The London sexual health clinic 56 Dean Street saw a dramatic decline in its rate of prescribing post-exposure prophylaxis (PEP) against HIV after the United Kingdom instituted lockdown measures on March 23 in response to the novel coronavirus pandemic.

Investigators from the clinic, which in 2018 wrote one quarter of the 12,000 PEP prescriptions in the U.K., described their post-lockdown shift in PEP prescribing in a letter published in The Lancet HIV.

During the lockdown period, 56 Dean Street limited some face-to-face services. However, PEP is still offered on a walk-in basis.

During 2020, weekly rate of PEP prescriptions from the clinic peaked at 54 prescriptions during February 17 to 23, falling to four prescriptions during March 30 to April 5.

During the four-week period spanning January 20 and February 16, the clinic wrote 161 PEP prescriptions, compared with 28 prescriptions during the first four weeks of the lockdown, March 23 to April 19.

The majority of people receiving PEP during both those periods were men, and most had sought out PEP because they had had condomless receptive anal intercourse. The median age of those receiving PEP was 32 years during both the pre- and post-lockdown periods.

The proportion of people seeking PEP after having group sex did not change after the lockdown.

However, post-lockdown, people seeking PEP were more likely to have engaged in “chemsex,” in which people engage in sex while taking crystal meth, mephedrone, ketamine or GHB, or in “slamsex,” in which people inject any of those substances in a sexual context.

The letter’s authors theorized that the most obvious explanation for the decline of PEP prescriptions after the lockdown is that people are having less condomless sex. This would suggest that HIV transmissions would decline during the lockdown. 

Or it’s possible people are reluctant to travel to the clinic, which, if rates of condomless sex have not declined, would suggest that HIV transmissions could increase during the lockdown.

To read the study, click here.