Comparison of Clinical and Epidemiologic Characteristics of Young Febrile Infants with and without SARS-CoV-2 Infection

Leibowitz, Jill; Krief, William; Barone, Stephen; Williamson, Kristy A.; Goenka, Pratichi K.; Rai, Shipra; Moriarty, Shannon; Baodhankar, Prachi; Rubin, Lorry G.

OBJECTIVE: To determine features that distinguish febrile young infants with SARS-CoV-2 infection. STUDY DESIGN: Retrospective single-center study included febrile infants <57 days evaluated in the Emergency Department of Cohen Children’s Medical Center of Northwell Health, New Hyde Park, New York during March 1-April 30 of 2018, 2019, and 2020. Sociodemographic and clinical features were compared between those seen during the 2020 COVID-19 pandemic and previous years, as well as between SARS-CoV-2 infected infants and SARS-CoV-2 uninfected infants (SARS-CoV-2 negative or evaluated during 2018 and 2019). RESULTS: In all, 124 febrile infants <57 days of age were identified; 38 during the 2-month study period in 2018, 33 in 2019, and 53 in 2020. During 2020, fewer febrile infants had a serious bacterial infection (SBI) or a positive respiratory viral panel (RVP) than in prior years (6% versus 21%, P = .02; 15% versus 53%, p<.001, respectively). SARS-CoV-2 was the most frequent pathogen detected in 2020; of 30 infants tested, 20 tested positive. Infants with SARS-CoV-2 were more likely to identify as Hispanic (p=.004), have public insurance or were uninsured (p=.01), exhibited lethargy (p=.02), had feeding difficulties (p=.002), and had lower white blood cell (p=.001), neutrophil (p<.001), and lymphocyte counts (p=.005) than the 81 infants without SARS-CoV-2 infection. None of the infants with SARS-CoV-2 had concurrent SBI or detection of another virus. Overall, disease in infants with SARS-CoV-2 was mild. CONCLUSIONS: During the peak of the pandemic, SARS-CoV-2 was the predominant pathogen among febrile infants. Socioeconomic, historical, and laboratory features differed significantly between SARS-CoV-2 infected and uninfected infants. None of the 20 infants with SARS-CoV-2 infection had an identified co-viral or serious bacterial infection.