Regular Testing Needed for HIV PrEP, Study Shows

Several recent clinical trials demonstrated pre-exposure prophylaxis (PrEP) can effectively reduce the risk of HIV transmission and in Europe, which led the European Center for Disease and Prevention (ECDC) to recommend the integration of PrEP into national HIV prevention programs for those most at risk of HIV infection.

A survey conducted in 2018 and 2019 investigated testing frequencies and factors associated with intermittent testing among self-funded PrEP users in Germany. This stems from existing guidelines that found PrEP users are periodically tested for HIV, sexually transmitted infections (STIs), and renal function.

There were 4848 survey participants, and between 1 in 5 and 1 in 4 did not follow the recommended testing frequencies for HIV, STI, and renal function required in the German guidelines for PrEP use. Respondents who frequently tested for STI had higher proportions of self-reported STI diagnoses during PrEP use, overall and across levels of partner numbers and condom use.

According to the study authors, the strongest factors associated with less frequent testing were that respondents did not test before they started taking PrEP, they obtained PrEP from informal sources, and they used it on-demand or occasionally. Further, they concluded that infrequent testing such as this during PrEP use “can lead to missed diagnoses,” and barriers to testing should be addressed to enable proper medical supervision.

The study authors suggest that the most likely mode of transmission was sex with a person on antiretroviral treatment who was not virally suppressed at the time of HIV transmission. They added that further promotion of adherence to antiretroviral therapy among HIV-positive individuals is an important pillar in preventing onward transmission.

As for asymptomatic men who have sex with men (MSM) who use PrEP, regular STI screening and testing is just as important in this population because previous studies found a similar predominance of asymptomatic cohorts of MSM who would have been missed without testing.

REFERENCE

HIV pre-exposure prophylaxis works but needs regular testing. EurekAlert! April 7, 2022. Accessed April 18, 2022. https://www.eurekalert.org/news-releases/949068.