(C-059) PRESIENTE: A Community-Based Prospective Cohort Study of Respiratory and Gastrointestinal Illness in Peru

Background: Acute respiratory infections (ARI) and acute gastroenteritis (AGE) contribute significantly to global morbidity and mortality. Incidence estimated using medically attended disease may severely underestimate their true burden, especially in low- and middle-income countries (LMIC) where access to healthcare is limited. Community-based, household surveillance studies in LMIC are crucial to accurately estimating the burden of ARI and AGE in settings such as Latin America where current data are limited, and household transmission may contribute to significant illness.

Objectives: To describe the study design and preliminary findings for a prospective, community-based cohort study initiated in Lima, Peru. This study will describe the incidence rate of specific ARI and AGE infections (including the role of household transmission) and the frequency of symptoms by pathogen in the study population.

Methods: Approximately 260 households will be recruited through stratified cluster-randomized sampling for a dynamic cohort of households. At enrollment and regular intervals, participants complete a sociodemographic, health, and household composition questionnaire. Over 18 months, participants self-administer daily electronic symptom questionnaires, with alternate day face-to-face confirmation by study staff and additional reporting on quality of life measures during each incident ARI/AGE event experienced. Anterior nasal swabs and stool samples are also collected for ARI and AGE events, respectively, and tested using multiplex real-time PCR to identify etiologic agents of illness. Finally, community wastewater is periodically collected for metagenomic analysis.

Results: Recruitment began in January 2025, targeting enrollment of 1,056 household members of all ages. As of February 5, 2025, 289 participants have enrolled from 105 households, achieving 27% of the target cohort size. Final enrollment and detailed results will be reported upon completion of data collection including demographic characteristics and pathogen detection.

Conclusions: This study will provide critical contemporary data on disease burden and impact, estimating incidence rates of infection among individuals and within households in Latin America, which can help inform intervention efforts, including vaccine development. This surveillance network offers a platform for further research into disease etiology and the evaluation of public health measures to mitigate disease.