Pediatric Coronavirus Infection and Immunity: Common Cold Coronaviruses and SARS-CoV-2

The epidemiology of human coronaviruses (HCoV) is not well understood, particularly among children. The emergence of SARS-CoV-2 and the resulting, ongoing global pandemic highlight our limited understanding. Better understanding of both common cold coronavirus (ccCoV) and SARS-CoV-2 epidemiology among children will provide insight into how SARS-CoV-2 will transition to endemicity. To examine fundamental questions about HCoVs we used data from the Nicaraguan Pediatric Influenza Cohort Study (2011-2016, 2020-2021) and the Household Influenza Cohort Study (2020-2022). First, we characterized the burden and seasonality of ccCoVs in children in Chapter 2. In Chapter 3 we compared symptoms and severity of ccCoV infections and SARS-CoV-2 among children. We next evaluated the association of SARS-CoV-2 infection-induced immunity with infectivity and protection against infection. In Chapter 2 we observed that ccCoVs spread annually with the greatest burden among those aged 0-1. We found that prior infection was associated with slight protection against lower respiratory infection (LRI) among the youngest children. In Chapter 3 we characterized the symptom presentation of ccCoVs and SARS-CoV-2 infections and found that they were similar in symptom presentation. Interestingly, in children SARS-CoV-2 infections were as severe or less severe than ccCoV infections. In Chapter 4, we showed that infection-induced immunity was associated with protection against infection and decreased infectivity among adults and adolescents; however, while less infectious than adults, infection-induced immunity was not associated with decreased infectivity among children. By increasing our understanding of pediatric HCoV infection and immunity we can better prepare for SARS-CoV-2’s transition to endemicity where children will increasing represent the greatest proportion of primary SARS-CoV-2 cases.PhDEpidemiological ScienceUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/176640/1/frutosa_1.pd