I don’t think this paper is a great source for that idea - the ratio of people with one infection (440,000) to people with three or more infections (1,000) is so different that I wonder if demographics or behavioral characteristics differ between the groups.
Empirically, their conclusion can’t really be true or each COVID-wave would be worse than the preceding one
Unless that damage that is accumulating doesn't lead to immediate visible effect but delayed worse outcomes, eg. early death via heart failure or stroke, long-term slightly reduced IQ, mildly worse blood circulation leading to subtle sexual dysfunction etc.
The linked paper says, "Compared to no reinfection, reinfection contributed additional risks of death [...], hospitalization [...] and sequelae [...]".
I need to read the full paper when I have more time, but it does not seem to be dealing with symptoms? And the sequelae seem most troubling since those could take a long time to manifest.
You’re reading that paper wrong. It says that the cumulative risk of death, long Covid, etc increases with the number of infections. Of course it does: the only was it wouldn’t would be if reinfections has zero or negative risk.
(I’m ignoring whether the paper is correct in the first place.)
I’m not sure what you think I’m saying wrong. Here is the salient quote from the abstract
“The evidence shows that reinfection further increases risks of death, hospitalization and sequelae in multiple organ systems in the acute and postacute phase.”
Or, as a more dramatic example, suppose infection #1 gives a 50% of long Covid. Infection #2, in a patient without long Covid, gives a 1% risk of long Covid. Your cumulative risk of long Covid after 2 infections is 50.5%, which is greater than 50%.
