VOA健康报道2024--How Serious Is Bird Flu Outbreak?

California officials have declared a state of emergency over the spread of bird flu. It is affecting milk cows in that state and causing illnesses in some people in other U.S. states.

The avian influenza¹ virus, or bird flu, has spread among wild birds, farm birds and many mammal species².

The virus is known as Type A H5N1. It was identified for the first time in U.S. milk cows in March. Since then, bird flu has been found in about one third of U.S. states.

The U.S. Centers for Disease Control and Prevention (CDC) is following the number of cases and is reporting the latest details on its website. Most of the illnesses have been mild. Health officials said that one person in Louisiana was hospitalized with the nation's first known severe illness caused by the virus.

California Governor Gavin Newsom said he declared the state of emergency so state workers could take faster action.

California officials have been testing milk tanks. They said they have found the virus in hundreds of herds⁴. The virus was recently found in Southern California dairy farms. It was found in the state's Central Valley in August.

What is the risk to the general public?

Officials with the CDC repeated that the public has a low risk of getting the virus. There are no reports of person-to-person infection and no signs that the virus has changed to spread easily among humans.

Flu experts say it is too soon to know how the situation will change. But some experts are worried because flu viruses are mutating all the time and small genetic⁵ changes could take place.

Are cases becoming more serious?

Health officials said the first known case of severe illness in the U.S. was found in a patient in Louisiana. The person is older than 65 and has other medical problems. Officials said the person showed severe breathing problems after being near a group of sick birds. The CDC said that the Louisiana case is the first confirmed U.S. infection connected with backyard birds, or birds kept near a home.

Almost all the earlier infections in the U.S. have been in farmworkers dealing⁶ with infected dairy cattle or birds. In two cases - an adult in Missouri and a child in California - health officials have not learned how they became infected.

Angela Rasmussen is a virus expert at the University of Saskatchewan in Canada. She said as more people become infected, more severe illnesses will be reported. Rasmussen said, "I assume that every H5N1 virus has the potential to be very severe and deadly."

The World Health Organization says on its website that from 2003 to November 2024 about 142 people died from the H5N1 virus around the world. Most of the deaths were in Southeast Asia.

How can people protect themselves?

People who have contact with dairy cows, commercial poultry⁷ or with backyard birds are at higher risk than other people. CDC and other experts said those people should use breathing, eye, and hand protection, especially if the animals appear ill or if they die.

The CDC said in July that it would buy $5 million in vaccines⁸ for farmworkers to protect against seasonal⁹ flu. If someone becomes infected with two flu types at the same time, it might permit the bird flu virus to mutate and to become more dangerous.

How else is bird flu spread?

The H5N1 virus can also be spread in raw, or unpasteurized, milk. The U.S. Food and Drug Administration says pasteurized milk is safe to drink because the heat treatment kills the virus.

But high levels of the virus have been found in unpasteurized milk. Health officials urge people to avoid drinking raw milk. It can spread other germs in addition to bird flu.

The U.S. Agriculture Department has increased its testing of raw milk across the country to identify and contain avian flu. Federal officials ordered milk testing which began this month in 13 states.

I'm Anna Matteo.

Jonel Aleccia reported this story for the Associated Press. Jill Robbins adapted it for Learning English.

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Words in This Story

mild -adj. having little effect on a person, not severe at all

herd³ -n. a group of animals such as cattle or sheep

dairy - adj. of or relating to a type of farming that deals with the production of milk and foods made from milk

mutate - v. to cause (a gene) to change and create an unusual characteristic in a plant or animal

backyard - n. the general area near and around someone's home

assume -v. to take something as correct without confirming that it is correct or right

potential - n. a chance or possibility that something will happen or exist in the future

poultry - n. birds (such as chickens and ducks) that are raised on farms for their eggs or meat

pasteurized - adj. put through a process in which a liquid (such as milk or cream) is heated to a temperature that kills harmful germs and then cooled quickly

1 influenza   

n.流行性感冒，流感

参考例句：

• They took steps to prevent the spread of influenza.他们采取措施
• Influenza is an infectious disease.流感是一种传染病。

2 species   

n.物种，种群

参考例句：

• Are we the only thinking species in the whole of creation?我们是万物中惟一有思想的物种吗？
• This species of bird now exists only in Africa.这种鸟现在只存在于非洲。

3 herd   

n.兽群，牧群；vt.使集中，把…赶在一起

参考例句：

• She drove the herd of cattle through the wilderness.她赶着牛群穿过荒野。
• He had no opinions of his own but simply follow the herd.他从无主见，只是人云亦云。

4 herds   

兽群( herd的名词复数 )； 牧群； 人群； 群众

参考例句：

• Regularly at daybreak they drive their herds to the pasture. 每天天一亮他们就把牲畜赶到草场上去。
• There we saw herds of cows grazing on the pasture. 我们在那里看到一群群的牛在草地上吃草。

5 genetic   

adj.遗传的，遗传学的

参考例句：

• It's very difficult to treat genetic diseases.遗传性疾病治疗起来很困难。
• Each daughter cell can receive a full complement of the genetic information.每个子细胞可以收到遗传信息的一个完全补偿物。

6 dealing   

n.经商方法，待人态度

参考例句：

• This store has an excellent reputation for fair dealing.该商店因买卖公道而享有极高的声誉。
• His fair dealing earned our confidence.他的诚实的行为获得我们的信任。

7 poultry   

n.家禽，禽肉

参考例句：

• There is not much poultry in the shops. 商店里禽肉不太多。
• What do you feed the poultry on? 你们用什么饲料喂养家禽?

8 vaccines   

疫苗，痘苗( vaccine的名词复数 )

参考例句：

• His team are at the forefront of scientific research into vaccines. 他的小组处于疫苗科研的最前沿。
• The vaccines were kept cool in refrigerators. 疫苗放在冰箱中冷藏。

9 seasonal   

adj.季节的，季节性的

参考例句：

• The town relies on the seasonal tourist industry for jobs.这个城镇依靠季节性旅游业提供就业机会。
• The hors d'oeuvre is seasonal vegetables.餐前小吃是应时蔬菜。