What laboratory method is routinely adopted for screening individuals for HIV infection? ?
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Answer: C. ELISA followed by western blot technique
Explanation
HIV screening protocols begin with a highly sensitive enzyme-linked immunosorbent assay to detect antibodies. Any reactive initial screening results are subsequently confirmed using a highly specific Western blot assay. This two-step testing algorithm ensures high diagnostic accuracy by eliminating potential false positives. Screening tests prioritize high sensitivity to ensure all potential infections are initially caught. Confirmatory tests prioritize high specificity to verify the presence of specific viral antibodies. Modern diagnostic laboratories also utilize specialized molecular viral load tests alongside serology.
Accurate HIV diagnosis is critical for initiating timely antiretroviral therapy and counseling patients. Public health surveillance programs rely on standardized testing algorithms for accurate data collection. Ensuring test reliability prevents unnecessary psychological distress caused by initial false-positive results. Direct virus isolation is technically demanding and rarely used as a routine screening method. Performing the Western blot before the ELISA is backwards and unnecessarily expensive for primary screening. Polymerase chain reaction tests are powerful molecular tools but are not the standard initial screening method.
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