Analysis of epidemic characteristics of anthrax in China from 2017 to 2019 and molecular typing of Bacillus anthracis / 中华预防医学杂志

ABSTRACT

Objective: To analyze the epidemiological characteristics of anthrax in China from 2017 to 2019 and molecular typing of Bacillus anthracis isolated from some provinces (autonomous regions). Methods: Surveillance data of anthrax cases reported from 2017 to 2019 in the Infectious Disease Surveillance information System of China Disease Prevention and Control and the Public Health Emergency Reporting and Management Information System were collected, and descriptive epidemiological methods were used to analyze the epidemic characteristics, including the temporal, geographic and demographic distribution of this disease. A total of 47 strains of Bacillus anthracis isolated from 2017 to 2019 were analyzed by canSNP and MLVA15. Results: A total of 951 cases of anthrax were reported from 2017 to 2019, of which 938 were cutaneous anthrax, representing 98.63% of the total number reported. It was mainly distributed in the west and northeast of China, and the three provinces with the highest number of cases were Gansu (215), Sichuan (202) and Qinghai (191). Cases had been reported throughout the year, more cases occurred in the summer and autumn, and August was the month with the most cases,66.35% (211/318), 72.32% (243/336) and 68.01% (202/297) of cases were reported during June to September. The age distribution was mainly between 20 and 59 years old, accounting for more than 80% of all cases. The number of male cases was significantly higher than that of female cases, the ratio of male to female was about 3∶1. The occupations were mainly herdsmen and farmers, accounting for 49.70% to 58.18% and 31.45% to 36.70%, respectively. Public health events occurred every year, and 29 events had been reported from 2017 to 2019. canSNP analysis showed that 37 of the 47 strains belonged to the A.Br.001/002 subgroup and 10 belonged to the A.Br.Ames subgroup. MLVA15 analysis showed that there were 17 genotypes, of which 10 genotypes contained only one strain. Conclusion: Cutaneous anthrax was the predominant clinical type in China from 2017 to 2019.The seasonal, geographic and demographic distribution characteristics were evident.Molecular typing methods such as canSNP and MLVA15 can be used to trace the source of infectious diseases and provide technical support for anthrax prevention and control.