‘Hybrid immunity’ gives best Covid protection: studies

People with the "hybrid immunity" of having been both fully vaccinated and previously infected with Covid-19 have the strongest protection against the virus, two new studies said yesterday.

The studies highlighted the importance of getting jabbed for those who have natural immunity after recovering from the disease.

One of the two studies published in The Lancet Infectious Diseases medical journal analysed the health data of more than 200,000 people in 2020 and 2021 in hard-hit Brazil, which has the world's second-largest Covid death toll.

It found that for people who have already had Covid, Pfizer and AstraZeneca's vaccines offered 90 percent effectiveness against hospitalisation and death, China's CoronaVac had 81 percent and Johnson & Johnson's one-shot jab had 58 percent.

A study using Sweden's nationwide register up to October 2021 meanwhile found that people who recovered from Covid retained a high level of protection against re-infection for up to 20 months.  And people with two-vaccine-dose hybrid immunity had a further 66 percent lower risk of re-infection than those with just natural immunity.