Abstract
Brucella was discovered as a pathogen of marine mammals in 1994.1,2 Like the classical Brucella spp., marine isolates also appear to cause serious disease in their animal hosts and humans.3,4,5 Marine brucellosis is thus a relevant disease that poses potential risks to human health and jeopardizes species conservation. Routes of transmission of marine Brucella spp. are poorly understood. We hypothesize that fish are naturally infected with Brucella and are a potential source of disease for marine mammals and humans.
The aim of this study was to investigate whether Brucella infection could be detected in a population of Atlantic herring (Clupea harengus) harvested from the coast of southern New England, an area in which Brucella spp. have previously been isolated from marine mammals.6 Sample size (n=60) was calculated based on that required to detect infection in the population given an assumed 5% prevalence rate and a 95% confidence interval. Samples of liver and spleen were collected from all fish and extracted DNA was subjected to polymerase chain reaction (PCR) analysis. A real-time multiplex PCR assay that targets the Brucella genus-specific gene bcsp31 was utilized in this study.7
All liver (n=60) and spleen (n=12) samples were found to be PCR negative. Therefore, we conclude that the prevalence of Brucella infection in the southern New England population of Atlantic herring is less than 5%. As experimental infection of marine fish with B. pinnipedialis has recently been demonstrated,8 further work should be conducted to investigate natural infection of marine fish with Brucella spp.
* Presenting author
+ Student presenter
Literature Cited
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