So-called "viral load” tests are tests for viral particles in the blood. The blood (serum) contains only a small part of the virus in an infected person’s body, but it is that part which is damaging (active). The rest of the virus hides in “viral reservoirs” in the central nervous system and elsewhere. ARVs have the wonderful effect of eliminating (or at least, massively reducing) viral particles from the blood. But they don’t cross the blood-brain barrier. The virus lurks in the central nervous system, and if a person stops taking his ARVs, it rushes out of the viral reservoirs and back into the blood, and eventually the virus in the blood returns to its previous level. That is why it is so important for people taking ARVs to keep up medication.
ARVs have saved millions of lives, and in the developed world, they work, pretty much. Sometimes there are side effects. These can be horrid, but with the latest ARVs are generally manageable. Some people don’t like the effects that they have on weight distribution - fattening tummies and making legs skinnier - but hey, you are alive.
Here, the challenges are altogether different. ARVs have tended to be given out in 2-week batches. So every two weeks you have to go to the clinic to get more. And that isn’t so easy here. There is not much public transport. Without a car, it takes ages to get around. A lot of walking gets done. And that is hard if one is sick. One of the orphanages we visited described regular treks with scores of little children walking for hours to go to the clinic to get their meds. Then there is food - some ARVs need to be taken with food, and the side effects if you don’t eat are pretty awful. Here, with poverty, many people just don’t have enough to eat. Without food, many don’t take the drugs, and so the virus re-enters their blood, white blood cells die, and the virus mutates, so that the ARV regimen no longer works effectively. There is a lack of doctors to review & change regimens, and a limited choice of ARVs, so people get sicker and eventually succumb to disease. Typically, TB. That is why average life expectancy in Africa after diagnosis, even with ARVs, is so low.
That was a digression I was talking about viral load tests. An electro-magnetic field isn’t affected by the blood-brain barrier, and whatever effects it has apply to the whole body. And it can’t remove the virus or eliminate it from blood. A virus may be damaged and/or inactive, but its particles are still there to show up in a “”viral load“ test (unless the person is taking ARVs). Once a virus is no longer active, viral particles are naturally slowly eliminated. One HIV specialist doctor told me that it would take 27 years to entirely eliminate the HIV virus, if it became inactive. I have no idea where that came from.
As for ordinary CD4 test, those measure the total number of CD4 cells in the serum. These are a type of lymphocyte, or white blood cell, part of our immune defence system, and the cell which is most quickly affected by HIV. The ordinary test does not distinguish between viable CD4 cells and those which are dying, so it is a bit crude. According to the standard test, a CD4 count of 500 looks better than one of 475, but if only 400/500 cells are viable and 20% of cells are dying or dead, it may well not be.
And a liver function test evaluates how well the liver is doing with the effects of medication. If the liver is suffering, it may be time to change the drug regime.
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