Institute for Infectious Disease and Endemic Disease Control, Beijing Center for Disease Prevention and Control-CDC, Beijing, China.
PLoS One. 2012;7(11):e50770. doi: 10.1371/journal.pone.0050770. Epub 2012 Nov 30.
The continued spread of highly pathogenic avian influenza (HPAI) viruses of H5 and H7 subtypes and low pathogenic avian influenza (LPAI) viruses of H5, H7 and H9 subtypes in birds and the subsequent infections in humans pose an ongoing pandemic threat. It has been proposed that poultry workers are at higher risk of exposure to HPAI or LPAI viruses and subsequently infection due to their repeated exposure to chickens or domestic waterfowl. The aim of this study was to examine the seroprevalence of antibodies against H5, H7 and H9 viruses amongst duck-related workers in Beijing, China and the risk factors associated with seropositivity. In March, 2011, 1741 participants were recruited from (1) commercial duck-breeding farms; (2) private duck-breeding farms; and (3) duck-slaughtering farms. Local villagers who bred ducks in their backyards were also recruited. A survey was administered by face-to-face interview, and blood samples were collected from subjects for antibody testing against H5, H7 and H9 viruses. We found that none of the subjects were seropositive for either H5 or H7 viruses, and only 0.7% (12/1741) had antibody against H9. A statistically significant difference in H9 antibody seroprevalence existed between the various categories of workers (P = 0.005), with the highest figures recorded amongst the villagers (1.7%). Independent risk factors associated with seropositivity toinfection with H9 virus included less frequent disinfection of worksite (OR, 5.13 [95% CI, 1.07-24.58]; P = 0.041; ≤ twice monthly versus>twice monthly) and handling ducks with wounds on hands (OR, 4.13 [95% CI, 1.26-13.57]; P = 0.019). Whilst the risk of infection with H5, H7 and H9 viruses appears to be low among duck-related workers in Beijing, China, ongoing monitoring of infection with the H9 virus is still warranted, especially amongst villagers who breed backyard ducks to monitor for any changes.
高致病性禽流感（HPAI）病毒 H5 和 H7 亚型以及低致病性禽流感（LPAI）病毒 H5、H7 和 H9 亚型在禽类中的持续传播以及随后在人类中的感染构成了持续的大流行威胁。有人提出，由于家禽工人反复接触鸡或家养水禽，因此他们接触高致病性或低致病性禽流感病毒并随后感染的风险更高。本研究旨在检测中国北京与鸭有关的工人中针对 H5、H7 和 H9 病毒的抗体血清阳性率以及与血清阳性相关的危险因素。2011 年 3 月，从（1）商业鸭养殖场；（2）私人鸭养殖场；和（3）鸭屠宰场招募了 1741 名参与者。还招募了在后院养鸭的当地村民。通过面对面访谈进行了调查，并从受试者中采集血液样本，以检测针对 H5、H7 和 H9 病毒的抗体。我们发现，没有一个受试者对 H5 或 H7 病毒呈血清阳性，只有 0.7%（12/1741）对 H9 有抗体。不同类别的工人之间 H9 抗体血清阳性率存在统计学上的显著差异（P=0.005），村民的比例最高（1.7%）。与 H9 病毒血清阳性相关的独立危险因素包括工作场所消毒频率较低（OR，5.13[95%CI，1.07-24.58]；P=0.041；每月消毒≤2 次与>2 次）和手上有伤口时处理鸭子（OR，4.13[95%CI，1.26-13.57]；P=0.019）。虽然在中国北京与鸭有关的工人中感染 H5、H7 和 H9 病毒的风险似乎较低，但仍需要对 H9 病毒的感染进行持续监测，特别是对后院养鸭的村民进行监测，以监测任何变化。
