Hammond-Collins Karon, Strauss Barbara, Barnes Kirsten, Demczuk Walter, Domingo Marc-Christian, Lamontagne Marie-Christine, Lu Diane, Martin Irene, Tepper Martin
Canadian Field Epidemiology Program, Public Health Agency of Canada, 100 Colonnade Drive, Ottawa, ON, Canada.
Directorate of Force Health Protection, Canadian Forces Medical Group Headquarters, Carling Campus, 101 Colonel By Drive, Ottawa, ON, Canada.
Mil Med. 2019 Mar 1;184(3-4):e197-e204. doi: 10.1093/milmed/usy198.
Between December 2016 and April 2017, two cases of invasive Group A Streptococcus (GAS) infections were reported at a Canadian military training facility. An outbreak was declared and a field investigation was launched to characterize the outbreak and identify associated risk factors to limit transmission. Throat culture data from military personnel at the garrison were analyzed. Investigators tracked invasive GAS cases and non-invasive hospitalized GAS cases, and conducted site visits and case interviews. Sensitivity and specificity for a rapid antigen detection test were evaluated. Molecular typing and phylogenomic relationships of outbreak isolates were analyzed using whole-genome sequencing. During this outbreak, four invasive cases were reported and six non-invasive cases were hospitalized. In a sample of 705 throat cultures examined, 35.2% were GAS-positive. Among 65 platoon contacts of one invasive case, 30.2% were GAS-positive. Reluctance to seek medical care, challenges in following cough etiquette, and low compliance with antibiotics were identified among recruits. The rapid antigen detection test had low sensitivity (31.6%) during the outbreak. The outbreak sequence type was emm6.4 and outbreak isolates were highly related phylogenetically, differing by 0-4 single nucleotide variants. This is the first report of a GAS outbreak among Canadian military trainees. Increased surveillance of GAS infections, increased control measures and outbreak-specific clinical guidelines were implemented in-garrison. No further invasive GAS cases were identified. A GAS surveillance system was implemented and efforts to improve antibiotic compliance and medical consultation were recommended.
2016年12月至2017年4月期间，加拿大一个军事训练基地报告了两例侵袭性A组链球菌（GAS）感染病例。宣布爆发疫情并展开实地调查，以描述疫情特征并确定相关风险因素以限制传播。对驻军军事人员的咽喉培养数据进行了分析。调查人员追踪侵袭性GAS病例和非侵袭性住院GAS病例，并进行了实地考察和病例访谈。评估了快速抗原检测试验的敏感性和特异性。使用全基因组测序分析了疫情分离株的分子分型和系统发育关系。在此次疫情期间，报告了4例侵袭性病例，6例非侵袭性病例住院治疗。在检查的705份咽喉培养样本中，35.2%为GAS阳性。在一名侵袭性病例的65名排级接触者中，30.2%为GAS阳性。新兵中存在不愿就医、遵守咳嗽礼仪方面的挑战以及抗生素依从性低的问题。疫情期间快速抗原检测试验的敏感性较低（31.6%）。疫情序列类型为emm6.4，疫情分离株在系统发育上高度相关，单核苷酸变异相差0 - 4个。这是加拿大军事学员中GAS疫情的首次报告。驻军实施了加强GAS感染监测、增加控制措施和针对疫情的临床指南。未发现进一步的侵袭性GAS病例。实施了GAS监测系统，并建议努力提高抗生素依从性和医疗咨询。
