Search

Bovines and equines are the domestic animals with the highest incidence of rabies in Brazil. This study evaluated the data input in testing request forms for rabies in herbivores accompanying samples sent to a certified laboratory of rabies diagnosis in the state of Rio Grande do Sul, Brazil. Information was obtained systematically from all forms sent to the laboratory in 2013 and 2014 using a collection instrument that listed variables about the kind of form used, municipality of origin, description of the suspected animal, clinical signs, sample collection, and conservation procedure. The 11 most relevant variables (municipality of origin, geographic coordinates, species, gender, breed, age, herd size, clinical signs, persistence of clinical signs, biological material, and sample conservation) were assessed for the quality of the data entered, and percentage data input was calculated per form. In total, 603 forms were sent to the laboratory. The most used form was the FORM SN, (82.0%, 497/603). “Excellent” and “good” data inputs were observed only for one variable describing the location of suspected rabies cases or outbreaks and animals (species, gender, biological material). Quality of data input of variables describing geographic coordinates, age, breed, herd size, clinical signs, persistence of signs, and sample conservation method varied between “average” and “poor”. The data input in testing request forms for herbivores are not dully supplied in suspected cases neurological syndromes, pointing to the need to increase awareness and improve training of field staff. RESUMO: Bovinos e equinos são os animais domésticos com maior incidência de raiva no Brasil. Este estudo avaliou formulários de solicitação de testes para raiva em herbívoros acompanhando amostras enviadas a um laboratório certificado de diagnóstico de raiva no estado do Rio Grande do Sul, Brasil. As informações foram obtidas sistematicamente de todos os formulários enviados ao laboratório em 2013 e 2014 utilizando um instrumento de coleta que selecionou variáveis sobre o tipo de formulário utilizado, município de origem, descrição do animal suspeito, sinais clínicos, coleta de amostra e procedimento de conservação. As 11 variáveis mais relevantes (município de origem, coordenadas geográficas, espécie, gênero, raça, idade, tamanho do rebanho, sinais clínicos, persistência de sinais clínicos, material biológico e conservação da amostra) foram avaliadas quanto à qualidade dos dados inseridos, e os dados percentuais foram calculados por formulário. No total, 603 formulários foram enviados para o laboratório. O formulário mais utilizado foi o FORM SN, (82,0%, 497/603). Dados classificados como “excelentes” e “bons” foram observados apenas para uma variável que descreve a localização de casos suspeitos de raiva ou surtos e animais (espécie, gênero, material biológico). A qualidade da entrada dos dados das variáveis que descrevem coordenadas geográficas, idade, raça, tamanho do rebanho, sinais clínicos, persistência de sinais e método de conservação da amostra variou entre “regular” e “ruim”. A qualidade dos dados dos formulários de solicitação de testes para herbívoros não foi devidamente fornecida em casos suspeitos de síndromes neurológicas, apontando para a necessidade de aumentar a conscientização e melhorar o treinamento do pessoal de campo.

Background: Rabies remains one of the most important zoonosis worldwide and in Brazil. In the Brazilian state of Rio Grande do Sul (RS) the disease is one of the main causes of death in bovine herds. The confirmation of suspected rabies cases upon clinical examination depends on specific laboratory diagnosis. The Instituto de Pesquisas Veterinárias Desidério Finamor (IPVDF) is the reference laboratory in RS to diagnose rabies. The objective of the present study was to present a spatial-temporal description of diagnostic procedures of rabies in cattle in the years 2011 to 2015 in RS.Materials, Methods & Results: The results of diagnosis procedures of rabies in cattle carried out in the Laboratory of Virology, IPVDF, between January 2011 and December 2015 were listed. Direct immunofluorescence (DIF) and biological assays for confirming rabies cases were used. Cattle population density per area of a municipality, as well as date, species involved, location of suspected case, and diagnosis were obtained from exams and from official rabies record, and input to a spreadsheet file. Spatial distribution maps of cattle rabies confirmed in laboratory and cattle population density per municipality were constructed using the software TerraView 4.2.2 (INPE). In the study period, 998 samples of brains of cattle presenting neurological symptoms compatible with rabies, of which 582 (58%) were confirmed in the laboratory. The frequency of positive cases on a yearly basis varied between 41 and 65%, with statistically lower number of positives in 2011 (P > 0.05). The annual incidence of rabies for a population of 10,000,000 bovines was 33, 88, 112, 108, and 79, respectively, for the years 2011 to 2015, in that order. A positive correlation was observed between the number of samples analyzed and the incidence of positive cases in the study period, and statistically significant difference in incidence between years (P > 0.05). Samples were from 175 municipalities, of which 114 (65%) had at least one confirmed rabies case and 61 did not have any. The five municipalities that sent most samples for analysis were Viamão (n = 66), Montenegro (n = 40), Camaquã (n = 39), Gravataí (n = 38), and São Lourenço do Sul (n = 37). The spatial distribution of rabies in cattle in a year did not follow a defined pattern, though most cases confirmed in the laboratory occurred in the greater Porto Alegre region and in southeast RS.Discussion: High incidence of rabies was observed in 2012 and 2013, and in the two following years the number of cases confirmed in laboratory remained high, compared with 2011. The high incidence of rabies cases confirmed in laboratory correlated with the number of samples analyzed. The fall in vaccine coverage during the study period may also have prompted the increase in suspected cases and in the number of samples examined in the laboratory. A large number of the municipalities presenting rabies cases in cattle was in the greater Porto Alegre region and in southeast RS, which are areas of high and intermediate risk for the disease, according to a previous epidemiological modeling study. The spatial distribution of positive cases was not associated with the cattle population density. The large number of rabies in cattle in RS underscores the importance of the disease and the high risk of exposure, both to humans and animals. The results presented herein may help define control and prevention actions against rabies in RS.