Environmental exposures are hidden modifiers of anti-viral immunity.

Significant advances have been made recent years elucidating antiviral immune mechanisms that protect the host from viral infection. Similarly, our understanding of how viruses bind, enter, and replicate within host cells has continued to grow. Yet, viruses continue to take a toll on human health. The influence of chemicals in the environment is among key factors that influence outcomes of viral infection. There is a growing appreciation of the effects that exogenous environmental chemical exposures have on the immune system and antiviral immunity. Epidemiological studies have linked a variety of chemical exposures to poorer health, increased incidence of infection, and worsened vaccine responses. However, the mechanisms that govern these associations are not well understood, limiting our ability to predict or mitigate the effects of environmental exposures on public health. This brief review focuses on recent advances in the field, highlighting novel in vitro and in vivo findings informed by past foundational studies. Furthermore, current information suggests avenues of investigation that have yet to be explored, but which will significantly impact on our understanding about how environmental exposures impact viral defenses, vaccine efficacy, and the spread of contemporary and emerging viral pathogens.