Estudo epidemiológico-molecular da infecção por Mycobacterium avium subsp. paratuberculosis (Map) em ovinos e percepção dos médicos veterinários e produtores rurais sobre a paratuberculose no estado de Pernambuco, Brasil

Abstract

Paratuberculosis is caused by the bacterium Mycobacterium avium subsp. paratuberculosis (Map). The disease can cause chronic enteritis problems and affect ruminants, including sheep, worldwide, and is also responsible for several economic losses when the infection is present in the herd. The aim of this research was to systematically review and perform a meta-analysis of the general prevalence of Map infection in sheep, as well as an epidemiological-molecular study of infection in sheep farms and to analyze the perception of veterinarians and rural producers about the disease in the state of Pernambuco, Brazil. We analyzed 27 studies after selection in six databases, belonging to 18 countries and on five continents. After the random model meta-analysis, an overall prevalence of 8.79% (95% CI, 4.89–13.66) was verified. The prevalence values were separated by region, with high heterogeneity (I2 = 99%) and significant differences between regions (p = 0.0319). The Egger’s test was performed to analyze possible publication biases and significant bias was observed (p = 0.0244). For the epidemiological-molecular study, 276 blood samples and 261 fecal samples were collected from asymptomatic sheep from ten farms in the state of Pernambuco, Brazil. Subsequently, the blood samples were submitted to the serological test of Enzyme-Linked Immunosorbent Assay (ELISA; IDEXX Paratuberculosis Screening®). The fecal samples were processed for microbiological culture and molecular analysis by Polymerase Chain Reaction (PCR). Of the 276 serum samples analyzed, 0.72% (n = 2/276) were positive for anti-Map antibodies. At the microbiological examination, no colonies suggestive of Map were observed, as well as all samples were negative in PCR. An investigative questionnaire on paratuberculosis and biosecurity practices was applied to 84 veterinarians and 54 rural producers in the state of Pernambuco. Significant differences were observed between the groups of veterinarians (VE) and rural producers (RP) in different questions (p > 0.05). 97.62% (VE = 82/84) and 55.56% (RP = 30/54) answered yes to knowledge about paratuberculosis, while those who answered whether they had ever had cases of paratuberculosis were 26.19% (VE = 22/84) and 11.11% (RP = 6/54) (p = 0.0013). Regarding biosecurity practices, 1.19% (n = 1/84) of veterinarians and 44.44% (n = 24/54) of rural producers were unaware of the term, and a significant difference was observed between the biosecurity practices performed by VE and RP, such as the separation of sick animals in the herd (p < 0.0001). The results of the research suggest that there is exposure to Map in sheep herds in the state of Pernambuco, Brazil. Despite the low prevalence, the results are important from the epidemiological point of view of the disease. Thus, periodic monitoring of sheep herds is necessary because it is a chronic and asymptomatic disease that can cause serious damage to rural producers and is distributed in several regions of the world as observed through the general prevalence of the systematic review. Regarding the perception analysis, it can be concluded that in the group of veterinarians, there are quite gaps in knowledge regarding paratuberculosis and biosecurity practices and it was found that rural producers are unaware of the disease. Thus, the adoption of educational policies for rural producers is a way to improve the reach of this group to this information.