I wanted to discuss one episode in which Heather suggests she may have gotten COVID-19. She recalls being very sick and having a litany of symptoms, some of which were consistent with the new virus. But the illness was in early February, before anyone was even talking about the virus being present in the US. She didn't even think that it might have been COVID-19 until much later. We recently learned that the virus was probably in the U.S. much earlier than the first reported cases some time in late February or early March, so that opened up the possibility. She describes at first being very tired and coughing a lot. She had no energy to do anything and cancelled a lot of plans so she could stay home and rest. Then she describes experiencing (paraphrasing, not an actual quote here):
a step-function improvement in my health in the space of a few minutes while taking a shower. I decided I would join Bret for a dinner with some friends that evening. Everything was fine until I was at the restaurant and began coughing uncontrollably.My immediate thought was, "Whoa! What a sneaky and brilliant strategy for a virus to reproduce itself!" Of course viruses aren't really sentient or intelligent and aren't deliberately forming a strategy to jump to new hosts. But the ones who are effective at propagating themselves look as though they are following a strategy. There are plenty of examples of parasites hijacking their hosts and changing their behavior to make the parasite more successful. Toxoplasmosis famously makes mice fearless of cats (sexually attracted to cat urine, in some tellings), which allows it to continue its life cycle. There is a fungus that hijacks the tiny brains of their ant hosts. The virus Heather Heying experienced first compelled her to stay at home and rest. It got her to conserve energy, presumably giving the virus more resources to spend on its own reproduction. It then "let up", allowing her to feel good enough to go out in public. Whether it just "let up" in the sense of ceasing to attack her cells or perhaps hijacked her to make her feel better (release of adrenaline? some other mechanism? is this biologically plausible?), it convinced her she could get out of bed. Once she was among people, she felt sick and started coughing, which is the virus's strategy for getting to new bodies. She describes regretting that she may have infected several other people at the restaurant. Again, it's not clear that this was COVID-19. From the early timing and her description of the symptoms, this seems unlikely. But it's an interesting anecdote. Does the virus she had hijack people's behavior at the neurological level by literally monkeying with neurotransmitters? Or does it accomplish this in a more boring way by simply "making you feel sick"? Is it responding to environmental cues somehow? Or it is simply on some kind of natural timer? Did the virus really make her feel a "step function improvement" in her well-being? Or was it just the effect of a hot shower? Was she misremembering events from a few months ago? Real or not, it's an intriguing possibility.
In a recent post, I suggested that viruses that refrain from killing or incapacitating their hosts will be better at spreading. They will have "longer legs", so to speak. Heather Heying's anecdote suggested that this might not always be the case. If a virus hits upon this strategy of starting and stopping, temporarily fooling the host into thinking they are better, then they could be quite deadly and still be very good at spreading. COVID-19 hit upon a different strategy; it seems to have a very wide distribution of severities, with a lot of asymptomatic and mild cases in the left tail and a relatively high rate of hospitalizations and death in the right tail. That could also mean it's unlikely to mutate to become less deadly.
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