Geographic analysis on the occurrence of human and canine leptospirosis in the city of Maringá, state of Paraná, Brazil

Abstract

INTRODUCTION: Leptospirosis is a zoonotic disease, the primary hosts of which are wild, synanthropic, and household animals. Humans behave as terminal and accidental hosts. The prevalence of leptospirosis depends on carrier animals that disseminate the agent, on the environmental survival of this agent, and on the contact of susceptible individuals. Each serovar has one or more hosts with different adaptation levels. The focuses of leptospirosis are infected, sick, and asymptomatic animals, which are considered to be sources of environmental infection. This study aimed to determine the risk areas for leptospiral infection in stray dogs and patients diagnosed with leptospirosis from 2006 to 2008 in Maringá, State of Paraná, Brazil. METHODS: Three hundred and thirty-five stray dogs and 25 patients were studied. Serum from both animals and patients was examined by the microscopic serum agglutination test to study anti-leptospiral antibodies. To determine the risk areas and the spatial distribution of the disease, thematic maps were designed. RESULTS: Forty-one (12.2%) dogs positive for one or more leptospire serovars were observed, the most frequent serovars being Pyrogenes (43.9%), Canícola (21.9%), and Copennhageni (19.5%). Among the humans, 2 (8%) were positive for serovars Pyrogenes and Hardjo Prajitno and for Pyrogenes and Cynopteri. CONCLUSIONS: Spatial analysis showed that the risk for dogs and humans in the City of Maringá to become infected with leptospires exists in both the central and the peripheral areas, a fact that reinforces the relevance of this study and of continuous epidemiological and environmental surveillance actions to control the disease in animals and in humans.

Seroprevalence and seroincidence of Leptospira infection in dogs during a one-year period in an endemic urban area in Southern Brazil

“…The serogroups associated with human infection (6) (13) (14) also suggest that the role of dogs in human infection may be limited or non-existent (15) . Regardless, there is general consensus that canine disease acts as an indicator for METHODS human exposure risk (16) ; dogs are more frequently exposed to known risk factors of disease and thus may act as sentinels of environmental contamination (15) (17) . (17) , 30.5% in dogs treated in a Veterinary Teaching Hospital in Northern State (24) , and 32.2% (n = 598) in diagnostic serum samples taken from dogs in Curitiba (23) .…”

“…Regardless, there is general consensus that canine disease acts as an indicator for METHODS human exposure risk (16) ; dogs are more frequently exposed to known risk factors of disease and thus may act as sentinels of environmental contamination (15) (17) . (17) , 30.5% in dogs treated in a Veterinary Teaching Hospital in Northern State (24) , and 32.2% (n = 598) in diagnostic serum samples taken from dogs in Curitiba (23) . Only one study of incidence rates in dogs has been conducted, which reported an annual incidence of 28.9% in a slum community of Curitiba City (25) .…”

Incidence of canine leptospirosis in the metropolitan area of Curitiba, State of Parana, Southern Brazil

“…In particular, the seroprevalence values have been reported to range from 10.5% to 34.8% in the southern region of Brazil, between 6.6% and 17.9% in the southeast, between 10% and 30.9% in the midwest, at 27.3% in the north and between 20% and 85% in the northeast. The most prevalent serovars have been Canicola, Copenhageni and Pyrogenes [4][5][6][7][8] . Serology for leptospirosis lasts three months for any serovar.…”

A serological survey of agents causing leptospirosis and toxoplasmosis in Rattus rattus in the city of Umuarama, northwest Paraná, Brazil

“…The Copenhageni and Pyrogenes serovars detected in this study can reportedly infect humans (GONÇALVES, 2009;FONZAR;LANGONI, 2012). In Brazil, there were 1,827 deaths from leptospirosis between 2011 to 2016 according to the National Medical Service System (SINAM, c2016), and so epidemiological studies to investigate patterns of infection and establish the dominant causative serovars are crucial for disease prevention and public health education measures.…”

“…This serovar is now routinely included in serological assays for infection with Leptospira for several animal species, and recent studies have shown its prevalence in goats and sheep (HIGINO; AZEVEDO, 2014), dogs (FONZAR;LANGONI, 2012;MASCOLLI et al, 2016;SAMIR et al, 2015), and humans (FONZAR; LANGONI, 2012;SAMIR et al, 2015;BRASIL, 2010b).…”