COVID-19 and mental health risks in children: A role for biomarkers of inflammation, stress and the gut-brain axis

Viral infections during childhood can increase susceptibilities to neurodevelopmental and psychiatric disorders. We are currently in the early years following a viral pandemic caused by the rapid evolution of highly transmissible, host-evading variants of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2). Here we place this virus and the disease it generates, Coronavirus Disease 2019 (COVID-19), in the context of inflammatory host phenotypes and psychosocial factors which exacerbate stress to the developing human nervous system. While exposures to pathogens and inflammation during neurodevelopment are well-studied risk factors in psychiatric research, the subtle effects on a child’s physiology of factors such as social isolation, food insecurity, and other social determinants of health are more difficult to identify and quantify. In this post-pandemic era, we have the unique opportunity to initiate in local community healthcare facilities, inclusive longitudinal studies to measure pandemic-mediated mental health outcomes in children of all races, ethnicities, genders, and other groups shaped by social, cultural, and as yet unidentified determinants. Toward this end, the identification of children in need of prompt psychiatric intervention may be accelerated by the use of biomarkers indicating COVID-19 infection status, inflammation, imbalances of the gut-brain axis, and acute and chronic stress. Especially promising are approaches combining these biomarkers with mental health screening tools such as the Child Behavior Checklist (CBCL) and the Epic Patient Healthcare Questionnaire 9 (PHQ9).