretroviral treatment in the index partner, HIV plasma viral load in index cases and sexual risk exposures in sexual partners. In each visit, an evaluation of the risks for HIV transmission, preventive counselling and screening for genitourinary infections in the sexual partner was performed, as well as the determination of the immunological and virological situation and antiretroviral treatment in the index case.

RESULTS

At enrolment no HIV infection was detected in 202 couples where the index case was taking HAART. HIV prevalence in sexual partners was 9.6% in 491 couples where the index case was not taking antiretroviral treatment (p<0.001). During follow-up there was no HIV seroconversion among 199 partners whose index case was taking HAART, accruing 7600 risky sexual exposures and 85 natural pregnancies. Among 359 couples whose index case was not under antiretroviral treatment, over 13,000 risky sexual exposures and 5 HIV seroconversions of sexual partners were recorded. The percentage of seroconversion among couples having risky sexual intercourse was 2.5 (95% confidence interval [CI]: 1.1-5.6) when the index case did not undergo antiretroviral treatment and zero (95% CI: 0-3.2) when the index case received HAART.

CONCLUSIONS

The risk of sexual transmission of HIV from individuals with HAART to their heterosexual partners can become extremely low.

[Analysis of the epidemiological pattern of Shigellosis in Barcelona between 1988 and 2012: Is it an emerging sexually transmitted infection?]

INTRODUCTION

The aim of this study was to describe the evolution and epidemiologic characteristics of shigellosis patients over a 25 year period in a large city.

METHODS

Shigellosis is a notifiable disease in Spain since 1988. Cases are analyzed in Barcelona residents included in the registry between 1988-2012. A descriptive analysis by sex, age, mode of transmission and Shigella species is presented. Trend analysis and time series were performed.

RESULTS

Of the 559 cases analyzed, 60.15% were males. A sustained increase was observed in the trend since 2008 in males (p<0,05), especially at the expense of males who had no history of food poisoning or travel to endemic areas. The increasing tendency was greater in males from 21 to 60 years, both for S. flexneri (since 2009), and for S. sonnei (since 2004). In 2012 it was noted that in the men with S. flexneri, the 63% were men who have sex with men.

CONCLUSIONS

An increased trend was detected in men who had no history of food poisoning or travel to endemic areas. This increase points to a change in the pattern of shigellosis, becoming predominantly male and its main mechanism probably by sexual transmission.