A new study suggests the vaccine can provide a great benefit to those who have had Covid-19.
The research examined an incident where the Delta variant tore through a Texas prison, infecting three quarters of the incarcerated people there. Nearly 80% of those infected were fully vaccinated, most with the Pfizer shots.
But while the new study shows that breakthrough cases can absolutely happen in high-risk settings like prisons and jails – where it’s often impossible to maintain physical distance and where proper ventilation is a major concern – it also contained some good news.
First, the Covid-19 vaccines largely prevented severe illness, even in the face of Delta. Four of the 172 people who caught the coronavirus were hospitalised during the outbreak. Three were unvaccinated.
And by far the lowest attack rate was among fully vaccinated people who’d also been previously infected with Covid-19 – “highlighting the importance of vaccination, even among persons with previous infection,” argued the authors of the study, published by the US Centers for Disease Control and Prevention.
One limitation of the study is that the pool of people who had been infected with Covid-19 and who also had been vaccinated was relatively small.
Still, the research offers more evidence that the fully vaccinated have a high degree of protection against hospitalisation or death – even in really high-transmission settings and even in the face of the Delta variant, which is about twice as contagious as previous variants.
And it adds to a growing body of evidence suggesting that people who have had and recovered from Covid-19 – and who have been vaccinated – are likely the safest of all.
Why vaccines are recommended even if you’ve had COVID-19
Some people, including former US vice presidential candidate Sarah Palin, have argued against vaccination for those who’ve been infected, saying that “natural” immunity is safer and possibly stronger. They’ve pointed to a study in Israel that suggested the strength of natural immunity.
But that study was not subject to peer review, and it has been widely shared on social media with parts of its findings omitted – namely, that immunity was higher among people who got a dose of the Pfizer vaccine.
In fact, the Centers for Disease Control and Prevention has been saying for months that people who have had Covid-19 and recovered should still get vaccinated, in part because researchers still don’t know how long natural immunity lasts (though if you received certain treatments, like monoclonal antibodies, you should wait three months before you get the shot).
Additionally, prior studies have shown that, among people who get Covid-19 and recover, those who do not get vaccinated are more than twice as likely to get Covid-19 again when compared with those who are fully vaccinated.
All of which goes to show: Getting vaccinated is important, even if you’ve already had Covid-19.
And while vaccination does an excellent job of keeping people out of the hospital, it doesn’t stop the virus’s spread altogether. Mitigation strategies like masking, social distancing, hand-washing and improving ventilation continue to be necessary to contain the virus, especially in high-risk settings.
Experts are still learning about Covid-19. The information in this story is what was known or available at the time of publication, but guidance could change as scientists discover more about the virus. To keep up to date with health advice and cases in your area, visit gov.uk/coronavirus and nhs.uk.