A deterministic model approach of leptospirosis outbreaks in relation to climatic variables

GÓMEZ, ANDREA; LÓPEZ, MARÍA SOLEDAD; MÜLLER, GABRIELA; LÓPEZ, LEONARDO; WALTER SIONE; GIOVANINI, LEONARDO

Congreso; XIV Congreso de Meteorología; 2022

Leptospirosis is a zoonosis found worldwide and it is a major public health issue in many rural andurban surroundings in temperate and tropical climates. This vector disease is present especially in many countries of Latin America and South-East Asia. The reported yearly incidence usually ranges from 0.1 to 1 per 100,000 inhabitants in temperate climates and is higher than 10 per 100,000 inhabitants in tropical regions (Haake et al., 2015). The animal reservoir includes mostly rodents, they excrete leptospires in their urine and thus contaminate hydric environment, transmitting the disease to other animals or to humans (McBride et al., 2005).Outbreaks of leptospirosis in the northeast of Argentina occurred in months with moderate temperatures (late summer, early autumn) mainly coincident with El Niño event periods, characterized by flooding events caused by rivers levels increases or by abundant precipitation (López et al., 2016; 2019). This region accounts for the highest annual number of cases and deaths due to leptospirosis, being a top priority health issue at a regional level (Moral et al., 2014; López et al., 2019). The most affected cities were those with the largest population within each province.Susceptible-Infectious-Recovered Epidemiological Model (SIR) has been used to describe thetransmission dynamics of many infectious diseases, included leptospirosis. In this work we proposed a SIR model for leptospirosis outbreaks but incorporating hydroclimatic variables that influence the disease transmission in the northeast of Argentina, fitting the model to the actual data reported in outbreak events, in the three most populated cities in the area, Santa Fe, Rosario and Paraná, which have latitudinal and topographic differences. Each of these cities has experienced at east one outbreak since 2009.