Abstract Title
Epidemiology of norovirus infections and acute gastro-enteritis in adults 65 yrs and older in peri-urban Lima, Peru.
Presenter
Claudio F Lanata, Instituto de Investigación Nutricional
Co-Author(s)
Claudio F. Lanata (1,2), Ana I. Gil (1), Rubelio Cornejo (1), Lucie Ecker (1), Alejandra Llican (1), Mishel Sandoval (1), Stefano Rios (1).
1 Instituto de Investigación Nutricional, Lima, Peru
2 Department of Pediatrics, School of Medicine, Vanderbilt University, Nashville TN, USA.
Abstract Category
Epidemology
Abstract
Background: As worldwide, Peruvian population is aging. Acute gastro-enteritis (AGE) in general, and norovirus in particular have important impact on morbidity and mortality in older adults, as reported in high income countries. No studies have been done in lower- and middle-income countries. We report preliminary findings of an active surveillance prospective study in older adults in peri-urban Lima, Peru.
Methods: 1000 adults 65-103 yrs were enrolled after a house-to-house census of the study area during feb-mar 2025. Surveillance for AGE is being conducted over a 12-month period through weekly home visits by trained field workers. Stool samples are collected for norovirus detection by RT-PCR during AGE episodes and monthly while asymptomatic. Clinical characteristics and health service utilization are recorded.
Preliminary results: By the end of April 2025, 398 AGE episodes have been detected, with a rate of 2.3 episodes per adult-yr. From 352 episodes tested, 11 (3.1%) were norovirus-positive, 7 GII (2%) and 4 GI (1%). We will do a nested case-control study, to determine the attributable fraction of norovirus AGE, matching them with stool samples from healthy participants by gender and age group. We will compare clinical characteristics of norovirus-positive and norovirus-negative AGE and learn how to classify moderate/severe norovirus AGE episodes in this population.
Conclusions: Preliminary results suggest that AGE and norovirus incidence in older adults is much higher than rates reported in USA. As the population ages, this burden is expected to rise, highlighting the need to prioritize norovirus vaccine testing and use in this population.
Methods: 1000 adults 65-103 yrs were enrolled after a house-to-house census of the study area during feb-mar 2025. Surveillance for AGE is being conducted over a 12-month period through weekly home visits by trained field workers. Stool samples are collected for norovirus detection by RT-PCR during AGE episodes and monthly while asymptomatic. Clinical characteristics and health service utilization are recorded.
Preliminary results: By the end of April 2025, 398 AGE episodes have been detected, with a rate of 2.3 episodes per adult-yr. From 352 episodes tested, 11 (3.1%) were norovirus-positive, 7 GII (2%) and 4 GI (1%). We will do a nested case-control study, to determine the attributable fraction of norovirus AGE, matching them with stool samples from healthy participants by gender and age group. We will compare clinical characteristics of norovirus-positive and norovirus-negative AGE and learn how to classify moderate/severe norovirus AGE episodes in this population.
Conclusions: Preliminary results suggest that AGE and norovirus incidence in older adults is much higher than rates reported in USA. As the population ages, this burden is expected to rise, highlighting the need to prioritize norovirus vaccine testing and use in this population.