Brucella abortus detected in cheese from the Amazon region: differentiation of a vaccine strain (B19) from the field strain in the states of Pará, Amapá and Rondônia, Brazil

Abstract

RESUMO.-[Brucella abortus em queijos na região amazônica: diferenciação em cepa vacinal (B19) ou de infecção a campo nos estados do Pará, Amapá e Rondô-nia.] A brucelose é uma enfermidade infecto-contagiosa que causa grandes perdas econômicas à cadeia produtiva da carne e do leite, como consequência dos distúrbios reprodutivos nos animais, além de ser uma antropozoonose crônica. O objetivo deste estudo foi detectar DNA de Brucella spp. e fazer a distinção da cepa vacinal (B19) da cepa de infecção de campo. Foram adquiridas 66 amostras de diferentes queijos produzidos e comercializados em três Brucellosis is an infectious-contagious disease responsible for significant economic losses to the meat and milk supply chain, because it causes reproductive disorders in animals and is a chronic anthropozoonosis. This study was designed to detect the DNA of Brucella spp. in cheese and to differentiate between a vaccine strain (B19) and the field strain. Sixty-six samples of different cheeses which are produced and marketed in three states of the Brazilian Amazon region (Amapá [5 samples], Pará [55 samples] and Rondônia [6 samples]) were evaluated. Thirty-nine of these samples were from cheeses made from cow's milk, and 27 were from cheeses made from buffalo milk. Four of the 66 samples were from cheeses produced in milk processing plants regulated by the Federal Inspection Service (Serviço de Inspeção Federal); nine of the samples were from cheeses produced in processing plants regulated by the State Inspection Service (Serviço de Inspeção Estadual); five of the samples were from artisanal cheeses; and the remaining 48 samples were from informally produced cheese. DNA was obtained from the samples following a DNA extraction protocol, and PCR was conducted using primers B4 and B5 to detect Brucella spp. Primers eri1 and eri2 were used to differentiate the field strain from the B19 vaccine strain. The results showed that 21.21% (14/66) of the samples were positive for Brucella spp., of which 21.43% (3/14) were positive for the B. abortus field strain, and 7.14% (1/14) were identified as harboring vaccine strain B19. These results demonstrate that it is possible to identify Brucella spp. in cheese from the Amazon region using the PCR technique and to differentiate the B. abortus field strain from the B19 vaccine strain.INDEX TERMS: Brucella abortus, cheese, cattle, vaccine (B19), PCR.

The contamination rate of Brucella spp. in unpasteurized dairy products used in urban and rural areas of Hamadan County, west of Iran

“…Recently in Qatar, an outbreak of B. melitensis and B. abortus infections has been accompanying with camel milk drinking. The eating of unpasteurized raw milk and cheese has also been reported as an important source of human brucellosis in other Middle Eastern areas such as Saudi Arabia[21].Khalili et al in Kerman city-Iran reported that the rate of brucella contamination in the delivery tank to one of the dairy factories by polymerase chain reaction (PCR) method was 3.8%, which is more than our findings[22]. Movasagh et al taken 50 random samples of cow's milk and by…”

Análise Sanitária E Físico-Química E Adequação Bacteriológica Do Queijo Minas Artesanal Produzido Em Duas Propriedades

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Research Article Bovine brucellosis vaccine strain S19 detected in calves before vaccination

“…Some studies have demonstrated persistence and excretion of the S19 vaccine strain. This strain has been found in cheese (Miyashiro et al, 2007;Silva et al, 2016;Hérnandez-Carbajan et al, 2018), semen (Júnior et al, 2017;Lourencetti et al, 2018;Junqueira-Junior et al, 2018), urine, and milk of cows up to nine years of age (Pacheco et al, 2012).…”