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There's a story going round the news about a baby that was, apparently, cured of HIV using a cocktail of drugs at an early age. The story piqued my interest, but details seem scarce. One of the main things I've seen being refuted about it is the difficulty in proving that (a) the child actually had HIV in the first place, and (b) that the child is really fully cured.

I've seen the following arguments:

  • Western Blot tests on young children are practically useless, since they test for antibodies. The child will likely have antibodies passed down by the HIV+ mother, regardless of whether the child has HIV. The test will show the antibodies, which may be mistaken for an active immune response from the child. As such, there will be a high false-positive rate on such tests.
  • Using PCR to attempt to identify a lack of HIV is flawed, since it may lay dormant in a small colony of T-cells until a secondary immune response is triggered, causing a new outbreak. As such, it is very difficult to show that a patient is "cured".

Are these arguments valid? Are there any other reasons to be sceptical about the claims? Any other information that might be useful in understanding the case?

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Western Blot tests on young children are practically useless, since they test for antibodies. The child will likely have antibodies passed down by the HIV+ mother, regardless of whether the child has HIV. The test will show the antibodies, which may be mistaken for an active immune response from the child. As such, there will be a high false-positive rate on such tests.

The mother's T-cells are in the fetus anyways (15/18 Fetal lymph nodes contained T-reg cells). If the mother is infected and left untreated (as was the case with the Mississippi child), then the viral load is going to be high. The chances of it passing to the fetus are going to be high as a result.

Using PCR to attempt to identify a lack of HIV is flawed, since it may lay dormant in a small colony of T-cells until a secondary immune response is triggered, causing a new outbreak. As such, it is very difficult to show that a patient is "cured".

"Flawed" is the wrong word. The argument is built into the tests. The child was functionally cured - which means below detectable levels instead of "completely nonexistent within the body." Yes, it's entirely possible that the HIV is hiding somewhere in the body and could make a reappearance, but at the moment it's not showing any significant titer in the blood.

I don't think there's been a test developed that can assess the entire body to find the lone viral capsid left.

However - that isn't to say that the "cure" has been found. So far it's a single person cured this way. One. That makes it a case study, not a therapy, treatment, vaccine, or even reasonable assessment that it's possible to do again.

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The one that actually makes me skeptical of the use of this is that this "cure" was primarily a massive dose of antiretrovirals used as catchup therapy because the infant's mother didn't have access to prophylactic treatments while she was pregnant and delivering.

Basically, it's a cure that requires you to have access to antivirals very, very near the beginning of infection, and is largely a solution to a problem that is "solved" in the developed world (maternal transmission of HIV is very rare).

It's not a cure that can be extended to the settings where a cure is most desperately needed. So while an excellent proof-of-concept, and a safety net for when someone is poorly served by the medical system? Sure, this is amazing. As some watershed moment in HIV research? Less convinced.

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