Rick, Hi. Do the current serology tests also indicate the particular subtype of HIV in those testing positive for antibodies? If not, which test is used for this? Thanks.

Hi. Thank you for your question. Serology tests for HIV do not determine the subtype or strain of HIV. They just determine if HIV is present or not. However, serology tests can specifically determine whether a person has HIV-1 vs. HIV-2. Remember however that HIV-2 is very rare outside of Western Africa. There is no clinical need to do subtype or strain testing in the vast majority of infected persons, since treatments and clinical follow-up are the same, regardless of the subtype. There are tests that determine the subtype/strain, but these are only available in research labs, and are not used for routine testing in persons with HIV. Tests are currently being developed to better detect drug resistant strains of HIV, but these, too, are strictly used in research labs at this time. The key here is that regardless of the subtype, treatment and clinical follow-up for HIV is the same. Therefore, subtype testing is usually unnecessary.

If you have any further questions, please feel free to call the Centers for Disease Control at 1.800.232.4636 (Nationwide).