Beware of "human flesh-eating bacteria" when playing in the water at the beach!

Recently, a kind of "human flesh-eating bacteria" is wreaking havoc on the beaches of Florida, USA. In July this year, flesh-eating bacteria killed three people in Florida, USA, and another 10 people were treated for infection. The mortality rate of this "flesh-eating bacteria" is over 30%. In 2012, a 69-year-old man in Ningbo, Zhejiang, my country was infected with the same flesh-eating bacteria. Doctors say that it is not difficult to treat bacterial infections caused by cannibalism, but if treatment is delayed, it will cause serious consequences such as amputation or death to the patient. therefore Friends who go to the beach to play in the water, please be careful!

What exactly is this scary-looking bacterium?

In fact, the protagonist of the story is not a new pathogen, but a bacterium that has long been known to people, namely Vibrio vulnificus . If anyone is familiar with pathogenic microorganisms, they can see at a glance that it is a microorganism of the same genus as the well-known Vibrio cholerae.

Vibrio vulnificus has another name, called marine Vibrio. This is because it lives in saline waters, and tropical and subtropical oceans and estuaries are areas where it often appears. However, strictly speaking, the name Vibrio vulnificus includes many types of bacteria that are harmful or harmless to the human body, and Vibrio vulnificus is only one of them that is harmful to humans. Vibrio vulnificus is a Gram-negative, facultative anaerobe, meaning it can live in an environment lacking oxygen. At the same time, Vibrio vulnificus also prefers an environment rich in organic matter. Therefore, in nature, in addition to being distributed in seawater, Vibrio vulnificus also appears in marine animals, especially mollusks such as oysters. Vibrio vulnificus is also one of the important microorganisms that cause disease in marine animals.

Why is Vibrio vulnificus called the "flesh-eating bacteria"?

This is because its halophilic, facultative anaerobic characteristics and rapid reproduction in the presence of organic matter make it easy for it to reproduce in human tissues. Human infection with Vibrio vulnificus occurs primarily through two pathways.

One is eating marine animals infected with Vibrio vulnificus. Usually this route is due to eating raw or undercooked fish, shrimp, oysters and other seafood, which causes Vibrio vulnificus to invade the human body through the digestive tract. This infection usually causes symptoms such as necrotic ulcers and primary sepsis, and the mortality rate can be as high as 50%.

Another pathway is that the wound is exposed to seawater containing Vibrio vulnificus, allowing Vibrio vulnificus to invade the wound and cause infection. Vibrio vulnificus infection develops very rapidly and can quickly cause blisters, skin tissue necrosis, cellulitis and even gangrene, and can eventually lead to sepsis and be fatal. The mortality rate through wound infection is about 24%. Because the infected tissue will undergo necrosis and gangrene, the bacteria has earned the notoriety of being "flesh-eating bacteria."

From an epidemiological perspective, Vibrio vulnificus infection and mortality are relatively rare compared with other microbial infections. For example, data from the U.S. Centers for Disease Control and Prevention show that from 1988 to 2007, more than 900 people in the United States reported being infected with Vibrio vulnificus. In Taiwan, approximately 100 cases of infection were reported between 2003 and 2010. Although it may be underestimated, this is not a very high number, and using the word "rampant" is a bit of an exaggeration. However, its high mortality rate after infection still reminds us that we should pay attention to this bacterial infection.

How can we prevent infection by Vibrio vulnificus?

First of all, eating raw shellfish should be strictly prohibited. Because shellfish are considered to be animals with a higher chance of being infected with Vibrio vulnificus. It should be fully heated before eating. The generally recommended heating standard is to boil it for 5 minutes after the water boils until the shell opens. If steaming it, wait until the shell opens and then steam it for 9 minutes. In addition, shellfish with shells that have not opened after cooking should not be eaten.

Secondly, the wound should be adequately protected and not exposed directly to sea water. Avoid swallowing seawater when swimming in tropical or subtropical waters, and rinse your body with clean water as soon as possible after swimming. When catching shrimp, crabs and shellfish, personal protective measures should be taken to avoid being stabbed or scratched by sharp thorns or edges, which may cause infection.

Third, some specific groups of people are more susceptible to infection with Vibrio vulnificus, so these people should pay special attention when eating seafood and visiting the beach. People with diabetes, renal dysfunction, and immune system damage, especially chronic hepatitis and cirrhosis, are at high risk of Vibrio vulnificus infection. Their probability of infection with Vibrio vulnificus can be as high as 80 times that of healthy people. Therefore, these people should pay special attention to diet and wound protection.

Fourth, early warning should be fully strengthened and treatment should not be delayed. After contact with a possible pathogen, if you find signs of suspected infection, you should seek medical attention immediately and use antibiotics for treatment. Timely treatment before the infection develops can usually achieve good results. When the condition worsens, resection or even amputation should be taken if necessary to prevent the further spread of the bacteria and cause serious diseases such as sepsis.

Medical authorities say such bacterial infections are not difficult to treat, but if treatment is delayed they can lead to amputation and other serious consequences. Therefore, after swimming in Florida, you need to rinse your entire body as quickly as possible. Nearly 100 people are infected with the bacteria every year in the area, and about one-third of them die.