Epidemiological study for repeated outbreak of anthrax and identification of Bacillus anthracis

Epidemiological study for repeated outbreak of anthrax and identification of Bacillus anthracis in soils and animal samples by culture free technique in Bangladesh
KHMNH Nazir¹, MM Islam¹, MM Mahmud¹, MA Islam¹, SMZH Chowdhury², MR Islam², MB Rahman<sup>1

1</sup>Department of Microbiology and Hygiene, Bangladesh Agricultural University, Mymensingh-2202, Bangladesh.

²Bangladesh Agricultural Research Council, Farmgate, Dhaka, Bangladesh.
Corresponding author’s affiliation and e-mail address: Prof. KHM Nazmul Hussain Nazir, Department of Microbiology and Hygiene, Bangladesh Agricultural University, Mymensingh-2202, Bangladesh.

E-mail: [e-mail]

The research work was aimed at epidemiological study of repeated outbreak of anthrax in Bangladesh and identification of Bacillus anthracis by culture free identification technique. A cross-sectional survey was employed during January to July 2016 to investigate awareness, attitudes and management practice towards anthrax outbreaks in Bangladesh. Administrative areas of Bangladesh have been divided into high (Kushtia), medium (Pabna), and low risk (Mymensingh) anthrax areas based on the reports published in daily newspapers and scientific journals. A total of 622 people in the selected areas were interviewed using structured questionnaire and the collected data were uploaded into ‘Magpi’ data collection tool. The data were analyzed using Epi Info™. Soil samples (n=129) from the study areas were collected and DNA from the soils were extracted by using soil DNA extraction kit. The DNA samples were subjected for molecular detection of B. anthracis targeting Cap (pX02 plasmid), Sap (specific for B. anthracis) and Pag (pX01 plasmid) genes. Among the interviewers, about half of the total people (46.46%; n=289/622) were illiterate, which was worse in Kushtia and Pabna. Farmers from Kushtia were more aware to anthrax as compared to those from low and medium risk areas. Knowledge on zoonoses of anthrax and lack of vaccination were also very poor among people of low and medium risk areas. For the treatment of diseased animals, most farmers (about 98%) at high and low risk areas depended on village doctors. Among the 129 soil samples, the viable B. anthracis spores could be extracted from 21 (16.3%) samples. All the 21 soil samples were confirmed for the presence of Sap gene of B. anthracis showing 639-bp target size in gel elecrophoresis. Both pX01 and pX02 plasmids were harbored in 3 isolates. On the other hand, only pX01 (target size 596-bp) was present in 11 isolates. And, only pX02 (target size 846-bp) was present in 7 isolates. The qualitative study revealed that lack of vaccination and unawareness were the main causes of repeated outbreak of anthrax in Bangladesh.