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Original article https://doi.org/10.12980/apjtd.7.2017D7-62 ©2017 by the Asian Pacific Journal of Tropical Disease. All rights reserved.
Epidemiological and laboratory investigation of a zoonotic anthrax outbreak in West Bengal, India
Premanshu Dandapat
1*
, Arijit Chakrabarty
1
, Sonjoy Dey
2
, Pramod Kumar Nanda
1
, Suresh Chandra Das
1
, Suman Dey
3
, Arun Kurien
4
, Apurba
Chakraborty
5
, Samiran Bandyopadhyay
1
, Subhasish Bandyopadhyay
1
, Raj Kumar Singh
6
1
Eastern Regional Station, ICAR-Indian Veterinary Research Institute, 37, Belgachia Road, Kolkata, PIN 700 037, West Bengal, India
2
Department of Paediatrics, Bankura Sammilani Medical College & Hospital, P.O.: Kenduadihi, Dist.: Bankura, PIN – 722 102, West Bengal, India
3
Animal Resources Development (Veterinary Research & Investigation), Toxicology Laboratory, Jhargram, Dist: West Midnapur, PIN 721 507, West Bengal,
India
4
Department of Animal Husbandry, Mattukatta, Idukki, PIN 685 584, Kerala, India
5
Midnapur Sadar Block, Village Satgerya, P.O. Pachkhuri, Dist: West Medinipur, Pin: 721 150, West Bengal, India
6
ICAR-Indian Veterinary Research Institute, Izatnagar, Bareilly, PIN 243 122, Uttar Pradesh, India
Asian Pac J Trop Dis 2017; 7(11): 653-658
Asian Pacific Journal of Tropical Disease
journal homepage: http://www.apjtcm.com
*Corresponding author: Premanshu Dandapat, Senior Scientist, Eastern Regional
Station, ICAR-Indian Veterinary Research Institute, 37, Belgachia Road, Kolkata,
PIN 700 037, India.
Tel: +91-33-25565725
E-mail: pdandapat@gmail.com
Foundation Project: Supported by the Indian Council of Agricultural Research,
New Delhi under the project AICRP on ADMAS (Grant No. AS/14/1/2013/ASR-IV).
The journal implements double-blind peer review practiced by specially invited
international editorial board members.
1. Introduction
Amongst important zoonotic diseases reported till date,
anthrax is a fatal infectious disease and has a nearly worldwide
distribution. It is caused by Bacillus anthracis (B. anthracis), a
capsulated non-motile, aerobic, Gram positive and spore forming
organism. Although almost all mammals including domestic and
wild herbivores (such as cattle, sheep, goats, bison, deer, antelope
and hippos) are affected by anthrax, higher mortality is recorded in
ruminants[1-3]. Outbreaks of anthrax in animals mostly occur due
to exposure to contaminated soil or ingestion of bacillus spores
adhering to vegetation during grazing[4]. Because of the disease,
infected animals not only loose body weight with reduced milk
yield, but also collapse and die induced by high fever, breathing
problems and presence of blood in the urine, faeces or milk[5].
A study conducted in India (1991–2005) estimates the average
annual economic loss in cattle due to anthrax at 1.3%[6], which is
ARTICLE INFO ABSTRACT
Objective: To investigate an anthrax outbreak affecting multi-species of animals including
human in five remote tribal villages in West Midnapur district, India, with no previous history
of anthrax cases for decades.
Methods: A systematic epidemiological investigation, along with bacteriological examination,
cultural isolation, biochemical and molecular characterization of the samples (blood, dried
meat, pieces of bones) was carried out to confirm diagnosis, identify transmission routes and
risk factors to recommend suitable control measures.
Results: Samples from nine animals were confirmed for presence of Bacillus anthracis by
characteristic morphology, biochemical profile, McFadyean reaction in blood smear, ‘medusa
head’ appearance of colonies and PCR based detection of pXO1 plasmid. Epidemiological
investigation revealed that the human patients contracted the infection during butchering or
while handling contaminated animal products. In total, 14 animals died and 11 people got
infected with cutaneous anthrax during the outbreak period.
Conclusions: Anthrax continues to be a persisting problem in Indian subcontinent causing
considerable morbidity and mortality in animals and human. Collaborative efforts of human
and animal health officials through various controlled measures viz., ring vaccination, early
treatment of human cases, quarantine of affected animals, safe disposal of carcass and public
health campaign effectively controlled the zoonotic anthrax outbreak.
Article history:
Received 5 Apr 2017
Received in revised form 15 May, 2nd
revised form 31 May 2017
Accepted 20 Aug 2017
Available online 24 Oct 2017
Keywords:
Anthrax
Epidemiology
India
West Bengal
Zoonotic