Just How Much Protection Against SARS-CoV-2 Reinfection Does Prior Infection Provide?

摘要

Risk for reinfection with SARS-CoV-2 following natural infection remains incompletely characterized. Now, two large observational studies address this question.In the first study, investigators used data from U.S. commercial laboratories and linked claims. Among >3 million patients with SARS-CoV-2 serologic tests, 11.6% had positive index results. Among those who were initially seronegative, the rate of subsequent positive PCR tests during a median 47 days of follow-up consistently ranged from 3% to 4%. In the sero-positive group, the rate of positive PCR tests declined from 11.3% (0-30 days) to 0.3% (>90 days). The ratio of positive PCR tests in the seropositive vs. seronegative groups had declined from 2.8 to 0.10 when measured 90 days after index serology.