Just in time for summer: an aggressive invader with a potentially deadly sting.

By Claire Gillespie
Updated May 11, 2020

If you thought COVID-19 was all you had to worry about right now, there’s a new enemy emerging from hibernation, and this one has wings: murder hornets. 

Known scientifically as the Asian giant hornet (Vespa mandarinia), murder hornets were first discovered in the US in December 2019, after the Washington State Department of Agriculture (WSDA) received and verified four reports of the insect near the cities of Blaine and Bellingham. Canada also discovered murder hornets in two locations in British Columbia in fall 2019. 

Experts are still trying to figure out if the hornets are all from the same hive. But entomologist Chris Looney of the Washington State Department of Agriculture tells Health that preliminary analysis conducted by researchers in Japan and Washington State suggested that the US specimens were more closely related to hornet populations in Korea, and the Canadian specimens to populations in Japan. 

If you’re wondering how an Asian giant hornet ended up on US or Canadian soil, nobody knows for sure. But Looney believes the most likely pathway is a stowaway in international cargo. 

“The queens overwinter by themselves in little soil shelters, and potentially other protected nooks they can find,” he says. “If a fertile queen overwintered in something that was shipped to North America, she just might find herself in a great position to wake up and start a nest in the new world.” 

To be honest, the term “insect” doesn’t really do murder hornets justice. “The Asian giant hornet is the largest hornet in the world,” WSDA spokesperson Karla Salp tells Health. “Workers are approximately 1.5 inches long and queens can be about 2 inches long, and one of the most distinctive characteristics is its large orange head.” 

“It’s a shockingly large hornet,” Todd Murray, Washington State University Extension entomologist and invasive species specialist, said in a statement. “It’s a health hazard, and more importantly, a significant predator of honeybees.”

The Asian giant hornet's graphic nickname isn't an accident. These hornets kill up to 50 people per year in Japan, and in one 2013 deluge of murder hornets in China, 42 people died and more than 1,600 were injured, reported CNN

In a video posted to his YouTube channel in November 2018, wildlife expert and self-declared “King of Sting” Coyote Peterson lets an Asian giant hornet sting him, and he described the pain as “momentous” and “excruciating.” Peterson was stung on the inside of his lower arm, and within 12 hours the swelling was all the way from his wrist to his elbow. 

It’s definitely not a good idea to let one of these huge hornets sting you. Luckily, the likelihood of encountering a murder hornet is slim. “It’s extremely unlikely to spot one outside of Washington State,” says Salp. “We have received several reports from people in the Eastern United States reporting what they think is Asian giant hornet, but it is really the European hornet, which is widespread in the area.” 

Right now, experts are taking steps to contain the murder hornets in Washington State by setting traps to capture queens and workers. Once captured, they can attach radio-transmitting collars to them to trace them back to their nests, which will be destroyed.

In the meantime, if you do happen to come across one, the WSDA advises you to “slowly and calmly leave the area.” While these insects don’t generally bother humans, they will attack if they feel threatened. Your instinct may be to swat it the way you would a regular hornet, but this is no regular hornet, and swatting may cause it to sting. If you encounter several hornets, run away from them, and if one flies inside your vehicle, stop the car slowly and open all the windows. 

Once you’ve put a safe distance between yourself and the hornet, contact your state department of agriculture. “Your local department of agriculture will also be best able to identify any local wasps that look similar,” says Looney. 

If you do get stung, Looney and Salp suggest following the official recommendations from the Washington State Department of Health. First, wash the sting site thoroughly with soap and water. Next, apply ice to slow the spread of venom and reduce pain and swelling. Like other hornets and wasps, murder hornets don’t leave a stinger behind unless it breaks off due to swatting. If you do notice a stinger embedded in your skin, use tweezers to carefully remove it.  

If you are stung multiple times or have signs of an allergic reaction, such as trouble breathing, wheezing, swelling anywhere on the face or in the mouth, difficulty swallowing, and/or dizziness, seek medical attention. Otherwise, you can take an antihistamine or apply creams to reduce itching.

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