First episodes of norovirus and sapovirus gastroenteritis protect against subsequent episodes in a Nicaraguan birth cohort

• Type of Material: Article
• Authors: Nadja A. Vielot, University of North Carolina, Chapel Hill; Yaoska Reyes, University of Nicaragua; Bryan Blette, University of North Carolina, Chapel Hill; Fredman González, University of Nicaragua; Christian Toval-Ruiz, University of Nicaragua; Lester Gutiérrez, University of Nicaragua; Samuel Vílchez, University of Nicaragua; Marta Diez-Valcarce, Emory University; Jan Vinjé, Centers for Disease Control and Prevention; Sylvia Becker-Dreps, University of North Carolina, Chapell Hill; Filemón Bucardo, University of Nicaragua
• Language: English
• Date: 2022-06-10
• Publisher: Wolters Kluwer Health, Inc.
• Publication Version: Author Accepted Manuscript (After Peer Review)
• Copyright Statement: © 2022 Wolters Kluwer Health, Inc. All rights reserved.
• Final Published Version (URL): https://doi.org/10.1097%2FEDE.0000000000001500
• Title of Journal or Parent Work: Epidemiology
• Volume: 33
• Issue: 5
• Start Page: 650
• End Page: 653
• Grant/Funding Information: This work was supported by the National Institute of Allergy and Infectious Diseases at the National Institutes of Health [R01AI127845 and K24AI141744] and the Fogarty International Center [D43TW010923 to L.G., F.G., and Y.R.].
• Keywords: Nicaragua; diarrhea; norovirus; children; gastroenteritis; sapovirus
• Research Categories: Health Sciences, Public Health; Health Sciences, Epidemiology

Abstract

Background: Norovirus and sapovirus cause a large burden of acute gastroenteritis (AGE) in young children. We assessed protection conferred by norovirus and sapovirus AGE episodes against future episodes. Methods: Between June 2017-July 2018 we recruited 444 newborns in León, Nicaragua. Weekly household surveys identified AGE episodes over 36 months, and AGE stools were tested by reverse transcriptase-quantitative polymerase chain reaction (RT-qPCR) for norovirus GI/GII and sapovirus. We used recurrent-event Cox models and negative control methods to estimate protection conferred by first episodes, controlling for observed and unobserved risk factors, respectively. Results: Sapovirus episodes conferred a 69% reduced hazard of subsequent episodes using the negative control method. Norovirus GI (HR: 0.67, 95% CI: 0.31, 1.3) and GII (HR: 0.20, 95% CI: 0.04, 0.44) episodes also appeared highly protective. Protection against norovirus GII was enhanced following two episodes. Conclusions: Evidence of natural immunity in early childhood provides optimism for the future success of pediatric norovirus and sapovirus vaccines.