In recent studies that assess positive case numbers based on wether they have or have not been vaccinated for covid… Do any studies of current cases/hospitalizations ever track the non vaccinated with previous Covid infection who are experiencing a second/subsequent infection? I have yet to come across info on percent positivity in this subset of unvaccinated people (yet previously infected) who get Covid.
According to CNN the reinfection rate is very high. Fox says it is very low. MSNBC indicates the unvaccinated are doing Satan’s work while Breitbart indicates MSNBC is in fact run by Satan.
Hope this helps.
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The numbers (and I wouldn’t call it a study) would only be for those hospitalized. They aren’t keeping numbers for those with infections, with or without vaccinations, for those who have covid but aren’t hospitalized. Some doctors may report to their state health departments but I don’t believe there is any obligation to do so.
By most accounts, the fully vaccinated have greater immunity than those who were previously infected. The infection rate for the fully vaccinated depends on how much (or little) you’re exposed to the delta variant. If you aren’t exposed, your chance of infection is zero. If you’re exposed to large quantities of the new virus, your chance of infection, even with full vaccination, could be greater than 30%. For those with previous infection, I’d expect the reinfection rate, if they were unvaccinated but previously infected, to be greater than the infection rate of the vaccinated.
I hear from people who are vaccine reluctant that they won’t get vaccinated because they already have “natural immunity”. And on the flip side, expectations that fully vaccinated have better immunity than those previously infected. But this is speculation on both sides! It doesn’t seem like it would be that difficult to track the reinfection rate of these people, even tracking reinfection after first infection was clinically mild, moderate, or severe. It’s possible some of these people would get vaccinated if the data refutes their position that a previous infection conveys enough protection… we might get more shots in arms if the studies gave us a better understanding of the entire landscape.
I think this is difficult data to obtain. For example, my elderly father had COVID spring 2020. He was still testing positive (in between negative tests) 9 months later. When he had an antigen test (after getting his 2 vaccines), the nurse said - wow he has a lot of antigens! I highly doubt my father was reinfected the 3-4 times he tested positive over that period of time, more likely he had lingering viral traces in his body.
So how do you measure reinfection vs. still having some traces of the virus, in the short period of time we have been testing for this virus?
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I’m glad to hear your elderly father survived his bout with covid! Did he ever have recurrence of clinical symptoms, either before or after his vaccine sequence?
To clarify, the data I’d like to see would be from the current population with severe disease/hospitalization who are unvaccinated… what percent are first time infections (no previous Covid symptoms or diagnosis), vs what percent have previously been diagnosed with covid but are now hospitalized and struggling with covid symptoms/disease. Of the latter group… were they previously asymptomatic positives or did they have symptomatic disease? It would be interesting if they could find statistically significant information regarding reinfection with severe disease, and how much it would have to do with severity of previous disease. All I ever read about is speculation- but no actual studies/conclusions!
He was hospitalized the first time he had it. What would be considered a mild case - treated with steroids and low level oxygen. His iniital hospital stay was extended because it took several weeks to get a negative COVID test (which was required for him to return to his assisted living facility). He landed in the hospital a few more times over the past year, due to breathing difficulties, he has lung damage from the COVID as well as from years of smoking. He has actually been better since the vaccine (no new breathing issues, although he now requires oxygen all the time). Despite having positive COVID tests (performed routinely at his assisted living as well as during his hospital stays), he has never had symptoms again.
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This study covering June 2020 to January 2021 (mostly pre-vaccine and obviously pre-Delta) found that COVID-19 was 84% protective against subsequent COVID-19 and 93% protective against subsequent symptomatic COVID-19.
https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(21)00675-9/fulltext
This study covering December 2019 to November 2020 found that under 1% of those who got severe COVID-19 got reinfected with COVID-19 later.
However, the immunization effect of previous COVID-19 with older variants may be somewhat weaker against Delta, similar to the immunization effect of vaccination against the ancestral virus.
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https://www.nejm.org/doi/full/10.1056/NEJMc2101927 includes this graphic:
Section B shows that, pre-vaccination, those with history of COVID-19 had widely varying antibody responses (blue and green dots on the"Baseline" graph), comparable to the antibody responses after first dose vaccination for those without prior history (brown dots on the “Wk 3” graph). After first dose vaccination, those with history of COVID-19 had uniformly high antibody respnses, except for one unlucky person (blue and green dots on the “Wk 3” graph).
Thanks, @ucbalumnus, this is great information!
Here’s an article from the CDC
Not sure if it’s already been pasted here
A blurb about the article
NEW @CDCgov study shows that people who have contracted COVID-19 before are more than 2X as likely to be reinfected if they are not fully vaccinated, compared to those who are.
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