Not to Alarm Anyone, but Flesh-Eating Screwworms Have Entered the US
Not to Alarm Anyone, but Flesh-Eating Screwworms Have Entered the US
无意引起恐慌，但食肉螺旋蝇已进入美国
A case of New World screwworm has been confirmed in South Texas, the US Department of Agriculture announced Wednesday night. It marks the first detected breach of the US-Mexico border by the ravenous flesh-eating flies, which have been making their way up through Central America for the past several years.
美国农业部周三晚间宣布，德克萨斯州南部已确诊一例新世界螺旋蝇（New World screwworm）病例。这标志着这种贪婪的食肉蝇首次被发现突破美墨边境，过去几年里，它们一直沿着中美洲北上。
In a social media post on Wednesday afternoon, the USDA revealed that a sample from Texas had been sent to the National Veterinary Services Laboratories (NVSL) in Ames, Iowa, for confirmatory testing of a screwworm infection. Agriculture Secretary Brooke Rollins later posted that the testing had confirmed the infection, which was found in a three-week-old calf in Zavala County, Texas.
周三下午，美国农业部在社交媒体上发文称，已将一份来自德克萨斯州的样本送往位于爱荷华州埃姆斯市的国家兽医服务实验室（NVSL），以确认是否为螺旋蝇感染。农业部长布鲁克·罗林斯（Brooke Rollins）随后发文证实，感染已得到确认，该病例发现于德克萨斯州扎瓦拉县（Zavala County）的一头三周大的小牛身上。
Chatter of a screwworm detection had already been building this week, rattling the US cattle industry. Although many animals, including humans, can be victims of the parasite, the screwworm is especially dangerous to livestock. Female screwworms lay hundreds of eggs in the wounds and openings of warm-blooded creatures, allowing their larvae to feast on the living animals, causing deep, festering, life-threatening wounds.
本周关于发现螺旋蝇的传言一直在发酵，令美国养牛业感到不安。尽管包括人类在内的许多动物都可能成为这种寄生虫的受害者，但螺旋蝇对牲畜的威胁尤为严重。雌性螺旋蝇会在温血动物的伤口和孔洞中产下数百枚卵，其幼虫会以活体动物为食，造成深层、化脓且危及生命的伤口。
Although the screwworm was once endemic to the US, it was eradicated amid a yearslong control effort in the 1960s. The USDA estimates that keeping screwworms out of the US has saved the livestock industry $900 million each year.
虽然螺旋蝇曾在美国广泛存在，但在20世纪60年代经过多年的治理努力后，该物种已被根除。美国农业部估计，将螺旋蝇拒之门外每年为畜牧业节省了9亿美元。
But the fly has broken through control efforts in Central America and has been inching closer. On May 28, a case was found 25 miles from the border in a five-year-old goat in Coahuila, Mexico, according to the USDA. The case was one of many detected in recent days, including a case in a calf just 39 miles from the border, also in Coahuila.
然而，这种蝇类已经突破了中美洲的防控防线，并不断向北逼近。据美国农业部称，5月28日，在距离边境25英里处的墨西哥科阿韦拉州（Coahuila），一只五岁的山羊身上发现了病例。这是近期发现的众多病例之一，其中包括一头距离边境仅39英里、同样位于科阿韦拉州的小牛病例。
Disputed Detections
关于检测结果的争议
In a media call on Tuesday, Agriculture secretary Brooke Rollins said, “There is no doubt that this is a very, very serious threat to our livestock.” But she also disputed claims that the fly is closer or even already in the US. On Monday, state representative Don McLaughlin claimed on social media that a screwworm case was found just one mile from the Texas border, which Rollins and the USDA denied.
在周二的媒体电话会议上，农业部长布鲁克·罗林斯表示：“毫无疑问，这对我们的牲畜构成了非常、非常严重的威胁。”但她同时也反驳了关于该蝇类已更近甚至已经进入美国的说法。周一，州众议员唐·麦克劳克林（Don McLaughlin）在社交媒体上声称，在距离德州边境仅一英里处发现了螺旋蝇病例，罗林斯和美国农业部对此予以否认。
“When that false information gets out, it causes significant panic,” Rollins said Tuesday, according to the Texas Tribune. “And rightly so, especially if it’s coming from elected officials and the media.”
据《德克萨斯论坛报》报道，罗林斯周二表示：“当这种虚假信息传出时，会引起巨大的恐慌。这是理所当然的，尤其是当这些信息来自民选官员和媒体时。”
On Wednesday, Reuters reported that McLaughlin suspected the fly was now here. He said samples taken Tuesday from two calves on a ranch in La Pryor, Texas—which is in Zavala County, where the screwworm infection was confirmed—were being tested as possible screwworm infections. One infection was said to be in an umbilical cord wound of one of the calves. McLaughlin said he had seen images and videos of the animals and that the larvae seen in them looked like screwworm larvae.
周三，路透社报道称，麦克劳克林怀疑该蝇类已经进入美国。他表示，周二从德克萨斯州拉普赖尔（La Pryor）一个牧场的两头小牛身上采集的样本正在接受检测，以确认是否为螺旋蝇感染。据悉，其中一头小牛的感染部位位于脐带伤口处。麦克劳克林称他看过这些动物的图片和视频，其中的幼虫看起来很像螺旋蝇幼虫。
Reuters was shown one of the photos, which it reported as showing “multiple larvae resembling the screwworm inside a bloody circular wound on an animal” but said it “could not immediately verify the photo.” “At this point, it’s unconfirmed that it’s the New World screwworm,” McLaughlin told the outlet earlier Wednesday. “It looks like it, but it’s unconfirmed.”
路透社查看了其中一张照片，报道称照片显示“动物血淋淋的圆形伤口内有多个类似螺旋蝇的幼虫”，但表示“无法立即核实该照片”。麦克劳克林周三早些时候告诉该媒体：“目前还不能确定这就是新世界螺旋蝇。它看起来很像，但尚未得到证实。”
With the finding now confirmed, the USDA said in a press release Wednesday night that it is setting up a “unified Incident Command Team” with the Texas Animal Health Commission and sending response personnel to the area. It is also setting up a 20-kilometer (12.4-mile) zone around the detected infection for quarantine, movement restrictions, and increased surveillance and fly trapping.
随着检测结果的确认，美国农业部在周三晚间的新闻稿中表示，正与德克萨斯州动物卫生委员会组建一个“统一事件指挥小组”，并向该地区派遣应急人员。此外，他们还在感染发现地周围设立了一个20公里（12.4英里）的区域，用于隔离、限制移动，并加强监测和诱捕工作。
Screwworm Comeback
螺旋蝇的卷土重来
Screwworms were eradicated in the US in the 1960s amid a concerted effort to annihilate their population. This is done with aerial bombings of sterile male flies, which is the most effective weapon against the parasites. The mass release of dud studs elbows out fertile males, preventing them from mating with females, which generally mate only once.
20世纪60年代，美国通过协同努力消灭了螺旋蝇种群，从而将其根除。这一过程是通过空中投放不育雄蝇来实现的，这是对抗这种寄生虫最有效的武器。大量投放“不育雄蝇”会排挤掉可育雄蝇，阻止它们与雌蝇交配，而雌蝇通常一生只交配一次。
With this method, called Sterile Insect Technique, the flies were eradicated not just from the US but from all of Central America. They were declared eradicated from Panama in 2006.
通过这种被称为“昆虫不育技术”（Sterile Insect Technique）的方法，螺旋蝇不仅在美国，而且在整个中美洲都被根除。2006年，巴拿马宣布彻底消灭了该物种。
Until recently, the screwworm population was kept at bay via a biological barrier along the Darién Gap at the border of Panama and Colombia. The USDA partnered with authorities in Panama to build a sterile fly production facility at the gap to regularly release sterile flies and hold the line. But in 2022, the barrier was breached, and the flies have been relentlessly buzzing northward since.
直到最近，螺旋蝇种群一直被巴拿马和哥伦比亚边境达连地峡（Darién Gap）的一道生物屏障所阻挡。美国农业部与巴拿马当局合作，在该地峡建立了一个不育蝇生产设施，定期释放不育蝇以守住防线。但在2022年，这道屏障被突破，此后这些蝇类便不断向北蔓延。
In response, the US has expanded surveillance and trapping efforts in Texas. It is also constructing a $750 million sterile fly production facility in South Texas. The USDA says it is dispersing 100 million sterile insects per week in Mexico and along the US-Mexico border to prevent the flies from advancing further.
作为应对，美国扩大了在德克萨斯州的监测和诱捕力度。此外，美国还在德州南部建设一座耗资7.5亿美元的不育蝇生产设施。美国农业部表示，目前每周在墨西哥及美墨边境投放1亿只不育昆虫，以防止该物种进一步扩散。
In the press release Wednesday night, the USDA said it will be releasing sterile flies via ground-release chambers in the area around the detection. That’s in addition to the 4 million flies already being released in the area by air this week. “The United States has defeated this pest before, and we will do it again,” Dudley Hoskins, USDA undersecretary for marketing and regulatory programs, wrote in the press release.
在周三晚间的新闻稿中，美国农业部表示，将在发现病例的周边地区通过地面释放装置投放不育蝇。这还不包括本周已在该地区通过空中投放的400万只不育蝇。美国农业部负责营销和监管项目的副部长达德利·霍斯金斯（Dudley Hoskins）在新闻稿中写道：“美国曾经战胜过这种害虫，我们一定会再次做到。”
This story originally appeared on Ars Technica. 本文最初发表于 Ars Technica。