Journal of Pure and Applied MicrobiologyVol. 9 No. 1

Incidence and Enterotoxin Gene Profile of Bacillus cereus Strains Isolated from Human Stool Samples from Uttarakhand, India

Anita Tewari* and S.P. Singh

Department of Veterinary Public Health and Epidemiology, Collage of Veterinary and Animal Sciences, Govind Ballabh Pant University of Agriculture and Technology, Pantnagar, Distt. U. S. Nagar -263145, India.

Received on 20 December 2014 and accepted on 15 January 2015



The present investigation was undertaken to study the incidence and enterotoxigenic profile of Bacillus cereus in human stool samples. A total of 311 stool samples of apparently healthy human were collected and screened for the presence of B. cereus. Recovered B. cereus isolates were confirmed by PCR for gyrB gene and further evaluated for enterotoxin genes. Organism was isolated from 23 samples making the percent incidence of 7.4%. Screening of isolates by multiplex polymerase chain reaction revealed the overall distribution of various enterotoxin genes hblDAC complex, nheABC complex, cytK and entFM as 39.1, 95.6, 69.5 and 100%, respectively. Incidence rate (7.4%) was found low in population but majority of isolates harboring all the enterotoxin genes. B. cereus isolates of human stool origin were found to be strongly hemolytic and showed the presence of at least two enterotoxigenic genes. B. cereus is a very common food borne pathogen but a very limited data are available regarding the enterotoxin gene profile of B. cereus strains isolated from human stool. The presence of large number of enterotoxigenic B. cereus strains in stool samples must be considered as a potential health hazard as well as a source of contamination to environment.

Keywords : Bacillus cereus; enterotoxin gene; human stool; Incidence.