New research by online sexual health provider SH:24, published in the BMJ Journal Sexually Transmitted Infections, could change the way home HIV tests are interpreted, and improve the care provided to people testing for HIV.
Research by the UK Health Security Agency found that the number of people testing for HIV using online services rose by 70% between 2019 and 2020. Online services now account for around half of all HIV tests undertaken in England.
Traditional testing in a clinic collects a large blood sample and the laboratory will do three tests. The first is the most sensitive. If that is negative then you are very unlikely to have HIV. If it is reactive then two further tests are done to check that this is a true positive.
With home tests, people collect a smaller blood sample, enough only for the first test. For most people this is negative and they do not have HIV and they don’t need to worry – this is a very sensitive test.
However a small number of these tests are reactive. Some of the people with reactive tests will have HIV and some of them will not, as the test may be over-sensitive. Everyone with a reactive test result is recommended to visit a clinic to get a confirmatory test. However, our new research gives us a new measure – the reactivity level – which can tell us how likely it is that a reactive result will be confirmed as a true HIV infection.
This is not completely reliable, but it gives sexual health professionals an idea and it can help with counselling. Counselling is important to help people think about their risk of HIV, reduce it in the future if possible and also to help manage anxiety while people wait to go to a clinic to do confirmatory tests.
This research was undertaken in the UK but has implications for HIV home testing services worldwide.
Paula Baraitser, Consultant in Sexual Health, Director of SH:24 and one of the authors of the paper told QX:
‘The period between receiving a reactive HIV test and going to clinic for confirmatory test can be an anxious time. This research will help clinicians in online services deliver bespoke counselling for each service user. The extra information can reduce anxiety for those with low reactivity levels while they wait for testing in clinic. We know that online services increase access to testing and that user satisfaction is already high. This innovation should make it even better.’
