What's a 'Murder Hornet'?

asian giant hornet

"Murder hornet" is a misleading nickname for the world’s largest species of hornet, the Asian giant hornet. As the name suggests, they originate in Asia. But they've since been found in Washington State. Scientists first confirmed their presence near Blaine, WA, in December 2019. Sightings have continued at least through 2021.

Contrary to their nickname, these hornets aren't known to attack people or pets. The only "murders" they're likely to commit are those of the honeybees.

What Does a Murder Hornet Look Like?

It’s unusually large for a hornet -- up to 2 inches long. That's five times bigger than a honeybee.

It has a large, solid orange or yellow head with black, teardrop-shaped eyes. The middle (the thorax) is dark, and in adults it tapers in at the waist to meet the bottom section, known as the abdomen.

The abdomen is marked with alternating bands of orange or yellow with bands of black or brown.

Some other bugs look similar, but most are much smaller than the murder hornet. You can distinguish larger lookalikes like the western cicada killer and the eastern cicada killer by their smaller heads, lighter colored thoraxes, and round eyes. The bands on their abdomens also look different.

What’s the Biggest Risk From Murder Hornets?

The main risk is to the bee population that supports many of our food crops through pollination. This is especially true of “social" types of bees that live in hives and make honey.

The hornets attack in late summer and early fall when worker hornets need to provide food for developing young. They attack the beehive, kill the adult bees, leave their bodies at the bottom of the hive, and take developing bees, in the form of larvae and pupae, back to their nests for food.  

What About Stings From Murder Hornets?

Murder hornets aren't usually aggressive to humans. But they will sting to protect their nest or to keep you away from a beehive they've invaded. If that happens, their larger size can make their stings worse than those from other insects. There are several reasons for this:

  • The stinger is longer than that of other wasps.
  • A sting can deliver a lot more venom and can damage tissue.
  • It may hurt worse than other stings.

Like other wasps and hornets, Asian giant hornets can sting several times. Though it’s very rare for a group of hornets to attack a human, it’s not unheard of. And it can be serious if it does occur.

Beekeeper's clothing often can’t protect against the stings. The murder hornet's stinger is so long that it can penetrate protective garments.

People who are allergic to bee or wasp stings should be especially careful around Asian giant hornets.

What Can You Do to Protect Yourself?

You probably don’t have much to worry about. Few confirmed sightings of murder hornets have occurred in the U.S., and all have been limited to Washington State.

Still, it’s best to avoid them if you see them. If you do run into one, move away slowly and calmly. Swatting at it might lead it to sting you.

If a hornet or hornets get into your car, stop the vehicle as slowly and calmly as possible. Open all the windows, and get out of the car if you’re in a safe enough place.

To make you less likely to attract them in the first place: 

 

  • Avoid perfume and cologne as well as grooming products with lots of fragrance.
  • Cover food and drink when you’re outside. 
  • Keep your living areas clean of garbage, food, dog droppings, and fruit fallen from trees or your garden. 
  • Use “wasp guards” to keep wasps out of hummingbird feeders.  

What Should You Do If You’re Stung?

  • Wash the site thoroughly with soap and water.
  • Put ice on the sting to slow the spread of venom.
  • Get to a doctor quickly if you have multiple stings or an allergic reaction.
  • Consider an antihistamine pill or cream to reduce itching and swelling.

Call 911 if a person who has been stung has any of these:

  • Lightheadedness or dizziness
  • Trouble breathing or shortness of breath
  • Difficulty swallowing or tightness in the throat
  • A blue color to the skin
  • Swelling on the face or in the mouth
WebMD Medical Reference Reviewed by Neha Pathak, MD on June 17, 2021

Sources

Stanford University: “If murder hornets attack U.S. honey bees, wild bees may serve as critical backup pollinators, Stanford experts say.”

USDA Animal and Plant Health Inspection Service: “Asian Giant Hornet.”

Western Governors Association: “Invasive Species Data: Citizen Science Data Critical to Fighting the Asian Giant Hornet.”

Washington State Department of Agriculture: “Asian Giant Hornets And Human Health,” “Invasive Hornets.”

Clemson University: "Asian Giant Hornets."

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