Treating HIV-positive infants with an aggressive regimen of antiretrovirals (ARVs) shortly after birth can greatly reduce the establishment of the viral reservoir. Canadian researchers studied 136 babies who began ARVs within 72 hours of birth because they were at high risk of contracting HIV from their mothers. The researchers followed up with the children when they were between 2.5 and 7.5 years old. Twelve of them had been infected with HIV, and out of that group four had a sustained undetectable viral load. Those four all received treatment within 24 hours of birth and had fully suppressed the virus between 66 and 189 days after birth. All four tested negative for HIV with standard antibody tests. Even an ultra-sensitive test could not detect any viral load in their bodies at the follow-up point. Evidence of a viral reservoir in HIV’s various hiding places was scarce, although low levels of cell-associated HIV RNA were detected in all the children, and one child had a tiny amount of detectable virus that was capable of replicating.