Reflections on HIV

My post yesterday on the lunkhead senator from Wisconsin inspired some thoughts about Human Immunodeficiency Virus (HIV) and the disease it causes, called Acquired Immunodeficiency Syndrome or AIDS. The syndrome got its name before the viral cause was discovered, which is why it's called a syndrome, the word for a collection of symptoms when the cause is unknown or unspecified. It might be better to call the disease simply HIV disease, as it can have symptoms other than immunodeficiency, and many people nowadays do just that.

 

I spent much of my career in public health, and then in academic research, focusing on HIV.  When I first started working in public health, the virus had been discovered, but there was no effective treatment. We did know how it was transmitted, however, which meant there were public measures we could take to prevent it. A major problem, however, was that most transmission in the U.S. was happening among people who endured moral condemnation -- gay men and injection drug users. These weren't, and aren't, the only people at risk but that's where the disease was first recognized. This meant that the Republican president, a dimwitted B movie actor named Ronald Reagan, didn't care about it. In fact for years he never even mentioned it. His successor George Bush I didn't care about it either. A lot of people died because of neglect, but also because of active political opposition to effective public health measures. Remind you of anything?

I am continually surprised by how many people still don't know basic facts about HIV. Like Covid-19, it's an RNA virus, but unlike Covid, it's also a retrovirus. That means the viral genome is transcribed into the nuclear DNA of infected cells, and it can just sit there indefinitely until the viral DNA is activated, which means the immune system can't find it and it's impossible to eradicate. Once you're infected, it's for life. The immune system can find HIV particles in the blood, and recognize cells that are actively producing virus, but the virus is still elusive because its antigenic proteins are hidden by sugar. This is a major reason why no effective vaccine has been developed.

HIV preferentially infects immune system cells called helper T cells. The immune system can suppress it for a time, usually several years, but it gradually depletes the T cells and then you get AIDS, which means your immune system doesn't work well and microbes that are always around and don't normally cause disease start making you sick. Then you waste away and die. Before that, however, you may have been infected for as long as 10 years without knowing it. That can be bad news for other people who might have caught it from you, but that can only happen if a sample of your bodily fluids gets into another person's blood stream. That can happen through sex, sharing injection equipment, medical transfusion of blood or blood products, or by accident if someone somehow comes into contact with your blood. Pregnant women can also transmit it to their babies. 

We're pretty sure that HIV originated in monkeys in Africa. Long before AIDS was first recognized, which happened to be in the U.S., the virus was present in Africa. Most likely a hunter acquired it by butchering a monkey. That could have happened more than once as wild animals are commonly consumed in remote parts of Africa, but nobody noticed because rural Africans have a lot of other infectious disease problems, including malaria and tuberculosis, which can cause wasting and would likely kill an immunosuppressed person without anyone suspecting that anything else was going on.

So you now have an understanding of the moving parts:

• An infection that people can harbor for years without knowing it, but which is ultimately fatal, and it's a really terrible death by the way.
• An infection that mostly affects stigmatized people.
• An infection that is not transmitted by causal contact, or even intimate contact short of sexual intercourse or needle sharing.

The result was a kind of natural social and medical experiment that revealed a whole lot about society, culture, and humanity, as well as spurring a vast increase in understanding of the relevant biology. I'll put the parts in motion next time.