Guerrero L, Calva J J, Morrow A L, Velazquez F R, Tuz-Dzib F, Lopez-Vidal Y, Ortega H, Arroyo H, Cleary T G, Pickering L K
Department of Infectious Diseases, Instituto Nacional de la Nutrición, Mexico City, Mexico.
Pediatr Infect Dis J. 1994 Jul;13(7):597-602. doi: 10.1097/00006454-199407000-00003.
The proportion of Shigella infections that occur asymptomatically in young children has not been established. A community-based cohort study of 367 infants was followed prospectively by weekly home visits from January, 1990, through December, 1991. Stool samples were collected weekly and when diarrhea occurred and were tested for Shigella and other enteropathogens. There were 2925 child months of observation and 65 episodes of Shigella infection. There were 3.1 episodes/100 child months during the warm season (May through September) and 0.97 episode/100 child months during the cold season. Shigella infections were rare during the first 6 months of life but increased with age (P < 0.0001). Overall 55% of detected infections were asymptomatic. The proportion of infections that were asymptomatic increased as age increased (P < 0.01). Symptom status was not significantly associated with Shigella species or season. All isolates from symptomatic and asymptomatic children had the 120- to 140-megadalton virulence plasmid. We conclude that infections with virulent strains of Shigella are commonly asymptomatic in Mexican children during the first 2 years of life.
幼儿中无症状志贺菌感染的比例尚未确定。1990年1月至1991年12月，对367名婴儿进行了一项基于社区的队列研究，通过每周上门随访进行前瞻性跟踪。每周收集粪便样本，并在腹泻发生时收集，检测其中的志贺菌和其他肠道病原体。共进行了2925个儿童月的观察，发现65例志贺菌感染。温暖季节（5月至9月）的感染率为3.1例/100儿童月，寒冷季节为0.97例/100儿童月。志贺菌感染在生命的前6个月很少见，但随年龄增长而增加（P<0.0001）。总体而言，55%的检测到的感染是无症状的。无症状感染的比例随年龄增长而增加（P<0.01）。症状状态与志贺菌种类或季节无显著关联。有症状和无症状儿童的所有分离株都有120至140兆道尔顿的毒力质粒。我们得出结论，在墨西哥儿童生命的前两年中，感染有毒力的志贺菌菌株通常是无症状的。
