艾滋病流行诱发非洲沙门氏菌出现新品种

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源：科技日报
  
    最近，英国科学家在非洲艾滋病病毒感染者体内发现了一种沙门氏菌新品种，该菌株具有多重抗药性，一旦感染极难治疗。科学家认为，该菌株的出现是艾滋病在非洲流行的结果。这项研究成果发表在近期的《临床传染病》杂志上。
　　英国利物浦大学和维康基金会桑格研究所的研究人员发现，在非洲成年艾滋病病毒感染者体内，这种新型非洲沙门氏菌能够入侵到血液和骨髓细胞内，引起严重的疾病。它们会在细胞中潜伏下来并不断演化，从而更具耐药性，更危险。这意味着一旦感染该病菌则很难治疗，且会经常复发，而这复发的过程会使这些细菌更具适应性和耐药性。
　　在欧美等地，沙门氏菌会导致腹泻，但很少致命。而在非洲，无论是对成人还是儿童，这种新型的具有多重抗药性的病菌都十分危险，四分之一的感染者最后会死亡。　　科学家认为，这种新菌株的出现是非洲大陆艾滋病流行的结果。利物浦大学的梅丽塔·戈登博士指出，正是非洲艾滋病和其他一些影响人体免疫系统的疾病的流行，为新的、更危险的病菌的出现提供了合适的环境。
　　下一步，研究人员将研究如何在不引发新的抗生素耐药性的前提下更好地治疗这种病菌感染，同时他们也希望通过使用新的遗传标记来更有效地跟踪和了解非洲沙门氏菌的习性和传播方式。

ligouxiang

   哪到底是哪种沙门氏菌，按目前分类中难道没有吗？是否会是新的品种？不知是否有这方面的资料。

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nvasive Non-typhoid Salmonellae Establish Systemic Intracellular Infection in HIV-Infected Adults: An Emerging Disease Pathogenesis
Clinical Infectious Diseases 2010;50:953–962
Salmonellae are facultative intracellular pathogens. Non-typhoid salmonellae (NTS) cause self-limiting mucosal disease in immunocompetent adults but invasive, recurrent disease among human immunodeficiency virus (HIV)–infected adults in Africa. The importance of intracellular NTS infection in HIV is unknown.
Methods.We performed quantitative pour-plate culture of blood samples obtained during febrile events among 495 Malawian adults on 871 occasions, and NTS were isolated at 158 events. Ninety-eight percent were HIV infected, with a median CD4 count of 67 cells/μL. Lysis of pour plates and gentamicin exclusion testing were used to investigate the presence of intracellular NTS in blood and bone marrow.

Results.Total viable NTS counts in blood were low (1 colony-forming unit [CFU]/mL) but correlated independently with lower CD4 count and with IL-10 and IL-6 levels, especially at recurrence, suggesting failure to clear intracellular infection. Viable NTS load in blood and bone marrow were closely correlated at index events, but NTS were significantly concentrated in bone marrow, compared with blood samples, at recurrences (6 vs 1 CFU/mL), suggesting systemic tissue replication. Both lysis-pour-plating and gentamicin exclusion testing demonstrated intracellular infection with >1 CFU/cell in both blood and bone marrow specimens. Intracellular bacteria were demonstrated in bone marrow at both index and recurrent events, showing that this is an early and enduring feature of pathogenesis, but intracellular NTS were detected in blood only at index events, particularly in patients with a CD4 count <50 cells/μL. Intravascular NTS at recurrence may therefore reflect extracellular “overspill” from an intracellular sanctuary site, following failure of immunological control.
Conclusions.Invasive NTS have established a new and emerging pathogenesis in the context of HIV infection in Africa.

三把手

种沙门氏菌新品种是否全耐药，如果是的话，艾滋病病人一旦感染上将是必死无疑了！-----恐怖！

琪琪5

路过学习了，谢谢老师的分享