IgA Antibody Test Reveals HIV Status of Infants 3-6 Months of Age

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HIV-positive; among the Haitian children, all 13 of the children who were IgA positive were
confirmed to be HIV positive.
When the investigators confirmed and analyzed the results for all children who were 3
months of age or older, they found only 1 false positive and 4 false negative result out of a
total of 498 blood samples.
When the investigators analyzed the IgA blood tests by age, they found that 1 out of 6
HIV-infected children tested in the first month of life was IgA-positive (17 percent). At 3
months, 6 of 9 HIV-infected children were IgA-positive (66.7 percent), and at 6 months, 15
of 16 HIV-infected children were IgA positive (93.8 percent). After 6 months of age, all of
the samples drawn from 45 infected children were IgA-positive. The other 2 of the 47 HIVinfected children were lost to followup.
"We found that IgA antibodies are frequently absent during the first weeks of life in
children born to HIV-infected women," Dr. Quinn said. "In fact, we found IgA in only 1 out
of 5 babies we sampled in their first week, but it's also important to note that we had very
few samples from infants that young. Most of the HIV-infected babies that we studied
developed IgA between 3 and 6 months of age."
Dr. Quinn said that further studies should include analysis of more blood samples
obtained from infants between birth and 3 months of age, to more accurately assess the ability
of the IgA test to predict infection in very young infants, and to provide more information
about the timing of HIV transmission from mother to infant.

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