Herd-level prevalence and associated risk factors for Mycobacterium avium subsp. paratuberculosis in cattle in the State of Paraíba, Northeastern Brazil.

A cross-sectional study based on a planned sampling was carried out to determine herd-level and animal-level prevalences, and to identify risk factors associated with herd-level prevalence for bovine paratuberculosis in the State of Paraíba, Northeastern Brazil. The state was divided into three sampling groups: sampling stratum 1 (mesoregion of Sertão), sampling stratum 2 (mesoregion of Borborema), and sampling stratum 3 (mesoregions of Zona da Mata and Agreste). For each sampling stratum, herd-level and animal-level prevalences were estimated by a two-stage sampling survey. In the first stage, a pre-established number of herds (primary sampling units) were randomly selected; in the second stage, a pre-established number of cows aged ≥24 months were randomly selected (secondary sampling units). Ten animals were sampled in herds with up to 99 cows aged over 24 months; 15 animals were sampled in herds with 100 or more cows aged over 24 months; and all animals were sampled in those with up to 10 cows aged over 24 months. In total, 2504 animals were sampled from 480 herds. Enzyme-linked immunosorbant assay (ELISA) test kits were used for Mycobacterium avium subsp. paratuberculosis (MAP) antibody detection. A herd was deemed positive for the presence of MAP if it included at least one positive animal in herds of up to 24 females, and two positive animals in herds with more than 24 females. The herd-level prevalence in the State of Paraíba was 34.5% (95% CI=30.2-39.1%), 26.6% (95% CI=20.2-34.2%) in the region of Borborema, 30.5% (95% CI=23.9-38.0%) in Agreste/Mata, and 41.4% (95% CI=34.0-49.1%) in Sertão. The animal-level prevalence was 10.7% (95% CI=7.3-15.4%) in the State of Paraíba, 7.9% (95% CI=5.2-11.7%) in the region of Borborema, 9.4% (95% CI=7.3-12.1%) in Sertão, and 13.9% (95% CI=6.2--28.3%) in Agreste/Mata. The frequency of seropositive animals per herd ranged from 6.7% to 100% (median of 20%). The risk factors identified were as follows: Sertão region (OR=1.9), more than 12 adult animals in the herd (OR=1.9), and not using maternity pens (OR=1.7). Our findings suggest that MAP herd-level seroprevalence in the State of Paraíba, Northeastern Brazil, is high, and support the idea that the use of maternity pens will be important for preventing transmission of MAP in the herds.

Leptospirose bovina no Estado da Paraíba: prevalência e fatores de risco associados à ocorrência de propriedades positivas / Bovine leptospirosis in Paraíba State: prevalence and risk factors associated with the occurrence of positive herds

Foram determinadas as prevalências de propriedades positivas e de animais positivos e identificados fatores de risco associados à leptospirose em vacas no Estado da Paraíba, Nordeste do Brasil. Foram aleatoriamente selecionadas 2.317vacas com idade ≥ 24 meses, procedentes de 450propriedades. Para o diagnóstico sorológico da infecção por Leptospira spp. foi empregado o teste de soroaglutinação microscópica (SAM), utilizando-se 24 sorovares como antígenos. Uma propriedade foi considerada positiva quando apresentou pelo menos um animal soropositivo. Das 450 propriedades investigadas 398 (89,7 por cento; IC 95 por cento = 86,6-92,2 por cento) apresentaram pelo menos um animal reagente na SAM para qualquer sorovar, e 1.349 (61,1 por cento; IC por cento = 56,6-65,4 por cento) animais foram soropositivos. O sorovar Hardjo foi o mais prevalente nas propriedades e nos animais, com frequências de 58,17 por cento e 54,69 por cento, respectivamente. Propriedade ser localizada no Sertão (odds ratio = 3,20; p = 0,003), presença de animais silvestres (odds ratio =2,89; p=0,005), não resfriar o leite (odds ratio =3,83; p=0,034) e presença de pastos alagados (odds ratio =2,36; p<0,001) foram identificados como fatores de riscos associados à prevalência de propriedades positivas. Conclui-se que a leptospirose encontra-se amplamente difundida em bovinos do Estado da Paraíba, o que reforça a necessidade de intensificação de medidas de prevenção e controle, como a vacinação dos rebanhos. De acordo com os resultados da análise de fatores de risco, sugere-se que o controle sanitário antes da introdução de animais, drenagem de áreas alagadas e melhora nas condições de manejo são importantes medidas para a prevenção da infecção.

Herd-level and animal-level prevalences were determined and risk factors associated with leptospirosis were identified in cows in the State of Paraíba, Northeastern Brazil. A total of 2,317 cows with ≥ 24 months of age from 450 herds were randomly sampled. For the serological diagnosis of Leptospira spp. infection, the microscopic agglutination test (MAT) was carried out using 24 serovars as antigens. A herd was considered positive when presented at least one seropositive animal. Of the 450 investigated herds, 398 (89.7 percent; 95 percent CI = 86.6-92.2 percent) presented at least one reactant animal at MAT to any serovar, and 1,349 (61.1 percent; 95 percent CI = 56.6-65.4 percent) animals were seropositive. Serovar Hardjo was the most prevalent in herds and animals, with frequencies of 58.17 percent and 54.69 percent respectively. Location of the herd in the Sertão (odds ratio = 3.20; p=0.003), presence of wildlife (odds ratio =2.89; p=0.005), not cooling milk (odds ratio =3.83; p=0.034) and presence of flooded pastures (odds ratio =2.36; p<0.001) were identified as risk factors for herd-level prevalence. It is concluded that leptospirosis is widely spread in cattle in State of Paraíba, which reinforces the need for increased prevention and control measures, such as vaccination of herds. According to the results of risk factors analysis it is suggested that the sanitary control before the introduction of animals, drainage of wetlands and improvement in management conditions are important measures to preventing the infection.

Prevalência de leptospirose em caprinos leiteiros do semiárido paraibano / Prevalence of leptospirosis in dairy goats in the semiarid region of Paraíba state

Este trabalho teve como objetivos determinar a prevalência de propriedades de caprinos leiteiros positivas e de animais soropositivos para leptospirose no semiárido paraibano. A amostragem foi delineada para a determinação da prevalência de propriedades positivas (focos) e de animais soropositivos para a infecção por Leptospira spp. No total, foram colhidas amostras de sangue de 975 animais procedentes de 110 propriedades leiteiras localizadas no Munícipio de Monteiro, microrregião do Cariri Ocidental, Estado da Paraíba. Para o diagnóstico da infecção por Leptospira spp., foi utilizado o teste de soroaglutinação microscópica (SAM), utilizando como antígenos 24 sorovares. Uma propriedade foi considerada foco quando apresentou pelo menos um animal soropositivo. As prevalências de propriedades positivas e de animais soropositivos foram de 43,6% (IC 95% = 34,2-53,4%) e de 8,7% (IC 95% = 5,7-12,9%), respectivamente. Nos animais, os sorovares mais frequentes foram Autumnalis (1,74%; IC 95% = 0,97-3,09%), Sentot (1,71%; IC 95% = 0,82-3,52%) e Whitcomb (1,39%; IC 95% = 0,65-2,93%), e nas propriedades, os sorovares Autumnalis (10,9%; IC 95% = 5,8-18,3%), Whitcomb (8,2%; IC 95% = 3,8-15,0%) e Sentot e Patoc (7,3%; IC 95% = 3,2-13,8%) foram os mais frequentes. Sugere-se que a infecção está distribuída em caprinos da região, e que há necessidade de implantação de medidas de controle e prevenção, com o intuito de reduzir a ocorrência da infecção e, consequentemente, diminuir perdas econômicas ocasionadas e bloquear a possível transmissão do agente aos seres humanos.

This study aimed to determine the prevalence of positive dairy goat herds and seropositive animals for leptospirosis in the semiarid region of Paraíba state, Brazil. Sampling was designed to determine the prevalence of positive herds (foci) and seropositive animals for leptospirosis. A total of 975 serum samples were collected from goats of 110 dairy herds in the Monteiro municipality, Western Cariri microregion of Paraiba. For the serological diagnosis of leptospirosis the microscopic agglutination test (MAT) was carried out using 24 Leptospira spp. serovars as antigens. A herd was considered positive when existed at least one seropositive animal. The prevalence of positive herds and seropositive animals were 43.6% (95% CI = 34.2-53.4%) and 8.7% (95% CI = 58.7-12.9%) respectively. The most frequent serovars in goats were Autumnalis (1.74%; 95% CI = 0.97-3.09%), Sentot (1.71%; 95% CI = 0.82-3.52%) and Whitcomb (1.39%; 95% CI = 0.65-2.93%), and by herd, serovars Autumnalis (10.9%; 95% CI = 5.8-18.3%), Whitcomb (8.2%; 95% CI = 3.8-15.0%) and Sentot and Patoc (7.3%; 95% CI = 3.2-13.8%) were the most frequent. It is suggested that leptospirosis is spread in goats in the region, and that there is need to implement control and preventive measures in order to reduce infection and economic losses, and to avoid possible transmission of infection to humans.