A rapid HIV test that has been available in the UK for more than four years, and which delivers results 15-minutes after taking a finger prick blood sample, has been found to be safe, reliable, easy-to-use and cost effective. The results of the validation study from London’s Chelsea and Westminster hospital were presented late last month at the annual British Association for Sexual Health and HIV (BASSH) conference in Bath.
Abbott Laboratories’ Determine HIV-1/2 test is an inexpensive immunochromatographic (lateral flow) device that detects antibodies to HIV-1 and HIV-2 in human serum, plasma and whole blood. It can be stored and transported at room temperature. After pre-test counselling, the rapid test is performed and 15 minutes later the result can be read. It is then given to the patient by the health adviser along with post-test counselling. The whole process takes around one hour.
The Chelsea and Westminster validation study enrolled 1623 individuals across four London-based GUM clinics, including The Victoria Clinic for Sexual Health, the John Hunter Clinic and the West London Centre for Sexual Health.
They found that the sensitivity of the test - the ability to detect all true positive results - was 100% (95% CI: 95.3%-100%) and the test’s specificity - the number of negative tests correctly identified as negative - was 99.9% (CI: 99.5%-100%), which compares very favourably with standard Enzyme immunoassay (EIA) tests used in routine HIV diagnosis.
Although there were no false negative tests, there were two false positive results, which were picked up on standard confirmatory testing.
Dr Alan McOwan, Director of Sexual Health at Chelsea and Westminster Healthcare NHS Trust, says that “the rapid HIV test has shown itself to be simple, quick, cost effective, reliable, and easily installed into the clinic environment using existing staff. It has allowed Chelsea and Westminster to offer a better service to its patients and I was amazed at just how quickly the new test became part of our routine offering.”
In addition, a patient satisfaction survey conducted at the two youchoose one hour testing centres at the Soho Centre and Lighthouse West London which use the rapid test, found that 26% of the 205 respondents said that the availability of the rapid HIV test was the main factor in their taking an HIV antibody test.
Despite the availability of the rapid HIV test in the UK since 1999, it has only been available at a handful of sites since then. A 2000 review from the UK Public Health and Laboratory Service found it to be highly sensitive and specific: comparable in sensitivity to laboratory tests in general use, though not quite as sensitive as the very best of modern tests, stressing that positive results would still need to be confirmed by another test method.
It is hoped that the Chelsea and Westminster’s validation study will lead to an increase in availability, which should reduce the anxiety created by the one week-plus waiting times currently experienced at many GUM clinics in the UK. The Chelsea and Westminster will now routinely offer the rapid test at their GUM clinics - including their youchoose outreach services at the Soho Centre and Lighthouse West London - to all people at high risk, including gay men, people who have had sex in high-risk countries, or those with a past history of intravenous drug use.
Further information on this website
HIV prevalence increases by 20% in UK in one year - news story
- overview of HIV testing, including rapid tests
Further information
Dewsnap C et al. Piloting the use of Rapid HIV testing. 2nd Joint Meeting BASHH/ASTDA, Bath, 2004.