In individuals over age 65, infection with COVID-19 confers only partial protection from reinfection with the coronavirus, according to a new study in Denmark, reported in The Lancet. In a study of 11,068 individuals infected during the first COVID-19 wave, the previous infection cut the rate of reinfections by 80% among people under age 65, but only 47% among those over age 65. The researchers point out that, given that older people are at particular risk for COVID-19 mortality, additional protections remain essential, even for those who have already had the illness. While a coronavirus infection is only limited assurance against reinfection, vaccines are much more consistent in their ability to prevent infections. In addition, dietary improvements, particularly a low-fat, plant-based diet, remain the cornerstone for managing the underlying risk factors—obesity, diabetes, and hypertension, in particular—that make COVID-19 especially deadly.
Hansen CH, Michlmayr D, Gubbels SM, Mølbak K, Ethelberg S. Assessment of protection against reinfection with SARS-CoV-2 among 4 million PCR-tested individuals in Denmark in 2020: a population-level observational study. Lancet. Published Online March 17, 2021. https://doi.org/10.1016/S0140-6736(21)00575-4