Epidemiological investigation of a cutaneous anthrax outbreak in Tongliao, Inner Mongolia, 2018

ObjectiveTo understand the epidemiological and transmission characteristics of a cutaneous anthrax outbreak in Tongliao of Inner Mongolia in 2018, discuss the diagnosis process of the anthrax cases and provide evidence for the prevention and control of cutaneous anthrax in the future.

MethodsThe field epidemiological investigation was conducted to analyze the time, area and population distributions, exposure history, contact mode, clinical features of the anthrax cases. Laboratory detections included pathogen isolation and identification, PCR and ELISA.

ResultsA total of 23 cutaneous anthrax cases were reported in the outbreak, which were all distributed in a natural village. The age of the cases ranged from 20 to 64 years. Most cases were aged 30–55 years, accounting for 91.30%, and most cases were farmers, accounting for 95.65%. The outbreak lasted for 23 d. Of the 10 confirmed cases, 7 showed positive PCR results. A strain of Bacillus anthracis was isolated and its virulent plasmid was detected by PCR.

ConclusionThe epidemiological characteristics of this outbreak was obvious. Dissection, stripping, slaughter of sick animals, and exposure to sick animals and its products were the risk factors for the onset of anthrax. The source of the outbreak was sick cow or sick sheep. The transmission route was direct contact. Farmers were at high-risk. Taking joint prevention and control measures was the key for timely control of the anthrax outbreak.