Time to roll out rapid testing for HIV? Yes, but with appropriate safeguards

Abstract

In a study published in this edition of Sexual Health, Wilson et al. using mathematical modelling, suggest that individuals with primary HIV infection and those who are HIV infected but undiagnosed, contribute disproportionately to new HIV infections among men who have sex with men. Based on these findings, they make the case for increased HIV testing to increase rates of HIV diagnosis. The diagnosis of HIV has clear benefits for HIV infected individuals as well as the population. For the individual, early diagnosis provides the opportunity for appropriate patient management and initiation of antiretroviral therapy at an optimal point in time, which can now offer the expectation of a near normal life span. In contrast, those who are diagnosed late have much poorer health outcomes at significant health service cost. It is a disheartening reflection of current testing strategies that a substantial proportion of people newly diagnosed with HIV still present at an advanced stage in their infection. In the UK, 31% of people newly diagnosed with HIV first present for testing when their CD4 count is less than 200. At the population level, early detection of HIV contributes to improved HIV control by enabling partner notification and evidence suggests that individuals diagnosed with HIV usually alter their sexual behaviour so as to reduce the risk of further HIV transmission. The benefits from increased HIV detection would be greatest in populations where the proportion of undiagnosed individuals is highest. In 2003, there were an estimated 1million persons infected with HIV in the USA with one-quarter of these persons unaware of their status. In the UK it is estimated that of the 77 400 people with HIV, 28% of them are unaware of their infection. These data highlight a pressing need for new approaches to reduce barriers to testing. So how might testing for HIV be substantially increased? One way is through the use of rapid testing for HIV using either a finger prick blood sample or a sample of oral fluid obtained by a mouth swab with results available at the point of testing within minutes. The use of rapid HIV testing confers a number of potential benefits which may reduce barriers to testing. Rapid testing removes the typical 1–2 week delay between test and result with conventional HIV blood tests. This is important as it is not uncommon for clients to express anxiety about this waiting period and this may actually deter individuals from testing. Recent studies suggest that clients favour rapid HIV testing over conventional testing, citing the immediacy of results as the main factor behind this preference. 10 The provision of a result at the time of testing has the added advantage of preventing loss of patients to follow up. In the USA, 31% of people who tested HIV positive in 2000 did not return for their test result. However, the implementation of rapid testing in New York State in 2003 meant that 100% of those tested received their result and led to a 36% increase in testing over the previous year resulting in increased detection of previously undiagnosed HIV. A further advantage of rapid HIV tests is that they are ideally suited to non-clinical or community settings, providing access to HIV testing to individuals who might not otherwise access clinical services for testing. Oral fluid sampling may confer added benefits to users over finger prick blood testing as it may be perceived as less invasive and is less painful. Given that oral fluid is not considered potentially infectious unless it contains blood, the disposal of samples is also much easier. Many settings have been proposed as outreach sites including bars, clubs and saunas, further education and sports settings. However, we must recognise that individuals need a choice of venues for testing to include both community and clinic-based settings, as people vary greatly in their preferences. One sauna based UK study of men who have sex with men reported that some men would not feel comfortable testing for HIV in a club as they feared the consequences of receiving a positive result in that setting. Rapid testing appears popular with health care professionals. Moreover, after training and experience with rapid testing, counsellors without previous laboratory training have shown proficiency in rapid testing and express a preference for rapid testing over conventional testing. A number of rapid HIV tests have been approved for use by the US Food and Drug Administration (US FDA). Some of these have only been approved for use within the laboratory setting, whereas others can be administered outside laboratories by persons without formal laboratory training. The OraQuick ADVANCE Rapid HIV-1/2 Antibody Test (OraSure Technologies, Bethlehem, PA, USA) stands out as it can provide CSIRO PUBLISHING Editorial