The role of respiratory co-infection with influenza or respiratory
syncytial virus in the clinical severity of COVID-19 patients: a
systematic review and meta-analysis
Abstract
Aim: To understand the impact of influenza/RSV co-infection on clinical
disease severity among COVID-19 patients. Methods: We conducted a
systematic literature review of publications comparing the clinical
severity between the co-infection group (i.e., influenza/RSV with
SARS-CoV-2) and mono-infection group (i.e., SARS-CoV-2), using the
following four outcomes: need or use of supplemental oxygen, intensive
care unit (ICU) admission, mechanical ventilation and deaths. We
summarized the results by clinical outcome and conducted random-effect
meta-analyses, where applicable. Results: Twelve studies reporting a
total of 7862 COVID-19 patients were included in the review. Influenza
and SARS-CoV-2 co-infection was found to be associated with a higher
risk of ICU admission (5 studies, OR: 2.09, 95% CI: 1.64-2.68) and
mechanical ventilation (5 studies, OR: 2.31, 95% CI: 1.10-4.85). No
significant association was found between influenza co-infection and
need/use of supplemental oxygen or deaths among COVID-19 patients (4
studies, OR: 1.04, 95% CI: 0.37-2.95; 11 studies, OR: 1.41, 95% CI:
0.65-3.08, respectively). For RSV co-infection, data were only
sufficient to allow for analyses for the outcome of deaths, and no
significant association was found between RSV co-infection and deaths
among COVID-19 patients (3 studies, OR: 5.27, 95% CI: 0.58-47.87).
Conclusions: Existing evidence suggests that co-infection with influenza
might be associated with a 2-fold increase in the risk for ICU admission
and for mechanical ventilation among COVID-19 patients whereas evidence
is limited on the role of RSV co-infection. Co-infection with influenza
does not increase the risk of death in COVID-19 patients.