Interactions between SARS-CoV-2 and Influenza and the impact of coinfection on disease severity: A test negative design

Study suggests that cocirculation of these viruses could have a significant impact on morbidity, mortality and health service demand, thus testing for influenza alongside SARS-CoV-2 and maximising influenza vaccine uptake should be prioritised to mitigate these risks.

SPS commentary:

Individuals tested for influenza and SARS-CoV-2 were extracted from national surveillance systems between 20/01/2020 and 25/04/2020. Patients with a coinfection had a risk of death of 5.92 (95% CI, 3.21-10.91) times greater than among those with neither influenza nor SARS-CoV-2 suggesting possible synergistic effects in coinfected individuals. The odds of ventilator use or death and ICU admission or death was also greatest among coinfected patients.

MedRxiv