Fabio Rojas has argued for most institutions reopening in the face of COVID-19, on the grounds that COVID mortality rates are quite low for the non-elderly.
A number of commenters on his posted legitimately raised the issue of people with serious, long-lasting complications from COVID. It’s just not a matter of a few people dying and the overwhelming majority of people recovering, but we are hearing about people who have been suffering for months from debilitating, COVID-related complications.
This raises the question, how common are these so-called COVID-19 “long-haulers”?
The CDC released a study a last week tracing the resolution of COVID-19 among people with mild symptoms–that is, who were diagnosed in out-patient clinics (rather than being diagnosed having been hospitalized for serious COVID-19 symptoms). Some media accounts [1,2,3] are linking the study to the nightmarish long-hauler phenomenon, but I am skeptical.
The CDC obtained a list of people testing positive between March 31 and June 4 from 14 academic health centers and they randomly sampled individuals within each test site. Subjects were called 2-3 weeks after their test date and interviewed about their symptoms. They were able to interview around 46% of their sample (274/582).
Among these interviewees, 35 percent said they had not returned to usual health at the time of the interview, with the rate depending on age (at most a third of those less than 50 years old still had symptoms; around half of those 50 years or older still reported dealing with symptoms). The most common symptoms failing to resolve were coughing and fatigue (43 and 35 percent of people experiencing those respective symptoms on the day of testing reported still having them at the day of the interview); fevers and chills resolved for nearly everyone experiencing those symptoms on the day of testing.
[a CNN report on this study misreported the symptom results as “for the people whose symptoms lingered, 43% said they had a cough, 35% said they felt tired…” which implies that 15% of subjects still had a cough (that is, 43% of the 35% who still felt unwell at the time of the interview). In reality, it was 26% of subjects still reporting having a cough–that is 43% of the 166 subjects reporting having a cough at the time of testing.]
It is not clear to me how serious these symptoms are; it looks like many people who had mild cases of COVID-19 were still impaired for 2-3 weeks, but I thought we already knew that having COVID-19 could mean being sick for a couple of weeks. I wish the CDC had interviewed people a bit further out from the time of a positive test result (as long-haulers say they have been sick for months). In addition, the CDC is not making the survey instrument available but the measurement of symptoms seems binary and does not capture the debilitating nature of the long-hauler symptoms.
I would also guess that the study’s estimates of the prevalence of long-lasting symptoms are upwardly biased, as people with mild forms of COVID-19 are probably (a) less likely to get tested and (b) less likely to have enduring symptoms. I suspect, but I don’t really know, that people with long-lasting symptoms are also more likely to agree to an interview request from health researchers (although if they are really sick they may not; the researchers excluded nine subjects because a proxy did the interview and I wonder if that was because they felt too unwell to talk with an interviewer).
Having said that, I do not endorse arguments for re-opening, or even qualified ones calling for re-opening for the non-elderly while keeping the elderly locked down (I am not even sure what that would look like, much less work). While I suspect long-hauler cases are rare, we just do not know enough about the disease to let it burn through the population (even the non-elderly population).