Serological and Molecular Study on Caprine Brucellosis in Puducherry (India) and its Public Health Significance

Abstract

Caprine brucellosis due to Brucella melitensis is an important zoonotic disease. The present study was carried out to address the lack of a comprehensive study on the status of caprine brucellosis in Puducherry, India using serological and molecular tests in goats and to assess the seroprevalence in human risk groups of the aforementioned region to ascertain the public health significance of the disease. Seroprevalence in 120 goats was found to be zero, 3.33% and 18.33% by Rose Bengal agglutination Test (RBT), Standard Tube Agglutination Test (STAT) and Immunoglobulin G Indirect Enzyme Linked Immune Sorbant Assay (IgG iELISA) respectively. Of the 120 goat genital swabs screened, while conventional polymerase chain reaction (PCR) detected genus specific 16S rRNA and Brucella melitensis specific omp2 genes in 17.50% and 5.00% of samples respectively, the OMP31TaqMan® real time PCR with a positive detection of 40.00% was both the most sensitive and specific for detection of Brucella melitensis. The study provides insight into the optimization of diagnostic tests following cluster wise sampling for brucellosis in goats. The strain of B. melitensis in Puducherry was found to be Biovar 3 based upon suggestive results of Restriction Fragment Length Polymorphism (RFLP) of omp2 gene product. Seroprevalence by IgG iELISA was 33.33 % in 30 samples from human subjects. Serological evidence of caprine brucellosis in goats and human subjects and molecular detection of B.melitensis in Puducherry, India warrants regular screening, surveillance and reporting of disease in goats and human risk groups.

Seroepidemiology and associated risk factors of brucellosis in small ruminants of district Khanewal, Pakistan

“…Some previous studies have reported an apparently lower prevalence of brucellosis in small ruminants of different parts of the world, such as 0.99% in the western borders of Pakistan [ 8 ], 6.6% in Kampala, Uganda [ 19 ], 5.59% in Tamil Nadu, India [ 20 ], and 5.8% in Kurdistan, Western Iran [ 21 ]. In contrast to current findings, some previous studies also reported a higher prevalence of brucellosis in small ruminants, such as 12.29% in district Kasur and Sheikhupura, Pakistan [ 15 ], 15.5% in goat and 8.6% in sheep populations of Baringo County, Kenya [ 22 ], 18.3% in Puducherry, India [ 10 ], 18.5% in Tarbiz, Iran [ 23 ], and 31.25% in goat and 22.5% in sheep populations of Matrouh governorate, Egypt [ 9 ]. The difference in values might be due to differences in diagnostic techniques, agroecological zones, geoclimatic conditions, husbandry practices, and traditions and culture [ 24 ].…”

“…A single infected male can sexually transmit the disease to several females [ 7 ]. A considerable variation in the prevalence of brucellosis (ranging from 1%–32%) has been reported in small ruminant populations of different parts of the world [ 8 – 10 ], and various socio-cultural and management/husbandry practices have been reported to contribute to this varying prevalence in small ruminants [ 4 ]. Control of brucellosis largely depends on intensive screening and surveillance of the illness, both in animals and humans.…”