Canine visceral leishmaniasis in Araçatuba, state of São Paulo, Brazil, and its relationship with characteristics of dogs and their owners: a cross-sectional and spatial analysis using a geostatistical approach

Abstract

BackgroundThe incidence of visceral leishmaniasis (VL), one of the most important neglected diseases worldwide, is increasing in Brazil. The objectives of this study were to determine the canine VL (CanL) seroprevalence in an urban area of Araçatuba municipality and to evaluate its relationship with the characteristics of dogs and their owners.ResultsThe CanL seroprevalence in the study area was 0.081 (95% credible interval [CI]: 0.068–0.096). The following covariates/categories were positively associated with the occurrence of a seropositive dog: more than 10 dogs that had lived in the house (odds ratio [OR] = 2.36; 95% CI: 1.03–5.43) (baseline: 0–10 dogs); house with dogs that previously died of VL (OR = 4.85; 95% CI: 2.65–8.86) or died of causes other than old age (OR = 2.26; 95% CI: 1.12–4.46) (baseline: natural or no deaths); dogs that spent the day in a sheltered backyard (OR = 2.14; 95% CI: 1.05–4.40); dogs that spent the day in an unsheltered backyard or the street (OR = 2.67; 95% CI: 1.28–5.57) (baseline: inside home). Spatial dependence among observations occurred within about 45.7 m.ConclusionsThe number of dogs that had lived in the house, previous deaths by VL or other cause, and the place the dog stayed during the day were associated with the occurrence of a VL seropositive dog. The short-distance spatial dependence could be related to the vector characteristics, producing a local neighbourhood VL transmission pattern. The geostatistical approach in a Bayesian context using integrated nested Laplace approximation (INLA) allowed to identify the covariates associated with VL, including its spatially dependent transmission pattern.Electronic supplementary materialThe online version of this article (10.1186/s12917-018-1550-9) contains supplementary material, which is available to authorized users.

Molecular and Seroepidemiological Survey of Visceral Leishmaniasis in Owned Dogs (Canis familiaris) in New Foci of Rural Areas of Alborz Province, Central Part of Iran: A Cross-Sectional Study in 2017

“…However, some studies have reported the rate of infection in older dogs due to the possibility of more contact with the sand flies (4, 22). There was no statistically significant difference between sex and leishmaniasis in this study, which was consistent with studies in 1992 in Portugal, 1996 in Greece, and 2018 in Brazil (21,23,24). In terms of clinical symptoms in dogs studied in this study, only 1 dog (11.1%) was symptomatic, indicating no significant relationship between positive cases and symptomatic dogs, which was consistent with study conducted in Meshkin-Shahr (13%), but not with a study in Croatia, in which 54% of seropositive dogs from 306 dogs studied with DAT test had clinical symptoms (25, 26).…”

“…In the present study, according to the statistical findings, there was no significant relationship between the age and infection rate of CVL. This was consistent with the results of a study in Brazil, which found no relationship between age and infection rates (21). However, some studies have reported the rate of infection in older dogs due to the possibility of more contact with the sand flies (4, 22).…”

Twice upon a time: The progression of canine visceral leishmaniasis in an Argentinean city

“…In other studies, dogs staying in the backyard were associated with L . infantum infection, as well as the number of dogs living in the same house [42,43]. In this study, the age of the dogs and the habit of sleeping outside the houses showed a significant association (F = 19.625, p<0.001); 6.44% of all sampled dogs slept indoor but this proportion rose to 21.43% when only puppies were considered.…”

Controle da leishmaniose visceral canina por eutanásia: estimativa de efeito baseado em inquérito e modelagem matemática

“…Essa atividade foi realizada conjuntamente com os agentes de endemias dos Centros de Controle de Zoonoses (CCZ) desses dois municípios. Os inquéritos sorológicos, descritos em detalhes em Costa et al 31 , consistiram na identificação e coleta de amostra de sangue dos cães para teste da LVC (TR-DPP-Bio-Manguinhos e ELISA), usando-se o protocolo da rotina do programa de controle. As áreas selecionadas foram definidas com base em estudos anteriores que identificaram aglomerados de alto risco da infecção humana na área urbana dos municípios 4,16 .…”

“…Outra limitação dos modelos é o pressuposto de que todos os cães estão expostos de forma homogênea ao risco de contato com o vetor. Porém, como observado por Costa et al 31 , o risco varia espacialmente, dependendo das características dos cães, de seus tutores e dos domicílios. Esses autores verificaram a existência de um padrão local da transmissão da infecção no entorno dos domicílios, relacionado com as características do vetor, e observaram uma associação positiva entre a infecção e o local onde os cães são mantidos ao longo do dia.…”