A confound this study doesn't really get into is that not everyone seroconverts (so "antibody test negative but still reports symptoms" doesn't _have_ to be a false positive), but nocebo effects are nevertheless very real, and not just for covid.
In the area of "lingering aftereffects", I see a lot of affinities between covid and lyme disease: both usually don't have long aftereffects, both can cause some serious aftereffects that take a long time to go away; both also have a population of people who have real and persistent negative health consequences that were not caused by the initial pathogen but are attributed to that pathogen by the person who has them.
The third group is the most troublesome, because they require both compassionate recognition of their subjective suffering and also a clinical decoupling between that suffering and its ostensible cause, and that's a hard thing to do well.
In the area of "lingering aftereffects", I see a lot of affinities between covid and lyme disease: both usually don't have long aftereffects, both can cause some serious aftereffects that take a long time to go away; both also have a population of people who have real and persistent negative health consequences that were not caused by the initial pathogen but are attributed to that pathogen by the person who has them.
The third group is the most troublesome, because they require both compassionate recognition of their subjective suffering and also a clinical decoupling between that suffering and its ostensible cause, and that's a hard thing to do well.