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False positive and/or false negative HIV diagnosis using rapid tests is a major problem in resource limited settings. While HIV rapid testing increases access to HIV prevention and treatment, the effects of falsely diagnosing someone as HIV positive while the person is in fact not infected go beyond just exposing the person to toxic antiretroviral therapy ARVs if the person is eligible, to psychological distress which may be far reaching. A few examples of reports of HIV misdiagnosis can be found in literature


  1. False Positive HIV Diagnoses in Resource Limited Settings: Operational Lessons Learned for HIV Programmes. Leslie Shanks and Colleagues here report the summary of an audit of HIV testing programmes in three countries in Africa. The found that 44 people falsely diagnosed as HIV positive in Democratic Republic of Congo, two in Burundi and seven in Ethiopia. While they did not find any impact in the uptake of HIV rapid testing, they noted that some of these people were on ARV prophylaxis and others abandoned by their partners.

  2. The Evaluation of a Rapid In Situ HIV Confirmation Test in a Programme with a High Failure Rate of the WHO HIV Two-Test Diagnostic Algorithm. Derryk klarkowski from the same group (Medecins Sans Frontieres) observed that the WHO two-test algorithm for HIV testing using rapid test produced a high rate of false positivity(10.5%) warranting a change in the algorithm notably retesting double positive HIV blood specimen before clinical decisions. Most of these false positive samples had weak test lines.


Error rates of rapid HIV tests may be small, but may have a huge impact at population level. Consider for example, a false positive rate of 4%. In other words, only four out of every one hundred people are declared falsely positive. In a population of 8 million people tested, the rapid test will falsely detect 320000 people. If just 30% of these women are pregnant, they will be initiated on ARVs at least for the period when the risk of mother to child transmission is high. At worst, this could be for life following the recently recommended Option B+ approach for programs to prevent mother to child transmission of HIV. The same applies for false negative results. The implication in this case is that we miss the opportunity to arrest the spread of infection by linking hundreds of thousands of truly HIV positive individuals to care. In settings where the epidemic is generalized, such as in most sub-Saharan countries, the infection could continue to be a leading cause of death in especially mothers and young children.
Reasons for misclassification are multifactorial and reported by the WHO (http://www.who.int/hiv/pub/vct/retest-newly-diagnosed-plhiv-full/en/). They include poor quality tests, transport and storage conditions, non-compliance with testing procedure, poor choice of testing algorithm or challenges associated with interpretation of test results.
Currently, the WHO recommends retesting of all patients previously tested positive by rapid testing algorithms before clinical decisions and initiation on ARVs. The importance of quality assurance is is underscored in all processes and strategies of HIV rapid testing. The current 2013 WHO consolidated guidelines on the use of antiretroviral drugs for treating and preventing HIV infection (http://www.who.int/hiv/pub/guidelines/arv2013/en/ ) recommends expansion of HIV testing and counseling to communities using a variety of models that incorporate both testing and linkage to care. This should be implemented if the target of reducing the number of people with an undiagnosed infection by 2020 is to be attained. These strategies of testing depend on the nature of the epidemic. For regions or countries with generalized epidemic for example, strategies include

  1. Provider initiated testing in antenatal care, Tuberculosis treatment centres, STI treatment centres , among key affected populations and drop in centres.

  2. Home based testing

  3. Mobile outreach testing

  4. Workplace HIV testing

  5. School based testing

  6. Voluntary counseling and testing.


While all these strategies have the potential to increase access and uptake of HIV testing and counseling, questions remain among which the following can be explored and tested in studies of different designs:

  1. What optimal models of quality assurance to be put in place in different (especially community testing models) settings.

  2. In Africa, TB care and HIV in some countries are not integrated. This means that TB centres were not designed to test for HIV and manage the infection. The HIV clinics were not designed to provide the comprehensive care for TB patients. Referring HIV+ TB patients from TB centres to HIV clinics for care could lead to spread of TB infection when linkage is optimal or referral could lead to loss to follow up.

  3. What strategies to link adolescents to care when diagnosed in the community? A study in South Africa indicated that reminders using mobile applications could be effective in linking adolescents to care. A more comprehensive discussion on testing issues among adolescents can be found at http://www.ncbi.nlm.nih.gov/books/NBK217943/