Back

1st, 2nd, and 3rd+ SARS-CoV-2 infections: associations of prior infections with protection and severity

Maier, H. E.; Ojeda, S.; Shotwell, A.; Lopez, R.; Sanchez, N.; Saborio, S.; Plazaola, M.; Barilla, C.; Kuan, G.; Balmaseda, A.; Gordon, A.

2025-04-08 epidemiology
10.1101/2025.04.07.25324191 medRxiv
Show abstract

Since the emergence of the antigenically distinct Omicron variant, SARS-CoV-2 reinfections have increased and are common. Yet, as we approach endemicity, the frequency, severity, and consequences of reinfections remain poorly understood. Using data from a household transmission study in Managua, Nicaragua (2020-2024), we evaluated protection conferred by one, two, and three+ prior infections and compared the severity of first, second, and third+ RT-PCR-confirmed SARS-CoV-2 infections. In adults, compared to those with no prior infections, after adjusting for vaccination, one, two, and three+ prior infections were associated with increasing protection from symptomatic infection: 46%, (95% Confidence Interval [CI]: 32-57%), 69% (95%CI: 56-78%), and 77% (95%CI: 58-88%), respectively. Compared to first infections, second and third+ infections were associated with decreasing severity in adults, adjusted for vaccination; 35% (95%CI: 11-52%) and 42% (95%CI: 6-65%) less moderate/severe disease, and 152% (95%CI: 46-336%) and 243% (95%CI: 82-545%) more subclinical disease, respectively.

Matching journals

The top 7 journals account for 50% of the predicted probability mass.

50% of probability mass above

"Similar papers" are the closest papers from that journal in the model's embedding space. They show what the match is built on, but the ranking comes mostly from a classifier over the whole training set, not from these examples alone.