Infectious Disease Surveillance Center, National Institute of Infectious Diseases, 1-23-1 Toyama, Shinjuku-ku, Tokyo, 162-8640, Japan.
Infectious Disease Surveillance Center, National Institute of Infectious Diseases, 1-23-1 Toyama, Shinjuku-ku, Tokyo, 162-8640, Japan.
J Infect Chemother. 2020 Nov;26(11):1146-1151. doi: 10.1016/j.jiac.2020.06.005. Epub 2020 Jul 2.
Shigellosis cases have decreased gradually in Japan in recent years, but indigenous shigellosis outbreaks sometimes occur in childcare facilities. From national surveillance data, we identified a shigellosis outbreak involving a kindergarten.
After detecting Shigella sonnei in Kitakyushu City, we conducted active case finding and epidemiological investigation in Kindergarten Z, including stool specimen collection and interviews. The stool specimens were cultured, and isolated strains were subjected to pulsed-field gel electrophoresis (PFGE) and multiple-locus variable-number tandem-repeat analysis (MLVA).
Between September 1 and December 31, 2014, we identified 19 cases: 14 confirmed, 2 suspected, and 3 asymptomatic. Of the 19 cases, 16 were epidemiologically associated with Kindergarten Z (10 pupils, 5 family members, and 1 teacher). On October 19, a pupil with gastrointestinal illness participated in the kindergarten's sports festival, in which the pupils were split into "red" and "white" teams; the pupil in question belonged to the red team. Attack rates of the red and white teams were 8% (7/82) and 0% (0/108), respectively (relative risk, 10.5; 95% confidence interval, 1.3-82.1). PFGE patterns were identical or similar for the isolates in all 17 cases; 7 isolates were identical, and the others had one locus difference on MLVA.
We concluded that contact during the sports festival could have been responsible for spread of the shigellosis outbreak at the kindergarten, although the infection source was not determined. It is vital to inform guardians immediately after detection of shigellosis cases that symptomatic pupils should not participate in activities such as sports festivals.
近年来，日本的志贺菌病病例逐渐减少，但在儿童保育设施中偶尔会发生本土志贺菌病暴发。从国家监测数据中，我们确定了一起涉及幼儿园的志贺菌病暴发。
在检测到北九州市的宋内志贺菌后，我们对幼儿园 Z 进行了主动病例发现和流行病学调查，包括采集粪便标本和访谈。对粪便标本进行培养，并对分离株进行脉冲场凝胶电泳（PFGE）和多位点可变数目串联重复分析（MLVA）。
2014 年 9 月 1 日至 12 月 31 日，我们共发现 19 例病例：14 例确诊，2 例疑似，3 例无症状。19 例病例中，有 16 例与幼儿园 Z 有流行病学关联（10 名学生、5 名家庭成员和 1 名教师）。10 月 19 日，一名患有胃肠道疾病的学生参加了幼儿园的运动会，学生们被分为“红”队和“白”队；问题学生属于红队。红队和白队的发病率分别为 8%（7/82）和 0%（0/108）（相对风险，10.5；95%置信区间，1.3-82.1）。17 例病例中的所有分离株的 PFGE 模式相同或相似；7 株分离株完全相同，其余株在 MLVA 上有一个位点差异。
我们得出结论，在运动会期间的接触可能是导致幼儿园志贺菌病暴发的原因，尽管感染源尚未确定。在检测到志贺菌病病例后，立即通知监护人，患有症状的学生不应参加运动会等活动，这一点至关重要。
