RESUMO
Prevalence of serum antibodies for the bacterium Brucella sp. in a tropical human population. Brucellosis is a systemic bacterial disease that can last years if not treated properly. The laboratory diagnosis is made by serological tests or isolation of the agent. We studied the prevalence of antibodies against Brucella sp. in inhabitants of rural communities of Cartago, Costa Rica, who are dedicated mainly to dairy cattle activities. We analyzed 714 representative samples with the Rose Bengal plate agglutination test (RBT) and the standard agglutination test in microplate (SAT). The overall prevalence was 0.87 %. No seroconversion was demonstrated for seropositive individuals. Even though 71 % of the population mentioned consuming non-pasteurized milk, no statistically significant association was found (1.09 %, IC 0.30-2.77) between milk consumption and the presence of antibodies suggestive of infection by Brucella sp. As a brucellosis high-risk population, the absence of symptoms in the population agrees with the observed titers of antibodies, suggesting a low previous exposure to the agent. Rev. Biol. Trop. 55 (2): 385-391. Epub 2007 June, 29.
La brucelosis es una enfermedad bacteriana generalizada con tendencia a la cronicidad si no se trata adecuadamente. El diagnóstico de laboratorio se realiza por el aislamiento e identificación del agente o en la mayoría de los casos mediante pruebas serológicas. En este estudio se informa la prevalencia de anticuerpos séricos contra Brucella sp. en habitantes de comunidades rurales de Cartago dedicadas principalmente a la ganadería de leche. Se analizó un total de 714 muestras representativas de la población mediante la técnica de aglutinación Rosa de Bengala en lámina (RBT) y la prueba de aglutinación en microplaca (SAT). Se encontró una prevalencia de 0.87 %, y en ninguna persona seropositiva se demostró seroconversión. Aún, cuando el 71 % de la población refirió consumir leche no pasteurizada, no se encontró asociación estadísticamente significativa (1.09 %, IC 0.30-2.77) entre el consumo de leche no pasteurizada y la presencia de anticuerpos sugestivos de infección por Brucella sp. A pesar de ser una zona de alta prevalencia de brucelosis bovina por Brucella abortus, la ausencia de síntomas en la población y los bajos títulos de anticuerpos observados sugieren una escasa exposición previa al agente.
Assuntos
Adolescente , Adulto , Idoso , Animais , Bovinos , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Anticorpos Antibacterianos/sangue , Brucella/imunologia , Brucelose/epidemiologia , Testes de Aglutinação , Brucelose/diagnóstico , Costa Rica/epidemiologia , Métodos Epidemiológicos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , População RuralRESUMO
Prevalence of serum antibodies for the bacterium Brucella sp. in a tropical human population. Brucellosis is a systemic bacterial disease that can last years if not treated properly. The laboratory diagnosis is made by serological tests or isolation of the agent. We studied the prevalence of antibodies against Brucella sp. in inhabitants of rural communities of Cartago, Costa Rica, who are dedicated mainly to dairy cattle activities. We analyzed 714 representative samples with the Rose Bengal plate agglutination test (RBT) and the standard agglutination test in microplate (SAT). The overall prevalence was 0.87%. No seroconversion was demonstrated for seropositive individuals. Even though 71% of the population mentioned consuming non-pasteurized milk, no statistically significant association was found (1.09 %, IC 0.30-2.77) between milk consumption and the presence of antibodies suggestive of infection by Brucella sp. As a brucellosis high-risk population, the absence of symptoms in the population agrees with the observed titers of antibodies, suggesting a low previous exposure to the agent.