
Infection with COVID-19 may offer protection against other, less severe endemic coronaviruses (eCOVs) that are often behind the common cold, according to a study today in Science Translational Medicine. COVID vaccines, however, don't appear to afford similar protection.
Three coronaviruses can cause severe and fatal disease in humans: MERS-CoV, SARS, and SARS-CoV-2. But four eCOVs typically cause symptomatic, mild respiratory illnesses, accounting for 15% to 30% of "common colds."
The study was based on polymerase chain reaction test results from a retrospective cohort of 4,935 people who presented for clinical evaluation for respiratory illness from November 2020 to October 2021 at Boston Medical Center.
Half the risk of symptomatic colds
Participants were grouped into three categories: previous COVID-19 infection (501 participants), previous COVID-19 vaccine but no known infection (1,565), and no SARS-CoV-2 antigen exposures (no prior infection or vaccination; 2,869).
"Incidence of symptomatic eCoV infection was significantly lower in those with prior SARS-CoV-2 infection and no vaccination (2 of 275, 0.7%) as compared with the individuals who had been deemed fully vaccinated but had no known prior SARS-CoV-2 infection (44 of 1,463, 3.0%)," the authors wrote.
Incidence of symptomatic eCoV infection was significantly lower in those with prior SARS-CoV-2 infection and no vaccination
Previous COVID-19 infection was associated with an almost 50% reduced risk of a future symptomatic eCoV during the follow-up period of more than 120 days [hazard ratio 0.48, 95% confidence interval 0.21 to 1.1).
"Our observations have important implications for future pan-CoV vaccines and other disease prevention strategies," the authors concluded.