Physician/researchers at Emory, the University of North Carolina at Chapel Hill and the Georgia Department of Human Resources used NAAT to screen clients receiving routing HIV testing and counseling at the urban clinics between October 2002 and January 2004. The research team used both standard antibody testing and NAAT testing to screen specimens from 2,202 people who had not previously tested positive for HIV. Sixty-six of the specimens were found to be HIV antibody positive and 2,135 were HIV antibody negative using standard tests. Using NAAT, however, four of the antibody-negative specimens tested positive for HIV viral genes.
On further examination, three of those four individuals were found to have definite acute HIV infections, although only one showed clinical symptoms. One of the four individuals had unclear results and may have had either acute or chronic HIV. In addition, three of the four individuals had HIV viruses with multidrug resistance. The fourth sample was unable to be tested for resistance.
Although standard tests that measure antibody response to the HIV virus have become increasingly sensitive, cases of HIV are occasionally missed because individuals can have negative antibody tests during the early stages of infection. Also, a few people with long-term HIV infection may have false-negative antibody tests or may be chronic carriers who are clinically asymptomatic. The NAAT test helps
Contact: Holly Korschun
Emory University Health Sciences Center