In Hyderabad, Pakistan, an outbreak of extensively drug-resistant (XDR) Salmonella enterica ssp. enterica serovar Typhi, resistant to chloramphenicol, ampicillin, trimethoprim–sulfamethoxazole, fluoroquinolones, and third-generation cephalosporins, was recognized in November 2016 and has now spread to Karachi, home to more than 14 million people. More than 1000 cases have been confirmed by blood culture; since most typhoid cases are treated empirically, however, the true number of cases is probably many times greater. The outbreak is being caused by the H58 clade, a multidrug-resistant haplotype of S. Typhi that is common in Asia and areas of Africa. The H58 S. Typhi involved in the outbreak contains a chromosomally integrated antimicrobial-resistance cassette imparting resistance to chloramphenicol, ampicillin, and trimethoprim–sulfamethoxazole, and the XDR variant also contains an IncY plasmid that carries not only the fluoroquinolone-resistance gene qnrS but also the CTX-M-15 gene bla that mediates resistance to ceftriaxone.¹ S. Typhi already causes invasive disease in 12 million to 22 million people each year, many of whom live in South and Southeast Asia, and the emergence of an XDR variant in this densely populated area is extremely worrisome.²

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广泛抗药性伤寒-共轭疫苗是否及时到货？

在巴基斯坦海得拉巴，爆发了广泛耐药的沙门氏菌沙门氏菌。肠型血清型伤寒，对氯霉素，氨苄青霉素，甲氧苄氨嘧啶，磺胺甲恶唑，氟喹诺酮和第三代头孢菌素具有抗药性，于2016年11月得到认可，现已传播到拥有超过1400万人的卡拉奇。血培养确诊了1000多例；由于大多数伤寒病例都是凭经验治疗的，因此实际病例数可能要大很多倍。爆发是由H58进化枝引起的，H58进化枝是S的多药耐药单倍型。在亚洲和非洲地区常见的伤寒。H58 S。参与暴发的鼠伤寒含有染色体整合的抗药性盒，对氯霉素，氨苄青霉素和甲氧苄氨嘧啶-磺胺甲恶唑具有抗性，XDR变体还包含一个IncY质粒，该质粒不仅携带抗氟喹诺酮抗性基因qnrS，而且携带CTX-M -15基因bla介导对头孢曲松的耐药性。^1和 小号。伤寒已经导致每年1200万至2200万人的侵袭性疾病，其中许多人生活在南亚和东南亚，在这个人口稠密的地区出现了XDR变种，这非常令人担忧。^2个