阅读理解

     The influenza virus(流感病毒) or the flu is spread from person to person in the air when an infected

person coughs or sneezes.There are 3 types of the flu:

     -Type A viruses can infect people,birds,pigs,horses,seals,whales,and other animals,such as avian flu

or bird flu.

     -Type B viruses infect people and result in smaller outbreaks(爆发). People infected with type B

viruses are often hospitalized with higher death rates.

     -Type C viruses cause mild illness in humans without the onset of an epidemic (流行病).

Most people are familiar with the symptoms of the flu,but they can be mistaken for a severe cold.The flu

infection is far more serious and can cause severe health complications (并发症). There are many viral

infections that can cause flulike symptoms.It is better to visit your doctor so other possibilities can be

ruled out before your obtaining treatment.

     The flu virus attacks the body's cells and changes into different forms,which is why people who have

received the flu shot (流感疫苗接种) may still get ill with the flu.The influenza virus is transmitted_

through direct contact with infected persons such as by inhaling (吸入)droplets when they have coughed

or sneezed.It can also be spread by handling objects such as doorknobs and telephone receivers that an

infected person has been in contact with.

     If you have the flu,get plenty of bed rest and drink lots of fluids.Most people recover from the flu in

one to two weeks.Doctors often recommend flu vaccines( 疫苗) for highrisk groups such as young

children,the elderly,those with chronic(慢性的) diseases,weak immune systems,or professionals working with highrisk groups.