Development of high-performance immunoassay for Brucella canis and seroprevalence survey in humans and dogs of Buenos Aires urban area

REY SERANTES D.A.; NOVAK A.; CORTINA, MARÍA E.; UGALDE, J. E.; CIOCCHINI A. E.; COMERCI D. J

Buenos Aires

Congreso; 18th International Congress on Infectious Diseases - XVIII Congreso SADI; 2018

ICID

BackgroundBrucellosis remains as one of the most common zoonotic diseases worldwide. The infection is caused by intracellular facultative Gram-negative bacteria of the genus Brucella. Based on the lipopolysaccharide (LPS) structure, Brucella may occur either as smooth (S) or rough (R) species. Brucella canis causes disease in dogs and is the only one rough Brucella species that can infect humans. The public health impact of this urban zoonosis is not clear due to the lack of high performance laboratory diagnostic tests. For this reason, early and accurate diagnosis of brucellosis from dog origin is central to control the disease.Methods & MaterialsWe developed and validated an improved enzyme and lateral flow immunoassays for the serodiagnosis of B. canis. To validate the assays, 284 dog sera obtained from naturally infected or healthy animals and 582 human sera from both infected patients or healthy donors were analyzed and the diagnostic specificity and sensitivity were determined. Finally, a blind serological survey was conducted including 1,040 serum samples obtained from urban dogs and 607 serum samples from human donors both from the Buenos Aires urban area.ResultsThe results showed a prevalence higher than 5% in the dog population and near to 5% in humans highlighting the need of implementing new high-performance serological test as an effective way to improve the control of this neglected urban zoonosis and reduce the risk of transmission to humans.ConclusionCanine brucellosis has been considered as an infection of low zoonotic potential. This misconception influenced the paucity of scientific advance on this subject, which is reflected in the scarce high precision diagnostic tests that exist today. In recent years, several reports of human brucellosis cases with confirmed isolation of B. canis raised a red flag on this neglected urban zoonosis.