Discordant rapid HIV tests: lessons from a low-resource community.

OBJECTIVES: HIV rapid antibody tests are widely used in Africa, but dual testing sometimes produces discordant results. It is not clear if discordant rapid HIV tests should always heighten suspicion by frontline health workers that early HIV infection is present. Some studies have reported that discordant rapid tests have value for identifying early HIV infection in high HIV prevalence populations. It is not known if rapid test performance influenced this conclusion, or if this observation will hold true for low HIV prevalence populations. We therefore explored the occurrence of discordant rapid HIV tests in a low-resource community. METHODS: A cross-sectional sample of HIV status-unaware adults with recent exposure to unsafe sex was assessed using a validated risk-based tool (University of North Carolina (UNC)-Malawi Risk Screening Score) for acute HIV infection. Participants received rapid testing with Determine™ HIV 1/2 and Uni-Gold™ HIV assays, plus plasma HIV-1 antigen testing with the COBAS® Ampliprep/COBAS® Taqman® HIV-1 assay, followed by western blot in those with detected HIV-1 antigen. RESULTS: Of 408 participants, 1.0% were confirmed to have established HIV infection. The discordance between rapid tests at initial screening was 2.45 and 2.94% when the two assays were used sequentially and simultaneously, respectively. Discordant rapid tests were strongly associated with risk scores > 2 [odds ratio (OR) 10.88; 95% confidence interval (CI) 2.35-50.43], and with detected HIV-1 RNA (OR 26.06; 95% CI 3.91-173.60). CONCLUSIONS: When the sample occurrence of discordance between the first and second tests is below 5%, discordant rapid tests in an adult with sexual risk behaviour should trigger strong suspicion of early HIV infection in low HIV prevalence populations.

Obesity: an emerging disease.

Obesity is rapidly becoming an emerging disease in developing countries due to the increasing westernization of societies and change in the lifestyle. The etiology of obesity is said to be multifactorial, with a combination of genetic and environmental factors. Literature has been extensively reviewed to provide a broad overview of obesity. Data for this review were obtained from original articles, review articles and textbooks. Internet search engines were also employed. The years searched were from 1993 to 2008. Obesity, classified in terms of the body mass index and the waist-hip ratio, has several associated co-morbidities such as diabetes mellitus, hypertension, degenerative osteoarthritis and infertility. In Nigeria, there is limited information on obesity. A literature review on obesity is necessary to improve the knowledge about obesity in developing countries, its prevention and its management.