Identifying the role of household immunity in driving individual dengue virus infection risk

Dengue virus (DENV) infection risk is known to vary substantially, even across small communities, with infections in and around the home driving transmission. However, It remains unclear how the immune status of an individual or household dictate this risk in part due to transmission being dominated by subclinical infections. In this study, we used demographic, household characteristic, and serological data from a multigenerational cohort study of 2860 individuals from 470 households in Kamphaeng Phet, Thailand, to determine the incidence and risk factors for DENV infections. We used hemagglutination inhibition (HAI) antibody titers measured in sequential serum samples to identify subclinical infections through a gradient boosted regression model. This approach identified ∼10% more cases than commonly used methods with approximately 90% of all infections being subclinical. As expected, we found that having higher DENV antibody titers was protective against infection. Individuals were additionally protected if other household members had higher titers suggesting that there are indirect effects of household immunity on the individuals found within a household. Our study provides a framework for inferring subclinical infections and characterizing the epidemiology of DENV infection in households. ### Competing Interest Statement The authors have declared no competing interest. ### Funding Statement The NIH Grant P01 AI034533 and R35 GM138361 supported the work. ### Author Declarations I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained. Yes The details of the IRB/oversight body that provided approval or exemption for the research described are given below: This study was approved by Thailand Ministry of Public Health Ethical Research Committee, Siriraj Ethics Committee on Research Involving Human Subjects, Institutional Review Board for the Protection of Human Subjects State University of New York Upstate Medical University, and Walter Reed Army Institute of Research Institutional Review Board (protocol #2119). I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals. Yes I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance). Yes I have followed all appropriate research reporting guidelines and uploaded the relevant EQUATOR Network research reporting checklist(s) and other pertinent material as supplementary files, if applicable. Yes All data and code associated with the work can be found at https://github.com/marcohamins/role-of-HH-immunity.