Vaccine May Have Spread Polio in US, Israel and Britain

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Vaccine¹ May Have Spread Polio in US, Israel and Britain

World health officials have nearly caused the dangerous polio virus to totally disappear by using a vaccine given by mouth rather than by injection.

However, that same kind of vaccine is now linked to polio outbreaks in the United States, Britain and Israel.

Researchers studied samples of the virus found in New York, London and Jerusalem and found that it was directly connected to the vaccine.

It is the first time in several years that polio virus connected to vaccines² has been found in wealthy countries.

History of the vaccine

For over 30 years, two drops of a liquid with a very small amount of the live polio virus triggered³ an immune⁴ response that protected billions of people. It likely saved many people from a difficult life. But it came with a small risk of spreading the disease if other people stopped getting vaccinated⁵.

Polio can cause paralysis⁶: the inability to use one's arms or legs. In some cases, it can also cause death. Former U.S. President Franklin D. Roosevelt got infected with polio in 1921 when he was 39. He used leg supports to stand from that time on.

The first polio vaccines were developed in the early 1950s and an oral vaccine has been used since the 1960s. The current oral vaccine has been used since 1988.

In recent years, polio has almost totally disappeared from wealthy nations. It is only found in a small number of poor countries in places where it is hard to find clean water.

Huge success

When the oral vaccine started to be sent around the world in 1988, there were 350,000 cases of polio each year. So far, in 2022, there were 19 cases of "wild polio," meaning polio not spread by a vaccine. The cases were in Pakistan, Afghanistan and Mozambique.

Aidan O'Leary leads the World Health Organization's polio department. O'Leary said the WHO had been centering its efforts on Afghanistan and Pakistan. He called the discovery of polio spreading in New York and London "a major surprise."

Dr. Paul Offit runs the Vaccine Education Center at Children's Hospital of Philadelphia. He praised the oral vaccine but said it may be time to end its use.

"We probably never could have gotten on top of polio in the developing world, but this is the price we are now paying," he said.

Concerns always present

Many health experts say they were aware that using a live virus vaccine could someday cause the disease to spread. Because of that worry, countries such as the Netherlands and Norway never used the oral vaccine. Instead, they only used shots with killed virus.

The live virus vaccine sometimes changes into a form that can spread and cause paralysis. It happens because recently vaccinated people can spread the live virus in their waste. Sometimes the virus spreads further.

O'Leary said he believes the U.S., Britain and Israel will work quickly to stop the virus spread. In London, young children are now being offered an additional, or booster, shot.

In New York, health officials said they do not think the virus will continue spreading because so many people are vaccinated.

Health officials have documented cases of the virus spread by the vaccine in past years. In 2020, there were over 1,000 cases spread among a large number of countries. This year, only about 200 have been found.

More and different vaccination⁷ may be needed

Experts say more vaccination is necessary even in developed countries in order to stop the spread, but they are worried that people are less trusting of vaccines today than in the past.

Scott Barrett is a professor at Columbia University in New York City who studies polio. He said vaccine pushes may be difficult today because of what he called "a reduction of trust of authorities and the political polarization in countries like the U.S. and U.K." U.K. is short for the United Kingdom or Britain.

One expert is concerned that health leaders are saying the current outbreaks are connected to the vaccine. Oyewale Tomori is a virus expert in Nigeria who worked on the African nation's effort to eliminate polio. He said it might have been better to use a different vaccine but "nobody knew it would turn out like this."

He called the situation complex and noted⁸ that "all we can do is explain how the vaccine works and hope that people understand immunization is their best protection."

Words in This Story

trigger–v. to cause something to start happening

immune –adj. able to not be affected⁹ by a disease

authorities –n. (pl.) people who have power to make decisions and enforce laws

polarization –n. to cause people to separate into opposing groups

1 vaccine   

n.牛痘苗，疫苗；adj.牛痘的，疫苗的

参考例句：

• The polio vaccine has saved millions of lives.脊髓灰质炎疫苗挽救了数以百万计的生命。
• She takes a vaccine against influenza every fall.她每年秋季接种流感疫苗。

2 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。

3 triggered   

触发的

参考例句：

• An indiscreet remark triggered off a long and costly strike. 一次轻率的讲话导致长时间、代价高昂的罢工。
• The incident triggered an armed clash. 这起事件触发了一场武装冲突。

4 immune   

adj.免疫的，有免疫力的，不受影响的，免除的

参考例句：

• I am immune from the disease,for I had it once.我对这病有免疫力，因为我已得过一次了。
• Be immune from corruption.拒腐蚀，永不沾。

5 vaccinated   

[医]已接种的，种痘的，接种过疫菌的

参考例句：

• I was vaccinated against tetanus. 我接种了破伤风疫苗。
• Were you vaccinated against smallpox as a child? 你小时候打过天花疫苗吗？

6 paralysis   

n.麻痹(症)；瘫痪(症)

参考例句：

• The paralysis affects his right leg and he can only walk with difficulty.他右腿瘫痪步履维艰。
• The paralysis affects his right leg and he can only walk with difficulty.他右腿瘫痪步履维艰。

7 vaccination   

n.接种疫苗，种痘

参考例句：

• Vaccination is a preventive against smallpox.种痘是预防天花的方法。
• Doctors suggest getting a tetanus vaccination every ten years.医生建议每十年注射一次破伤风疫苗。

8 noted   

adj.著名的，知名的

参考例句：

• The local hotel is noted for its good table.当地的那家酒店以餐食精美而著称。
• Jim is noted for arriving late for work.吉姆上班迟到出了名。

9 affected   

adj.不自然的，假装的

参考例句：

• She showed an affected interest in our subject.她假装对我们的课题感到兴趣。
• His manners are affected.他的态度不自然。