Adlhoch Cornelia, Brouwer Adam, Kuiken Thijs, Mulatti Paolo, Smietanka Krzysztof, Staubach Christoph, Willeberg Preben, Barrucci Federica, Verdonck Frank, Amato Laura, Baldinelli Francesca
EFSA J. 2018 Mar 28;16(3):e05240. doi: 10.2903/j.efsa.2018.5240. eCollection 2018 Mar.
Between 16 November 2017 and 15 February 2018, one highly pathogenic avian influenza (HPAI) A(H5N6) and five HPAI A(H5N8) outbreaks in poultry holdings, two HPAI A(H5N6) outbreaks in captive birds and 22 HPAI A(H5N6) wild bird events were reported within Europe. There is a lower incursion of HPAI A(H5N6) in poultry compared to HPAI A(H5N8). There is no evidence to date that HPAI A(H5N6) viruses circulating in Europe are associated with clades infecting humans. Clinical signs in ducks infected with HPAI A(H5N8) seemed to be decreasing, based on reports from Bulgaria. However, HPAI A(H5N8) is still present in Europe and is widespread in neighbouring areas. The majority of mortality events of wild birds from HPAIV A(H5) in this three-month period involved single birds. This indicates that the investigation of events involving single dead birds of target species is important for comprehensive passive surveillance for HPAI A(H5). Moreover, 20 low pathogenic avian influenza (LPAI) outbreaks were reported in three Member States. The risk of zoonotic transmission to the general public in Europe is considered to be very low. The first human case due to avian influenza A(H7N4) was notified in China underlining the threat that newly emerging avian influenza viruses pose for transmission to humans. Close monitoring is required of the situation in Africa and the Middle East with regards to HPAI A(H5N1) and A(H5N8). Uncontrolled spread of virus and subsequent further genetic evolution in regions geographically connected to Europe may increase uncertainty and risk for further dissemination of virus. The risk of HPAI introduction from Third countries via migratory wild birds to Europe is still considered much lower for wild birds crossing the southern borders compared to birds crossing the north-eastern borders, whereas the introduction via trade is still very to extremely unlikely.
2017年11月16日至2018年2月15日期间，欧洲境内报告了一起家禽养殖场高致病性禽流感A(H5N6)疫情、五起家禽养殖场高致病性禽流感A(H5N8)疫情、两起圈养鸟类高致病性禽流感A(H5N6)疫情以及22起高致病性禽流感A(H5N6)野鸟事件。与高致病性禽流感A(H5N8)相比，高致病性禽流感A(H5N6)在家禽中的传入情况较少。迄今为止，没有证据表明在欧洲传播的高致病性禽流感A(H5N6)病毒与感染人类的进化枝有关。根据保加利亚的报告，感染高致病性禽流感A(H5N8)的鸭的临床症状似乎在减少。然而，高致病性禽流感A(H5N8)仍在欧洲存在，并在周边地区广泛传播。在这三个月期间，大多数由高致病性禽流感病毒A(H5)导致的野鸟死亡事件涉及单只鸟类。这表明，对涉及目标物种单只死亡鸟类的事件进行调查，对于高致病性禽流感A(H5)的全面被动监测很重要。此外，三个成员国报告了20起低致病性禽流感疫情。欧洲向普通公众进行人畜共患病传播的风险被认为非常低。中国通报了首例人感染甲型H7N4禽流感病例，凸显了新出现的禽流感病毒对传播给人类构成的威胁。需要密切监测非洲和中东地区高致病性禽流感A(H5N1)和A(H5N8)的情况。在与欧洲地理相连的地区，病毒的无控制传播以及随后进一步的基因进化，可能会增加病毒进一步传播的不确定性和风险。与穿越东北边境的鸟类相比，通过迁徙野鸟从第三国将高致病性禽流感引入欧洲的风险，对于穿越南部边境的野鸟来说仍被认为要低得多，而通过贸易引入的可能性仍然非常小到极不可能。
