Zou Shumei, Guo Junfeng, Gao Rongbao, Dong Libo, Zhou Jianfang, Zhang Ye, Dong Jie, Bo Hong, Qin Kun, Shu Yuelong
Chinese National Influenza Center, National Institute for Viral Disease Control and Prevention, 155 Changbai Road, Beijing 102206, P,R China.
Virol J. 2013 Sep 15;10:289. doi: 10.1186/1743-422X-10-289.
In the spring of 2013, a novel avian-origin influenza A (H7N9) virus in Eastern China emerged causing human infections. Concerns that a new influenza pandemic could occur were raised. The potential effect of chemical agents and physical conditions on inactivation of the novel avian influenza H7N9 virus had not been assessed.
To determine the inactivation effectiveness of the novel avian influenza A (H7N9) virus under various physical conditions and chemical treatments, two H7N9 viruses A/Anhui/1/2013 and A/Shanghai/1/2013 were treated by varied temperatures, ultraviolet light, varied pHs and different disinfectants. The viruses with 107.7 EID50 were exposed to physical conditions (temperature, ultraviolet light and pH) or treated with commercial chemical agents (Sodium Hypochlorite, Virkon®-S, and Ethanol) respectively. After these treatments, the viruses were inoculated in SPF embryonated chicken eggs, the allantoic fluid was collected after 72-96 hours culture at 35°C and tested by haemagglutination assay.
Both of the tested viruses could tolerate conditions under 56°C for 15 minutes or 60°C for 5 minutes, but their infectivity was completely lost under 56°C for 30 minutes, 65°C for 10 minutes, 70°C, 75°C and 100°C for 1 minute. It was also observed that the H7N9 viruses lost their infectivity totally after exposure of ultraviolet light irradiation for 30 minutes or longer time. Additionally, the viruses were completely inactivated at pH less than 2 for 0.5 hour or pH 3 for 24 hours, however, viruses remained infectious under pH treatment of 4-12 for 24 hours. The viruses were totally disinfected when treated with Sodium Hypochlorite, Virkon®-S and Ethanol at recommended concentrations after only 5 minutes.
The novel avian influenza A (H7N9) virus can be inactivated under some physical conditions or with chemical treatments, but they present high tolerance to moderately acidic or higher alkali conditions. The results provided the essential information for public health intervention of novel H7N9 avian influenza outbreak.
2013年春季，中国东部出现一种新型禽源甲型流感（H7N9）病毒，导致人类感染。人们担心可能会发生新的流感大流行。化学制剂和物理条件对新型H7N9禽流感病毒灭活的潜在影响尚未得到评估。
为确定新型甲型流感（H7N9）病毒在各种物理条件和化学处理下的灭活效果，将两种H7N9病毒A/安徽/1/2013和A/上海/1/2013分别置于不同温度、紫外线、不同pH值环境及用不同消毒剂进行处理。将含107.7 EID50的病毒分别暴露于物理条件（温度、紫外线和pH值）下或用市售化学制剂（次氯酸钠、卫可®-S和乙醇）进行处理。处理后，将病毒接种于SPF鸡胚，在35℃培养72 - 96小时后收集尿囊液，并用血凝试验进行检测。
两种受试病毒在56℃下可耐受15分钟或60℃下耐受5分钟，但在56℃下30分钟、65℃下10分钟、70℃、75℃和100℃下1分钟时其感染性完全丧失。还观察到，H7N9病毒在紫外线照射30分钟或更长时间后感染性完全丧失。此外，病毒在pH值小于2的环境中0.5小时或pH值为3的环境中24小时后完全灭活，然而，在pH值为4 - 12的环境中处理24小时后病毒仍具有感染性。用推荐浓度的次氯酸钠、卫可®-S和乙醇处理病毒仅5分钟后，病毒即被完全灭活。
新型甲型流感（H7N9）病毒可在某些物理条件下或通过化学处理灭活，但它们对中等酸性或较高碱性条件具有较高耐受性。这些结果为新型H7N9禽流感疫情的公共卫生干预提供了重要信息。
