Impact of obesity on host defences: Implications for SARS-CoV-2 infection

The role of obesity in the pathophysiology of respiratory virus infections has become particularly apparent during the current severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic, where obese patients are twice as likely to suffer from severe coronavirus disease 2019 (COVID-19) than healthy weight individuals Obesity results in disruption of systemic lipid metabolism promoting a state of chronic low-grade inflammation However, it remains unclear how these underlying metabolic and cellular processes promote severe SARS-CoV-2 infection Emerging SARS-CoV-2 data and studies of influenza A virus (IAV) show that viruses can further subvert the host’s altered lipid metabolism and exploit obesity-induced alterations in immune cell metabolism and function to promote chronic inflammation and viral propagation In this review, we outline the systemic metabolic and immune alterations underlying obesity and discuss how these baseline alterations impact the immune response and disease pathophysiology A better understanding of the immuno-metabolic landscape of obese patients may aid better therapies and future vaccine design