https://www.israelnationalnews.com/News/News.aspx/310963
A new study on the effects of natural infection by the coronavirus suggests that there may be little to no benefit for recovered SARS-CoV-2 patients in receiving vaccines against the coronavirus.
According to the study, conducted in Cleveland, Ohio and published in the MedRxiv journal last month, people who were infected with the coronavirus enjoy significant long-term immunity from the virus, which is unlikely to be increased by being injected with one of the coronavirus vaccinations now on the market.
The study followed 52,238 employees of the Cleveland Clinic Health
System, monitoring infections among vaccinated and unvaccinated workers,
and the incidents of reinfection among both vaccinated and unvaccinated
workers.
"The cumulative incidence of SARS-CoV-2 infection among previously infected unvaccinated subjects did not differ from that of previously infected subjects who were vaccinated, and that of previously uninfected subjects who were vaccinated."
ReplyDeleteWhen you don't power a study sufficiently to tease out a difference between groups that all have extremely low attack rates, you cannot make sweeping conclusions. An elderly person should not trust this result as the n was too small and the previously-infected group trended very young. Pfizer's trial also had around 2000 previously-infected, and when including all measures inclusive of "medical history" of sars cov2 (which includes people infected before there was testing in the US), the cases were 13 in vaccinated and 17 in placebo. Likewise, too small numbers to be statistically significant in either direction.
But clearly there were some cases among the previously infected, even from among a small sample size of around ~2000, in Pfizer's trial, followed for only a few months. So this study, examining young medical workers with full PPE gear showing 0 such reinfections cannot be assumed as the real number. With a larger sample, and in a real world setting, you'd obviously have above 0. The question whether they'll be helped by vaccination remains unanswered however plausible it may seem that they would be.
Cleveland Clinic's desire to see doses spared and sent to other countries rather than being used to vaccinate people already infected, is admirable but moot. The early demand for vaccination has already been met in the US, and there is a surplus even if you vaccinated every single person previously infected with Covid, plus every single never infected person.
They argue something 5 months too late with a study that could only have been completed in the 5 months since. This sort of thing never makes much sense.
One study of many. Others show that natural immunity is temporary and not as strong as that conveyed by the vaccine so vaccination is still recommended.
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