Which statement is true regarding HIV antibody testing in infants?

Which statement is true regarding HIV antibody testing in infants?

• A. Maternal antibodies can cause false-positive results in antibody tests.
• B. Maternal antibodies always interfere with antibody tests.
• C. Maternal antibodies never interfere with antibody tests.
• D. Maternal antibodies always disappear by six months.

Answer: (A)

Maternal IgG crosses the placenta, so an infant can have HIV antibodies even if the baby isn’t infected. Antibody tests detect antibodies, not the virus, so a positive result in a baby can reflect the mother’s antibodies rather than the infant’s status. That’s why maternal antibodies can cause false-positive antibody tests in infants. It isn’t correct to say they always interfere—interference can occur, but it isn’t guaranteed for every test or every infant. It’s also incorrect to claim they never interfere. Maternal antibodies don’t always disappear by six months; they typically wane over the first year and are usually gone by 12–18 months, but they can persist longer in some cases. Because of these factors, diagnosing HIV in infants relies on virologic tests (like HIV DNA PCR or RNA) to detect the virus itself, with antibody testing used mainly after maternal antibodies have cleared.

Maternal IgG crosses the placenta, so an infant can have HIV antibodies even if the baby isn’t infected. Antibody tests detect antibodies, not the virus, so a positive result in a baby can reflect the mother’s antibodies rather than the infant’s status. That’s why maternal antibodies can cause false-positive antibody tests in infants.

It isn’t correct to say they always interfere—interference can occur, but it isn’t guaranteed for every test or every infant. It’s also incorrect to claim they never interfere. Maternal antibodies don’t always disappear by six months; they typically wane over the first year and are usually gone by 12–18 months, but they can persist longer in some cases. Because of these factors, diagnosing HIV in infants relies on virologic tests (like HIV DNA PCR or RNA) to detect the virus itself, with antibody testing used mainly after maternal antibodies have cleared.