Internal medicine

Virus

Cytomegalovirus

Disease

Respiratory tract

Coronavirus disease 2019 (COVID-19)

Infectious disease (medical specialty)

Biology

Virology

Herpesviridae

Immunology

Respiratory tract infections

Coronavirus

Viral disease

Human cytomegalovirus

Respiratory system

Medicine

Immune system

The Journal of Infectious Diseases

Some risk factors for severe coronavirus disease 2019 (COVID-19) have been identified, including age, race, and obesity. However, 20%–50% of severe cases occur in the absence of these factors. Cytomegalovirus (CMV) is a herpesvirus that infects about 50% of all individuals worldwide and is among the most significant nongenetic determinants of immune system. We hypothesized that latent CMV infection might influence the severity of COVID-19. Our analyses demonstrate that CMV seropositivity is associated with more than twice the risk of hospitalization due to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Immune profiling of blood and CMV DNA quantitative polymerase chain reaction in a subset of patients for whom respiratory tract samples were available revealed altered T-cell activation profiles in absence of extensive CMV replication in the upper respiratory tract. These data suggest a potential role for CMV-driven immune perturbations in affecting the outcome of SARS-CoV-2 infection and may have implications for the discrepancies in COVID-19 severity between different human populations.

Cytomegalovirus Latent Infection is Associated with an Increased Risk of COVID-19-Related Hospitalization