Risk factors for recognized and unrecognized SARS-CoV-2 infection: a seroepidemiologic analysis of the Prospective Urban Rural Epidemiology (PURE) study

• Published in: Microbiology Spectrum
• Main Author: Leong D.P.; Loeb M.; Mony P.K.; Rangarajan S.; Mushtaha M.; Miller M.S.; Dias M.; Yegorov S.; Mamatha V.; Caklili O.T.; Temizhan A.; Szuba A.; Abat M.E.M.; Mat-Nasir N.; Diaz M.L.; Khansaheb H.; Lopez-Jaramillo P.; Duong M.; Teo K.K.; Poirier P.; Oliveira G.; Avezum Á.; Yusuf S.
• Format: Article
• Language: English
• Published: American Society for Microbiology 2024
• Online Access: https://www.scopus.com/inward/record.uri?eid=2-s2.0-85184517748&doi=10.1128%2fspectrum.01492-23&partnerID=40&md5=a6b0b515a7e92b2d878310e75e52130e
• ISSN: 21650497
• DOI: 10.1128/spectrum.01492-23

There are limited data on individual risk factors for SARS-CoV-2 infection (including unrecognized infection). In this seroepidemiologic substudy of an ongoing prospective cohort study of community-dwelling adults, participants were thoroughly characterized pre-pandemic. The SARS-CoV-2 infection was ascertained by serology. Among 8,719 participants from 11 high-, middle-, and low-income countries, 3,009 (35%) were seropositive for SARS-CoV-2. Characteristics independently associated with seropositivity were younger age (odds ratio, OR; 95% confidence interval, CI, per five-year increase: 0.95; 0.91–0.98) and body mass index >25 kg/m2 (OR, 95% CI: 1.16, 1.01–1.34). Smoking (as compared with never smoking, OR, 95% CI: 0.83, 0.70–0.97) and COVID-19 vaccination (OR, 95% CI: 0.70, 0.60–0.82) were associated with a reduced risk of seropositivity. Among seropositive participants, 83% were unaware of having been infected with SARS-CoV-2. Seropositivity and a lack of awareness of infection were more common in lower-income countries. The COVID-19 vaccination reduces the risk of SARS-CoV-2 infection (including recognized and unrecognized infections). Overweight or obesity is an independent risk factor for SARS-CoV-2 infection. Infection and lack of infection awareness are more common in lower-income countries. IMPORTANCE In this large, international study, evidence of SARS-CoV-2 infection was obtained by testing blood specimens from 8,719 community-dwelling adults from 11 countries. The key findings are that (i) the large majority (83%) of community-dwelling adults from several high-, middle-, and low-income countries with blood test evidence of SARS-CoV-2 infection were unaware of this infection—especially in lower-income countries; and (ii) overweight/obesity predisposes to SARS-CoV-2 infection, while COVID-19 vaccination is associated with a reduced risk of SARS-CoV-2 infection. These observations are not attributable to other individual characteristics, highlighting the importance of the COVID-19 vaccination to prevent not only severe infection but possibly any infection. Further research is needed to understand the mechanisms by which overweight/obesity might increase the risk of SARS-CoV-2 infection. Copyright © 2024 Leong et al.