Study: recovery from Covid-19 gives more immunity than Pfizer

A new study appears to contradict previous data about the efficacy of vaccines, claiming that those who have recovered from Covid-19 previously have more immunity from the Delta variant than those who are fully vaccinated with the Pfizer and BioNTech vaccines.

Conducted by Israeli researchers, it is the largest real-world study that compares the natural immunity people get from having recovered from Covid-19 to the safety provided by the Pfizer vaccine. And while previous studies showed that previously having Covid-19 provided decent immunity from reinfection, but not as much as vaccines, this new research seems to suggest otherwise.

One big difference that may explain the report seeming to conclude the exact opposite of other studies: previous research was not compared with the Delta variant of Covid-19.

The new study shows that people with 2 Pfizer-BioNTech vaccines are 6 times more likely to catch the Delta variant of Covid-19 than those who have recovered from Covid-19 previously. It also showed that those vaccinated are 7 times more likely to have symptomatic infections versus those who had Covid-19 previously.

But the research did show that, like vaccines, natural immunity decreases over time. That 6 times figure for reinfection jumps to 13 times higher for vaccinated people compared to people who had Covid-19 in 2021 versus in 2020.

These findings would suggest a blow to the idea that vaccination is a definite solution to the Covid-19 pandemic while giving a boost to those who advocate for allowing Covid-19 to run its natural course through the world population allowing for natural immunity and eventually herd immunity.

Preliminary research also suggests that a booster vaccine appears to prolong and strengthen protection for those who have already recovered from a previous Covid-19 infection, though with booster shots only just getting underway in a select few countries, Israel included, the long-term effects or benefits of the extra shots can not yet be determined.

The study has not yet been thoroughly peer-reviewed, but the preprint data was recently published in medRxiv, a website that posts unpublished research papers in the field of medicine, clinical research, and related health sciences.

SOURCE: Bloomberg