Type keyword s to search. Today's Top Stories. Ab Exercises for a Stronger Core. Simon Getty Images. Why do hornets sting people, anyway? Related Stories. This content is created and maintained by a third party, and imported onto this page to help users provide their email addresses. You may be able to find more information about this and similar content at piano.
Advertisement - Continue Reading Below. More From Health. Created for From Prevention for Created by Prevention for. In a paper co-authored by Schmidt, Yamane, and others, the researchers took venom from various species of giant hornet and injected it into lab mice, a standard experiment at the time for testing a substance's toxicology.
Researchers determine toxicity using a measure called the LD Also known as the median lethal dose, it's the quantity necessary to kill 50 percent of test subjects, usually small animals like mice. In their s research, the scientists found that giant hornet venom has an LD50 of 4. The less venom required for a lethal dose, the more dangerous the substance. Giant hornets can sting repeatedly, and are capable of delivering about 10 times more venom.
The scientists determined that the venom in one giant hornet would be capable of killing about 10 mice—and that a small colony could kill a pound animal. What makes the sting of the Asian giant hornet so painful? Schmidt says that acetylcholine and histamine within the venom cause pain and swelling, assisted by chemicals called kinins that dilate blood vessels. A substance called mastoparan, not found in bee venom, and phospholipase synergistically act to degrade immune cells and spur widespread inflammation.
In combination with kinins, these chemicals can break down blood and muscle cells, Schmidt says. This destruction leads to the release of large molecules like hemoglobin, which the kidney must filter out. But several of the chemicals within the venom are toxic to the kidneys as well—one reason why giant hornet attacks can lead to renal failure, Schmidt says. The species also has a unique neurotoxin that can block nerve impulses. For the venom to reach life-threatening levels, a person likely would have to be stung by a couple hundred giant hornets, Schmidt says, compared with about a thousand honeybees.
In Japan, giant hornets cause between 30 to 50 deaths per year , but most of the fatalities are due to allergic anaphylactic reactions rather than acute toxicity, Schmidt says. Schmidt observes that giant hornets do give a warning before they sting: They fly back and forth snapping their mandibles. Schmidt himself has never been stung by an Asian giant hornet, even though he began working with them in That worked—though Schmidt does sometimes regret it.
All rights reserved. How does it feel to be stung by an Asian giant hornet, Vespa mandarinia? However, in a person who is allergic to such stings, one sting can cause death due to an anaphylactic reaction Anaphylactic Reactions Anaphylactic reactions are sudden, widespread, potentially severe and life-threatening allergic reactions. Anaphylactic reactions often begin with a feeling of uneasiness, followed by tingling In the United States, 3 or 4 times more people die from bee stings than from snakebites Snakebites Venomous snakes in the United States include pit vipers rattlesnakes, copperheads, and cottonmouths and coral snakes.
Severe envenomation can cause damage to the bitten extremity, bleeding A more aggressive type of honeybee, called the Africanized honeybee killer bee , has reached the southern and some southwestern states from South America.
By attacking their victim in swarms, these bees cause a more severe reaction than do other bees. In some people, the area swells to a diameter of 2 inches 5 centimeters or more over the next 2 or 3 days. This swelling is sometimes mistaken for infection, which is unusual after bee stings. Allergic reactions may cause rash, itching all over, wheezing, trouble breathing, and shock.
The fire ant sting usually causes immediate pain and a red, swollen area, which disappears within 45 minutes. A blister then forms, rupturing in 2 to 3 days, and the area often becomes infected. In some cases, a red, swollen, itchy patch develops instead of a blister. Isolated nerves may become inflamed, and seizures may occur in people who have had a very large number of stings.
A bee may leave its stinger in the skin. The stinger should be removed as quickly as possible by scraping with a thin dull edge for example, the edge of a credit card or a thin table knife.
An ice cube wrapped in plastic and a thin cloth and placed over the sting reduces the pain, along with nonsteroidal anti-inflammatory drugs NSAIDs and antihistamines taken by mouth. A cream or ointment containing an antihistamine, an anesthetic, a corticosteroid, or a combination of them is often useful.
Severe allergic reactions are treated in the hospital with epinephrine , intravenous fluids, and other drugs.
0コメント