OBJECTIVES: Coinfections in COVID-19 patients have been found to exacerbate clinical outcomes and increase mortality risk. Given the changes in COVID-19 wave from its inception to 2022, investigating coinfections among COVID-19 patients is crucial. This study aimed to compare coinfections prevalence in COVID-19 patients from Dec 2019-May 2021 (early pandemic) and Jun 2021-Dec 2022 (late pandemic) and evaluate its impact on hospitalization and mortality.

METHODS: Research articles (systematic reviews and observational studies) were retrieved from PubMed, WHO COVID-19 database, and Google Scholar based on relevant search terms, using MaiA automation platform. JBI’s CoCoPop framework was used for study selection. Studies evaluating coinfections and not secondary or superinfections were included. Data on patient demographics, coinfection(s) prevalence, pathogens involved, hospitalization and mortality rate were extracted. The findings were summarized descriptively. Study protocol registered prospectively on PROSPERO: CRD42023431604.

RESULTS: Among 2486 retrieved articles, we included 74 eligible studies (12 prospective, 42 retrospective, and 20 systematic reviews). Overall, coinfections prevalence ranged from 0.12%-60%. During early pandemic period, coinfections rate ranged from 0.12%-60% whereas it was 0.4%-38.8% in late pandemic. Hospital length of stay (LOS) and ICU admissions differed between two periods (LOS: 7-44 days and 5-20 days; ICU admissions: 8.4%-100% and 14.1%-55% in early and late pandemic periods, respectively). The highest mortality rate was 87% in early pandemic which declined to 67% in late pandemic period.

CONCLUSIONS: The late pandemic period demonstrated lower coinfections prevalence, which can be attributed to effective vaccination and improved diagnostic and management approaches. This had domino’s effect on mortality and hospitalization with higher prevalence between 2019-2021. However, for future interpretation, a causal relationship between hospitalization and/or mortality rate and coinfections should be established. These findings can serve as precursor for large-scale studies aiming to assess long-COVID effect on co-infections. Further, rigorous antibiotic stewardship programs assessing coinfections prevalence is recommended.