Third Wave of Influenza A(H7N9) Virus from Poultry,Guangdong Province,China, 2014–2015

Fourteen influenza A(H7N9) viruses were isolated from poultry or the environment in live poultry markets in Guangdong Province, China during 2014−2015. Phylogenetic analysis showed that all viruses were descended from viruses of the second wave of influenza A(H7N9) virus infections during 2013. These viruses can be divided into 2 branches.     

Use of National Pneumonia Surveillance to Describe Influenza A(H7N9) Virus Epidemiology,China, 2004–2013

In mainland China, most avian influenza A(H7N9) cases in the spring of 2013 were reported through the pneumonia of unknown etiology (PUE) surveillance system. To understand the role of possible underreporting and surveillance bias in assessing the epidemiology of subtype H7N9 cases and the effect of live-poultry market closures, we examined all PUE cases reported from 2004 through May 3, 2013. Historically, the PUE system was underused, reporting was inconsistent, and PUE reporting was biased toward A(H7N9)-affected provinces, with sparse data from unaffected provinces; however, we found no evidence that the older ages of persons with A(H7N9) resulted from surveillance bias. The absolute number and the proportion of PUE cases confirmed to be A(H7N9) declined after live-poultry market closures (p<0.001), indicating that market closures might have positively affected outbreak control. In China, PUE surveillance needs to be improved.     

Poultry Market Closures and Human Infection with Influenza A(H7N9) Virus,China, 2013–14

Closure of live poultry markets was implemented in areas affected by the influenza virus A(H7N9) outbreak in China during winter, 2013–14. Our analysis showed that closing live poultry markets in the most affected cities of Guangdong and Zhejiang provinces was highly effective in reducing the risk for H7N9 infection in humans.     

Increased Number of Human Cases of Influenza Virus A(H5N1) Infection,Egypt, 2014–15

During November 2014–April 2015, a total of 165 case-patients with influenza virus A(H5N1) infection, including 6 clusters and 51 deaths, were identified in Egypt. Among infected persons, 99% reported poultry exposure: 19% to ill poultry and 35% to dead poultry. Only 1 person reported wearing personal protective equipment while working with poultry.     

Reassortant Avian Influenza A(H9N2) Viruses in Chickens in Retail Poultry Shops,Pakistan, 2009–2010

Phylogenetic analysis of influenza viruses collected during December 2009–February 2010 from chickens in live poultry retail shops in Lahore, Pakistan, showed influenza A(H9N2) lineage polymerase and nonstructural genes generate through inter- and intrasubtypic reassortments. Many amino acid signatures observed were characteristic of human isolates; hence, their circulation could enhance inter- or intrasubtypic reassortment.     

Timing of Influenza A(H5N1) in Poultry and Humans and Seasonal Influenza Activity Worldwide, 2004–2013

Co-circulation of influenza A(H5N1) and seasonal influenza viruses among humans and animals could lead to co-infections, reassortment, and emergence of novel viruses with pandemic potential. We assessed the timing of subtype H5N1 outbreaks among poultry, human H5N1 cases, and human seasonal influenza in 8 countries that reported 97% of all human H5N1 cases and 90% of all poultry H5N1 outbreaks. In these countries, most outbreaks among poultry (7,001/11,331, 62%) and half of human cases (313/625, 50%) occurred during January–March. Human H5N1 cases occurred in 167 (45%) of 372 months during which outbreaks among poultry occurred, compared with 59 (10%) of 574 months that had no outbreaks among poultry. Human H5N1 cases also occurred in 59 (22%) of 267 months during seasonal influenza periods. To reduce risk for co-infection, surveillance and control of H5N1 should be enhanced during January–March, when H5N1 outbreaks typically occur and overlap with seasonal influenza virus circulation.     

Zoonotic Transmission of Avian Influenza Virus (H5N1), Egypt, 2006�C2009

During March 2006–March 2009, a total of 6,355 suspected cases of avian influenza (H5N1) were reported to the Ministry of Health in Egypt. Sixty-three (1%) patients had confirmed infections; 24 (38%) died. Risk factors for death included female sex, age >15 years, and receiving the first dose of oseltamivir >2 days after illness onset. All but 2 case-patients reported exposure to domestic poultry probably infected with avian influenza virus (H5N1). No cases of human-to-human transmission were found. Greatest risks for infection and death were reported among women >15 years of age, who accounted for 38% of infections and 83% of deaths. The lower case-fatality rate in Egypt could be caused by a less virulent virus clade. However, the lower mortality rate seems to be caused by the large number of infected children who were identified early, received prompt treatment, and had less severe clinical disease.     

Monitoring Avian Influenza A(H7N9) Virus through National Influenza-like Illness Surveillance,China

In China during March 4–April 28, 2013, avian influenza A(H7N9) virus testing was performed on 20,739 specimens from patients with influenza-like illness in 10 provinces with confirmed human cases: 6 (0.03%) were positive, and increased numbers of unsubtypeable influenza-positive specimens were not seen. Careful monitoring and rapid characterization of influenza A(H7N9) and other influenza viruses remain critical.     

我国H7N9禽流感病毒血凝素和神经氨酸酶基因的分子进化分析

  目的  通过对安徽省安庆市人感染H7N9禽流感外环境标本检测,分析外环境中病毒污染情况,研究判断人感染H7N9的风险,为制定防控措施提供依据。  方法  于2017年1月5日 — 2月22日,采用完全随机抽样的方法,采集安庆市38家农贸市场、4例确诊人感染H7N9禽流感病例居家禽类相关标本共324份,用实时荧光定量RT-PCR方法进行甲型流感病毒通用核酸检测,对阳性标本进一步进行H7N9检测。  结果  安庆市H7N9禽流感病毒阳性率28.40 %,11个县（市、区）中有10个检出H7N9病毒阳性,阳性率90.90 % （10/11）。主城区阳性率37.68 %（26/69）高于非主城区,差异有统计学意义（χ² = 9.23,P < 0.05）;鸡、鸭、鸽子标本中,鸡标本阳性率最高31.75 %（80/252）,差异有统计学意义（χ² = 6.57,P < 0.05）;农贸市场来源的标本阳性率为29.77 %（92/309）,病例家来源的标本阳性率为0,差异有统计学意义（χ² = 6.24,P < 0.05）;不同类型标本中,咽拭子和肛拭子阳性率最高,分别为42.86 %（9/21）和40.00 %（2/5）,其次为饮水和污水;发生人感染病例前外环境标本阳性率38.71 %（12/31）高于发生后,但2者间的差异无统计学意义（χ² = 1.79,P > 0.05）。  结论  安庆市农贸市场存在H7N9禽流感病毒污染。     

Surveillance for Avian Influenza A(H7N9), Beijing,China, 2013

During surveillance for pneumonia of unknown etiology and sentinel hospital–based surveillance in Beijing, China, we detected avian influenza A(H7N9) virus infection in 4 persons who had pneumonia, influenza-like illness, or asymptomatic infections. Samples from poultry workers, associated poultry environments, and wild birds suggest that this virus might not be present in Beijing.     

Clinical Findings for Early Human Cases of Influenza A(H7N9) Virus Infection,Shanghai, China

A novel strain of influenza A(H7N9) virus has emerged in China and is causing mild to severe clinical symptoms in infected humans. Some case-patients have died. To further knowledge of this virus, we report the characteristics and clinical histories of 4 early case-patients.     

成都市首例人感染H9N2禽流感病例调查与分析

  目的   将从世界卫生组织发布的人兽共患病报告,以及PubMed、中国知网、和万方等数据库中检索到的全球自2016 — 2021年人感染H9N2的相关报道进行整理和汇总,再结合H9N2禽流感病毒的血清学监测结果对其感染人的风险进行评估,从基因学的角度探索H9N2禽流感病毒跨屏障感染人的原因。研究发现人感染H9N2禽流感的病例呈上升趋势,环境中和人群中的血清学监测结果也呈现较高的阳性率;H9N2禽流感病毒基因组中病毒表面结构蛋白血凝素基因突变和聚合酶基因突变对于其感染人具有重要意义。     

Human Infection with Highly Pathogenic A(H7N7) Avian Influenza Virus,Italy, 2013

During an influenza A(H7N7) virus outbreak among poultry in Italy during August–September 2013, infection with a highly pathogenic A(H7N7) avian influenza virus was diagnosed for 3 poultry workers with conjunctivitis. Genetic analyses revealed that the viruses from the humans were closely related to those from chickens on affected farms.     

Mild Illness in Avian Influenza A(H7N9) Virus–Infected Poultry Worker,Huzhou, China,April 2013

During April 2013 in China, mild respiratory symptoms developed in 1/61 workers who had culled influenza A(H7N9) virus–infected poultry. Laboratory testing confirmed A(H7N9) infection in the worker and showed that the virus persisted longer in sputum than pharyngeal swab samples. Pharyngeal swab samples from the other workers were negative for A(H7N9) virus.     

深圳市19例人感染H7N9禽流感确诊病例流行病学分析

目的 分析广东省深圳市19例人感染H7N9禽流感病例的流行病学分布特征和规律,为制定疫情控制措施提供依据。方法 收集中国疾病预防控制信息系统2013年12月19日-2014年2月15日报告的深圳市19例人感染H7N9禽流感确诊病例进行流行病学分析。结果 19例人感染H7N9禽流感病例中,男性10例,女性9例,年龄6~82岁,中位数年龄为56岁,其中>40岁13例,占68.4%,以离退休人员和家务及待业者为主,分别占31.6%和26.3%,分别有47.4%和26.3%的病例分布于龙岗和罗湖区;19例病例中5例有直接禽鸟类接触史,11例病例有活禽市场接触史;共追踪管理密切接触者830人,其中医务人员密切接触者587人,无二代病例;19例确诊病例中死亡2例,病死率为10.5%,其中男性和女性各1例,年龄均>40岁。结论 中老年是人感染H7N9禽流感的主要易感人群;规范活禽交易是有效防控人感染H7N9禽流感的关键环节。