VOA慢速英语 200707110041

（单词翻译）

This is the VOA Special English Health Report.

An allergy¹ is an unusually strong reaction to a substance. Many things can cause allergies². The most common cause is pollen³. Trees usually produce pollen in the spring, grasses in the summer and weeds in the fall as part of their reproductive process.


Seasonal⁴ allergies are the most common kind

Other causes include organisms such as dust mites⁵ and molds. Chemicals, plants and dead skin particles from dogs and cats can also cause allergic⁶ reactions. So can insect stings and some foods.

The most common kind of allergic reaction is itchy, watery⁷ eyes and a blocked or watery nose. Allergies can also cause red, itchy skin. Some reactions can be life-threatening -- for example, when breathing passages become blocked.

Avoiding whatever causes an allergy may not always be easy. Antihistamine⁸ drugs may offer an effective treatment. Another treatment used in some cases is called immunotherapy. A patient is injected with small amounts of the allergy-causing substance. The idea is that larger and larger amounts are given over time until the patient develops a resistance to the allergen.

In the United States, experts estimate that up to four percent of adults and up to eight percent of young children have food allergies. Every year these allergies cause about thirty thousand cases of anaphylaxis, a severe reaction that requires immediate⁹ treatment.

It can result in trouble breathing and in some cases death. The National Institute of Allergy and Infectious Diseases says one hundred to two hundred people die. It says most of the reactions are caused by peanuts and tree nuts such as walnuts¹⁰.

People can also be allergic to medicines. The American Academy of Allergy, Asthma¹¹ and Immunology says about five to ten percent of bad reactions to commonly used medicines are allergic. In other words, a person's immune system overreacts and produces an allergic reaction. The most common reactions include skin rashes, itching¹², breathing problems and swelling¹³ in areas such as the face.

But the academy estimates that allergic reactions to drugs cause one hundred six thousand deaths each year in the United States alone. It says antibiotics¹⁴ such as penicillin¹⁵ are among the drugs more likely than others to produce allergic reactions. So are anticonvulsants and hormones¹⁶ such as insulin. Other kinds include some anesthesia medicines, vaccines¹⁷ and biotechnology-produced proteins.

And that's the VOA Special English Health Report, written by Mario Ritter and Caty Weaver¹⁸. I'm Steve Ember.