A study published at the New England Journal of Medicine showed that reinfections of COVID had 90 percent lower odds of resulting in hospitalizations or death than primary infections.
The study revealed few confirmed reinfections among 353,326 people who got COVID in Qatar. The country had its first wave of infections from March through June 2020. Forty percent of the population had detectable antibodies against SARS-CoV-2.
From January through May 2021 the country had a pair of waves due to the Alpha and Beta variants.
The study excluded 87,547 people with a vaccination record.
There were 1,304 identified reinfections. For those reinfected, the median time between first infection and reinfection was 277 days.
“The odds of severe disease at reinfection were 0.12 times that at primary infection,” the study said. “There were no cases of critical disease at reinfection and 28 cases at primary infection, for an odds ratio of 0.00. There were no cases of death from COVID-19 at reinfection and seven cases at primary infection.”
Four reinfections results in acute care hospitalization. None led to hospitalization in an ICU. None resulted in death.
“Reinfections were rare and were generally mild,” the study said. “Perhaps because of the primed immune system after primary infection.”