Chirwa Esmeda B, Dale Helen, Gordon Melita A, Ashton Philip M
Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, Liverpool, United Kingdom.
Salmonella group, Malawi Liverpool Wellcome Programme, Blantyre, Malawi.
Open Forum Infect Dis. 2023 Feb 20;10(3):ofad086. doi: 10.1093/ofid/ofad086. eCollection 2023 Mar.
Invasive nontyphoidal (iNTS) disease is a clinical condition distinct from gastroenteritis. With an overall case-fatality rate of 14.5%, iNTS remains a major cause of morbidity and mortality, particularly in sub-Saharan Africa. However, the sources of infections that lead to cases of iNTS remain unclear. Broadly, there are 2 hypotheses as to the source of infections: () transmission from a zoonotic reservoir, similar to other nontyphoidal salmonelloses; or () person-to-person transmission. Here we review several recent studies that have asked, "What is the source of infections causing invasive nontyphoidal disease?" Two studies reported isolates in the stool of household members of iNTS cases that were very closely related (<3 single-nucleotide polymorphisms) to the iNTS case isolates; this is consistent with the hypothesis of person-to-person transmission, but infection from a common source (eg, a foodstuff) cannot be excluded. On the other hand, thorough investigations of the domestic environment of iNTS cases and the food pathway found only a single iNTS-associated Enteritidis isolate. Therefore, we recommend that future studies test the hypothesis that iNTS is transmitted between people within the domestic environment. Further studies of food and water pathways are also warranted.
侵袭性非伤寒（iNTS）疾病是一种与肠胃炎不同的临床病症。iNTS的总体病死率为14.5%，仍然是发病和死亡的主要原因，尤其是在撒哈拉以南非洲地区。然而，导致iNTS病例的感染源仍不明确。大体上，关于感染源有两种假说：（1）来自动物宿主的传播，类似于其他非伤寒沙门氏菌病；或（2）人传人传播。在此，我们回顾了最近几项探讨“导致侵袭性非伤寒疾病的感染源是什么？”的研究。两项研究报告称，iNTS病例家庭成员粪便中的分离株与iNTS病例分离株密切相关（<3个单核苷酸多态性）；这与人传人传播假说相符，但不能排除来自共同来源（如一种食物）的感染。另一方面，对iNTS病例的家庭环境和食物路径进行的深入调查仅发现了一株与iNTS相关的肠炎沙门氏菌分离株。因此，我们建议未来的研究检验iNTS在家庭环境中人际传播的假说。对食物和水路径的进一步研究也很有必要。
