Previous COVID infection boosts long-term immunity and reduces the risk of hospitalization and death to the same level as vaccination, new peer-reviewed research shows.
The study, led by the University of Washington and published by the medical journal The Lancet, is said to be the “most comprehensive study to date” of the impact of natural immunity on the disease.
“For people who are already infected Coronavirus disease At least until then, natural immunity to severe disease (hospitalization and death) against all variants was strong and durable (88% or higher at 10 months post-infection),” the researchers said.
but caught early Variant found to offer reduced immune protection against reinfection with more transmissible virus Omicronand 36% after 10 months.
The research was partly carried out by Bill & Melinda Gates Foundationincluding 65 other studies from 19 countries looking specifically at those who hadn’t been vaccinated.
This suggests a level and duration of protection against reinfection, symptoms and severe disease that is at least comparable to that provided by two doses of mRNA vaccines such as Pfizer and Moderna.
The researchers also found that after an analysis of 21 other timescale studies, the protection rate was about 85% in the first month, dropping to 79% by month 10.
Based on five studies reporting severe illness (hospitalization and death), they did find overall that the overall protection rate remained high at 10 months – 90% protection for the original strain, Alpha and Delta strains, protection for Omicron The rate is 88%.
China’s COVID surge yields no new variants
Most long-term COVID patients develop organ damage after a year
Lead author Dr Stephen Lim stresses that vaccines remain the safest way to protect yourself, as “acquisition of natural immunity must be weighed against the risk of severe disease and death associated with primary infection”.
Co-author Dr Caroline Stein added: “Vaccines are still important for everyone to protect at-risk groups such as those over 60 and those with comorbidities.
“This also includes previously uninfected and unvaccinated populations, as well as people who were infected or had their last dose of vaccine more than six months ago.
“Policymakers should consider both natural immunity and vaccination status to gain a comprehensive picture of an individual’s immune status.”