BACKGROUND: Previous studies suggest a relationship between precipitation and ocular toxoplasmosis (OT) reactivation and congenital toxoplasmosis infection. We aimed to investigate the relationship between precipitation and the frequency of new OT cases in Colombia from 2015 to 2019. METHODOLOGY: This retrospective cohort study analyzed data obtained from a claims-based database created by the Colombian Ministry of Health and national registries of precipitation of the Institute of Hydrology, Meteorology, and Environmental Studies. We estimated the daily number of OT cases, interpolating data from the average number of annual cases from 2015 to 2019. Then, we compared exposures (mean daily precipitation) in the case period in which the events (interpolated OT new cases) occurred by a quasi-Poisson regression, combined with a distributed lag non-linear model to estimate the non-linear and lag-response curve. PRINCIPAL FINDINGS: In the 5-year analysis, there were 1,741 new OT cases. Most of the cases occurred in 2019, followed by 2015 and 2018. New OT cases among departments were significantly different (Pylt; 0.01). The cumulative exposure-response curve was decreasing for most departments. Nevertheless, in Chocó, Bogotá, Cesar, Cauca, and Guajira, when a certain amount of precipitation accumulates, the relative risk (RR) increases, which was contrary to the pattern observed in the other regions. The response curves to the one-day lag showed that precipitation influences the RR; however, the trends vary by department. Finally, an increasing trend in the number of cases was directly proportional to precipitation in Guajira, Atlántico, Norte de Santander, Santander, Caquetá and Quindío (r = 0.84; Pylt; 0.05). CONCLUSIONS: Precipitation influenced the RR for new OT cases. However, varying trends among geographical regions (departments) lead us to hypothesize that other sociodemographic, behavioral, and environmental variables, such as wind and water contamination, could influence the RR.
FondoEstudios previos sugieren una relación entre la precipitación y la reactivación de la toxoplasmosis ocular (OT) y la infección por toxoplasmosis congénita. Nuestro objetivo fue investigar la relación entre la precipitación y la frecuencia de nuevos casos de TO en Colombia de 2015 a 2019.MetodologíaEste estudio de cohorte retrospectivo analizó datos obtenidos de una base de datos basada en reclamos creada por el Ministerio de Salud de Colombia y los registros nacionales de precipitación del Instituto de Hidrología, Meteorología y Estudios Ambientales. Estimamos el número diario de casos de OT, interpolando datos del número promedio de casos anuales de 2015 a 2019. Luego, comparamos las exposiciones (precipitación diaria promedio) en el período del caso en el que ocurrieron los eventos (casos nuevos de OT interpolados) por un regresión cuasi-Poisson, combinada con un modelo no lineal de retraso distribuido para estimar la curva de respuesta no lineal y de retraso.
