美國疾病控制與預(yù)防中心（CDC）發(fā)布警告稱，一種名為亞洲長角蜱蟲的外來物種正在美國東部多個州擴(kuò)散，這種蜱蟲不僅繁殖速度快，還以傳播致命人類疾病著稱。

CDC的副主任本·比爾德說：“還不知道本次發(fā)現(xiàn)的蜱蟲及其擴(kuò)散對整體公共健康和農(nóng)業(yè)有何影響。在世界其他地區(qū)，亞洲長角蜱蟲能傳播多種在美國很常見的病菌。這種可以在人畜和環(huán)境中肆虐的蜱蟲目前正在美國擴(kuò)散開來，這讓我們感到擔(dān)心?！?/p>

2017年8月，美國人在新澤西州的一只綿羊身上首次發(fā)現(xiàn)亞洲長角蜱蟲，隨后擴(kuò)散至弗吉尼亞、西弗吉尼亞和紐約等八個州。這種蟲子最常出現(xiàn)在家畜身上，特別是狗和奶牛，鹿和郊狼等野生動物身上也會有。此外，已在兩名美國人身上發(fā)現(xiàn)了這種蜱蟲。

雖然CDC尚未在美國出現(xiàn)的蜱蟲身上找到有害微生物，但人們已經(jīng)知道，亞洲長角蜱蟲會通過叮咬傳播出血熱等致命疾病。這種蜱蟲的原生地是中國、韓國和日本等東亞國家，現(xiàn)已擴(kuò)展到了澳大利亞和新西蘭——由于其吸血量大，兩國奶牛的產(chǎn)奶量會因此下降25%。

亞洲長角蜱蟲能迅速擴(kuò)散的原因是雌性蜱蟲可以無性繁殖，從而找到大量宿主。人們一次有可能發(fā)現(xiàn)數(shù)千只亞洲長角蜱蟲，甚至是在一個宿主身上。

CDC表示，他們正協(xié)同美國獸醫(yī)、農(nóng)業(yè)和公共健康專家評估這種新蜱蟲的威脅。CDC稱：“畜牧業(yè)者和寵物主人應(yīng)和他們的獸醫(yī)一起定期預(yù)防蜱蟲，發(fā)現(xiàn)任何未知種類的蜱蟲要向當(dāng)?shù)剞r(nóng)業(yè)部門報告?！保ㄘ敻恢形木W(wǎng)）

譯者：Charlie

審校：夏林

The Centers for Disease Control is warning of an invasive tick species that is spreading in a number of eastern U.S. states. The tick, known as the Asian longhorned tick, can not only multiply quickly, but is known to transmit deadly diseases to humans.

“The full public health and agricultural impact of this tick discovery and spread is unknown,” Ben Beard, a deputy director at the CDC, said in a statement. “In other parts of the world, the Asian longhorned tick can transmit many types of pathogens common in the United States. We are concerned that this tick, which can cause massive infestations on animals, on people, and in the environment, is spreading in the United States.”

The Asian longhorned tick was first discovered on a sheep in New Jersey in August 2017. Since then, it has spread to Virginia, West Virginia, New York, and five other states. The tick has most often been found on domestic animals, especially dogs and cows, as well as wildlife such as deer and coyotes. But two humans have been found to be hosting it as well.

Although the CDC has found no harmful germs in ticks collected in the U.S., bites from the Asian longhorned tick have been known to transmit deadly diseases such as human hemorrhagic fever. The tick, native to East Asian countries like China, Korea and Japan, has also spread to Australia and New Zealand, where they have been known to suck so much blood from cows that milk production can fall by 25%.

The Asian longhorned tick can spread quickly because a single female tick is capable of reproducing without mating, which can result in massive host infestations. Thousands of ticks can be found at the same time, even on a single host.

The CDC said that it’s working with veterinary, agriculture and public health experts in the U.S. to assess the threat posed by the new ticks. “Livestock producers and pet owners should work with their veterinarians to maintain regular tick prevention and report any unknown tick species to their local department of agriculture,” the CDC said.