Eastwood Gillian, Goodman Simon J, Hilgert Nancy, Cruz Marilyn, Kramer Laura D, Cunningham Andrew A
Institute of Zoology, Zoological Society of London, London, NW1 4RY, UK,
Ecohealth. 2014;11(1):53-62. doi: 10.1007/s10393-014-0911-5. Epub 2014 May 6.
Infectious disease emergence represents a global threat to human, agricultural animal and wildlife health. West Nile virus (WNV) first emerged in the Americas in 1999 following its introduction to New York from the Old World. This flavivirus rapidly spread across much of North America, causing human, equine and avian mortalities and population declines of multiple wild bird species. It has now spread to Central and South America, and there is concern that the virus will reach the Galápagos Islands, a UNESCO World Heritage Site famous for its unique biodiversity, with potentially catastrophic results. Here, we use wild bird surveillance to examine the current WNV status in the Galapagos Islands and around the Ecuadorian city of Guayaquil (the main air and sea port serving Galápagos). We conducted serosurveys of wild birds on three Galápagos Islands (Baltra, San Cristobal and Santa Cruz) with direct transport links to the South American continent. In addition, dead birds killed by car collisions on Santa Cruz were tested for WNV infection. On mainland Ecuador, serosurveys of wild birds were conducted at three sites around Guayaquil. No evidence of WNV seropositivity or infection was detected. Although wider testing is recommended on the mainland, the study highlights a limit of WNV spread within South America. Our results indicate the continued absence of WNV on Galápagos and suggest the current likelihood of human-mediated transport of WNV to Galápagos to be low. The risk of emergence will almost certainly increase over time, however, and stringent biosecurity and surveillance measures should be put in place to minimise the risk of the introduction of WNV (and other alien pathogens) to Galápagos.
传染病的出现对人类、农业动物和野生动物的健康构成了全球性威胁。西尼罗河病毒（WNV）于1999年首次在美洲出现，它是从旧世界传入纽约的。这种黄病毒迅速蔓延至北美大部分地区，导致人类、马和鸟类死亡，并造成多种野生鸟类种群数量下降。如今它已传播到中美洲和南美洲，人们担心该病毒会抵达加拉帕戈斯群岛，这个以独特生物多样性而闻名的联合国教科文组织世界遗产地，可能会带来灾难性后果。在此，我们利用野生鸟类监测来研究加拉帕戈斯群岛以及厄瓜多尔瓜亚基尔市（加拉帕戈斯的主要航空和海港）周边地区的西尼罗河病毒现状。我们对加拉帕戈斯群岛上与南美大陆有直接交通联系的三个岛屿（巴尔特拉岛、圣克里斯托瓦尔岛和圣克鲁斯岛）的野生鸟类进行了血清学调查。此外，还对在圣克鲁斯岛因车祸死亡的鸟类进行了西尼罗河病毒感染检测。在厄瓜多尔大陆，我们在瓜亚基尔周边的三个地点对野生鸟类进行了血清学调查。未检测到西尼罗河病毒血清阳性或感染的证据。尽管建议在大陆进行更广泛的检测，但该研究凸显了西尼罗河病毒在南美洲传播的局限性。我们的结果表明加拉帕戈斯群岛目前仍未出现西尼罗河病毒，并表明目前人类将西尼罗河病毒传播到加拉帕戈斯群岛的可能性较低。然而，随着时间的推移，病毒出现的风险几乎肯定会增加，因此应实施严格的生物安全和监测措施，以尽量降低西尼罗河病毒（以及其他外来病原体）传入加拉帕戈斯群岛的风险。
