美国疾病控制与预防中心Shikha Garg团队对人类感染高致病性甲型H5N1禽流感病毒进行了流行病学分析。相关论文于2024年12月31日发表在《新英格兰医学杂志》。

高致病性禽流感甲型（H5N1）病毒在美国的奶牛和家禽中引起了广泛的感染，并有零星的人类病例。研究组描述了2024年3月至10月在美国发现的人类甲型（H5N1）病例的特征。使用与疾病控制和预防中心甲型（H5N1）流感亚型试剂盒的实验室结果相关的标准化病例报告表，来分析实验室确诊的甲型H5N1病毒感染者的数据。

在46例患者中，20例接触了受感染的家禽，25例接触了感染或可能感染的奶牛，1例未发现接触动物；该患者因非呼吸道症状住院，并通过常规监测检测到甲型（H5N1）病毒感染。在45例接触动物的患者中，中位年龄为34岁，所有患者均患有轻度甲型（H5N1）疾病；没有人住院，也没有人死亡。共有42名患者（93%）出现结膜炎，22名（49%）出现发烧，16名（36%）出现呼吸道症状；15例（33%）仅患有结膜炎。

16名有可用数据的患者的中位病程为4天（范围为1至8天）。大多数患者（87%）接受了奥司他韦治疗；奥司他韦在症状发作后中位2天开始使用。在97名与动物接触病患的家庭接触者中，没有发现其他病例。接触受感染动物的工人最常用的个人防护装备类型是手套（71%）、护目镜（60%）和口罩（47%）。

在迄今为止发现的病例中，甲型（H5N1）病毒通常会引起轻度疾病，主要是短期结膜炎，主要发生在接触受感染动物的美国成年人身上；大多数患者接受了及时的抗病毒治疗。没有发现人与人之间传播甲型H5N1病毒的证据。职业暴露人员的个人防护装备使用情况不佳，这表明需要采取额外的策略来降低暴露风险。

附：英文原文

Title: Highly Pathogenic Avian Influenza A(H5N1) Virus Infections in Humans

Author: Shikha Garg, Katie Reinhart, Alexia Couture, Krista Kniss, C. Todd Davis, Marie K. Kirby, Erin L. Murray, Sophie Zhu, Vit Kraushaar, Debra A. Wadford, Cara Drehoff, Allison Kohnen, Mackenzie Owen, Jennifer Morse, Seth Eckel, Jessica Goswitz, George Turabelidze, Steve Krager, Anna Unutzer, Emilio R. Gonzales, Cherissa Abdul Hamid, Sascha Ellington, Alexandra M. Mellis, Alicia Budd, John R. Barnes, Matthew Biggerstaff, Michael A. Jhung, Malia Richmond-Crum, Erin Burns, Tom T. Shimabukuro, Timothy M. Uyeki, Vivien G. Dugan, Carrie Reed, Sonja J. Olsen

Issue&Volume: 2024-12-31

Abstract:

Background

Highly pathogenic avian influenza A(H5N1) viruses have caused widespread infections in dairy cows and poultry in the United States, with sporadic human cases. We describe characteristics of human A(H5N1) cases identified from March through October 2024 in the United States.

Methods

We analyzed data from persons with laboratory-confirmed A(H5N1) virus infection using a standardized case-report form linked to laboratory results from the Centers for Disease Control and Prevention influenza A/H5 subtyping kit.

Results

Of 46 case patients, 20 were exposed to infected poultry, 25 were exposed to infected or presumably infected dairy cows, and 1 had no identified exposure; that patient was hospitalized with nonrespiratory symptoms, and A(H5N1) virus infection was detected through routine surveillance. Among the 45 case patients with animal exposures, the median age was 34 years, and all had mild A(H5N1) illness; none were hospitalized, and none died. A total of 42 patients (93%) had conjunctivitis, 22 (49%) had fever, and 16 (36%) had respiratory symptoms; 15 (33%) had conjunctivitis only. The median duration of illness among 16 patients with available data was 4 days (range, 1 to 8). Most patients (87%) received oseltamivir; oseltamivir was started a median of 2 days after symptom onset. No additional cases were identified among the 97 household contacts of case patients with animal exposures. The types of personal protective equipment (PPE) that were most commonly used by workers exposed to infected animals were gloves (71%), eye protection (60%), and face masks (47%).

Conclusions

In the cases identified to date, A(H5N1) viruses generally caused mild illness, mostly conjunctivitis, of short duration, predominantly in U.S. adults exposed to infected animals; most patients received prompt antiviral treatment. No evidence of human-to-human A(H5N1) transmission was identified. PPE use among occupationally exposed persons was suboptimal, which suggests that additional strategies are needed to reduce exposure risk.

DOI: NJ202412310000001

Source: https://www.nejm.org/doi/full/10.1056/NEJMoa2414610