Exercise 7. Form the words.

What Is Influenza?

The respiratory infection influenza, (common) known as the flu, causes symptoms that include fever, muscle aches, a sore throat, and a cough. In its early stages, influenza sometimes is confused with the common cold because both affect similar parts of the body, but the flu is more severe, lasts longer, and can cause (danger), even fatal, complications.

What are influenza types?

Influenza virus is classified as type A, B, or C. Types A and В cause large flu outbreaks or epidemics each year, whereas type С flu virus causes only mild symptoms. Type A influenza virus is the most (threaten) to humans because it is likely to mutate into new strains (frequent).

How Common Is Influenza?

Millions of people contract the flu each year. Influenza is (extreme) contagious, mostly because people often spread it before they even know that they are sick. Also, those with the infection usually remain contagious for about a week after first showing symptoms. When an infected person sneezes, coughs, or talks too (close) to others, the flu virus is transmitted through tiny drops of fluid that are launched into the air and can be inhaled by someone else. The virus can also be left on surfaces that a person with the flu has touched, such as doorknobs, desks, and keyboards, so people who forget to wash their hands after touching these objects can (easy) become infected from rubbing their eyes or touching their mouth. The virus is very (hard) and can live as long as two days on hard surfaces.

Influenza affects people of all ages, but it is a special problem for the very young, the (old), and people with weakened immune systems, (include) people with AIDS, people with certain cancers, people who have had organ transplants, etc.

How Do People Know They Have the Flu?

Flu symptoms are usually worse than those seen with a cold. Symptoms include: sneezing, (run) nose, and congestion (stuffed-up nose), high fever, headache, chills, dry-sounding cough, muscle aches, poor appetite, (tired).

Most people have symptoms of the flu for 7 to 14 days. The high fever and body aches usually (appear) within a few days, but those symptoms may be quickly replaced by a sore throat, runny nose, and lingering cough. In some cases, fever may even return for a brief period. Feelings of tiredness and (exhaust) can last several days or weeks in some people with the flu. Trying to return to a normal routine too quickly can cause symptoms, especially exhaustion, to re-occur.

People who get the flu sometimes develop complications. The flu virus (weak) the body's defenses against (infect). About two weeks after getting the flu, some people develop bronchitis or pneumonia. Influenza can also (worse) the symptoms of other common heart and lung diseases. Hundreds of thousands of Americans are (hospital) every year due to the virus, and about 20,000 die from the flu or its complications.

Can the Flu Be Prevented?

Infection by some strains of influenza can be prevented with a flu (vaccine) in the fall. The vaccine contains (active) versions of the three flu viruses—two of type A and one of type В—that (research) suspect will be most likely to cause influenza during the coming winter and early spring. Because the influenza virus is (constant) mutating, the flu shot does not guarantee that a person will not get the flu. It does, however, reduce the chance of becoming sick by 80 to 90 percent.

Because the (high) contagious flu virus is easily passed from person to person through the air and through its being left on surfaces, the virus can be almost anywhere. Experts recommend that hands be washed (thorough) with warm, (soap) water for at least 15 to 30 seconds after one has used a public restroom and before eating or touching the face.

Avoiding contact with people who have the flu can also (low) the risk of catching it. By avoiding close contact in large crowds, especially at schools or in malls, and by not touching (use) tissues or and not sharing drinks, a person can reduce the chance of becoming sick.