30 year GBMSM presented to our sexual health service requesting PrEP. He was taking PEP after a sexual exposure and was keen to transition straight to PrEP. Baseline testing including HIV were negative before PEP was initiated.

He was given a supply of PrEP and returned for HIV testing post PEP as per BASHH guidelines. He reported a recent Covid infection confirmed by PCR testing. We carried out a rapid Abbott Determine Early Detect HIV test which was reactive. The assay is a 4th generation test that detects both HIV-1/2 antibodies and free HIV-1 p24 antigen.

The patient was advised of this test result and a repeat rapid test the same day remained reactive. He was advised that this could be as a result of recent Covid infection resulting in a cross reaction and that we would await confirmatory testing. He was advised to discontinue PrEP until the result was clarified.

Laboratory testing was requested expeditiously and the sample tested on 2 different immunoassay analyzers for the detection of HIV Ab/Ag. Both results were confirmed negative and he was advised to restart the PrEP.

A literature search showed that cross reaction with the HIV rapid test had been reported after recent Covid 19 infection in other centres but not in the UK.

He was seen 4 weeks later for further screening and rapid HIV testing on this occasion was negative together with the virology HIV immunoassay test. The patient was tested for COVID at the same time and was PCR negative at this stage.