一起皮肤炭疽疫情的病原学确诊及基因型溯源

目的 调查分析一起皮肤炭疽的感染来源，分离鉴定病原菌进行基因溯源，为控制炭疽疫情提供依据。方法 对患者进行流行病学调查，了解染疫病死畜的来源及去向，对病死牲畜饲养场所进行环境卫生学调查，采集患者皮肤炭疽病灶拭子标本，密切接触者血样，病死牲畜圈舍土壤、饲料，出售的病死畜样本。进行炭疽杆菌荧光定量PCR试验，分离培养炭疽杆菌及血清学检测。对分离到的病原菌进行canSNP分型及MLVA15基因分型。结果 本起皮肤炭疽患者多次多点购入16头牛饲养贩卖，在牛死亡后解剖病死牛而感染皮肤炭疽，密切接触者无发病。在病畜屠宰场所土壤及售出的牛皮中分离到2株炭疽杆菌。canSNP分型为A.Br.001/002型，MLVA15分型为MLVA15 - CHN51型，该基因型在国内首次发现。结论 流动牲畜贩运人员是炭疽高危人群，首次在国内报道炭疽基因型MLVA15 - CHN51型，丰富了我国炭疽杆菌的基因库。

Etiological diagnosis and genotype tracing of an epidemic of cutaneous anthrax

To investigate and analyze the source of infection of a cutaneous anthrax, isolate and identify thepathogenic bacteria for genetic tracing, and to provide a basis for controlling the anthrax epidemic. Methods Anepidemiological investigation was conducted on a patient with cutaneous anthrax to understand the source and destination ofdead animals. Environmental hygiene investigation was carried out in places where dead animals were raised. Swab samplesof cutaneous anthrax lesions of patients, blood samples of close contacts, soil and feed of dead animals, and samples of deadanimals sold were collected. Quantitative PCR test, Bacillus anthracis isolation and serological testing were performed.CanSNP typing and MLVA15 genotyping were performed on the isolated pathogens. Results The present case of cutaneousanthrax was caused by multiple multipoint purchases of 16 cattle for breeding and trafficking, and the cattle were infectedwith cutaneous anthrax by dissecting the diseased cattle after death, with no illness in close contacts. Two strains of Bacillusanthracis were isolated from the soil in the slaughter site of sick animals and the cowhide sold. The canSNP typing is A.Br.001/002, and the MLVA15 typing is MLVA15-CHN51. This genotype was discovered for the first time in China. ConclusionLivestock traffickers are at high risk of anthrax. The discovery of new anthrax genotypes enriches the gene database ofBacillus anthracis of China