November 7, 2001
Contact: Jennifer Day, (313) 577-1429, jday@med.wayne.edu

Tip Sheet:  November marks the start of flu season

Nobody worries too much about the flu, but it kills an estimated 20,000 people every year, according to the U.S. Centers for Disease Control and Prevention. The CDC estimate that 35 to 50 million Americans will come down with the flu during each flu season, which typically lasts from November to March.

Influenza, or the flu, is a respiratory infection caused by a variety of related viruses. The flu differs in several ways from the common cold, a respiratory infection also caused by viruses. For example, people with colds rarely get fevers or headaches or suffer from the extreme exhaustion that flu viruses cause.

Children are two to three times more likely than adults to get sick with the flu, and children frequently spread the virus to others. Although most people recover from the illness, CDC estimates that in the United States more than 100,000 people are hospitalized annually.

Wayne State University School of Medicine experts are available to discuss the flu and the importance of getting a flu shot. Possible story ideas may include.

• How can people tell the difference between the flu and anthrax?
  Given recent biological attacks and fear relating to those incidents, many people are asking this question and wondering when they should go to the doctor for symptoms that any other year would simply warrant plenty of fluids and bed rest.
  

• Who should get a flu shot?
  Every year, people are encouraged to get flu shots to ward of many viruses that cause the flu. Find out more about the flu shot and who should definitely get a flu vaccine. Further, some are wondering whether this year will see record turnout for flu shots, given the anthrax scare. If that’s so, will there be enough to go around? Or will those who need it most be left out in the cold?
  

• What’s new in flu vaccine research?
  Chris Roberts, PhD, assistant professor of immunology and microbiology, is looking at a particular strain of flu viruses, known as “filamentous,” to produce better flu vaccines. Although filamentous viruses have unique properties that make them more infectious, those same properties may make them better agents for fighting the flu.

Flu Fact Sheet
The following information was taken from the website of the National Institute of Allergy and Infectious Diseases (www.niaid.nih.gov).

When and Where Do People Usually Get the Flu?
Flu outbreaks usually begin suddenly and occur mainly in the late fall and winter. The disease spreads through communities creating an epidemic. During the epidemic, the number of cases peaks in about three weeks and subsides after another three or four weeks. Half of the population of a community may be affected. Because schools are an excellent place for flu viruses to attack and spread, families with school-age children have more infections than other families, with an average of one-third of the family members infected each year.

Is the Flu an Important Disease?
Besides the rapid start of the outbreaks and the large numbers of people affected, the flu is an important disease because it can cause serious complications. Most people who get the flu get better within a week (although they may have a lingering cough and tire easily for a while longer). For elderly people, newborn babies, and people with certain chronic illnesses, however, the flu and its complications can be life threatening.

How is the Flu Transmitted?
You can get the flu if someone around you who has the flu coughs or sneezes. You can get the flu simply by touching a surface like a telephone or doorknob that has been contaminated by a touch from someone who has the flu. The viruses can pass through the air and can enter your body through your nose or mouth. If you've touched a contaminated surface, they can pass from your hand to your nose or mouth. You are at greatest risk of getting infected in highly populated areas, such as in crowded living conditions and in schools.

What are Flu Symptoms?
If you get infected by the flu virus, you will usually feel symptoms one to four days later. You can spread the flu to others before your symptoms start and for another three to four days after your symptoms appear. The symptoms start very quickly. They include headache, chills, dry cough, body aches, fever, stuffy nose and sore throat. Typically, the fever begins to decline on the second or third day of the illness. The flu almost never causes symptoms in the stomach and intestines. The illness that some people often call “stomach flu” is not actually influenza.

How Does a Doctor Diagnose the Flu?
Usually, doctors or other health care workers diagnose the flu on the basis of whether flu is epidemic in the community and whether the patient's complaints fit the current pattern of symptoms. Doctors rarely use laboratory tests to identify the virus during an epidemic. Health officials, however, monitor certain U.S. health clinics and do laboratory tests to determine which type of flu virus is responsible for the epidemic.

How Can I Keep from Getting the Flu?
The main way to keep from getting the flu is to get a yearly flu vaccine. You can get the vaccine at your doctor’s office or a local clinic, and in many communities at workplaces, supermarkets, and drugstores. You must get the vaccine every year because it changes.

Scientists make a different vaccine every year because the strains of flu viruses change from year to year. Nine to 10 months before the flu season begins, they prepare a new vaccine made from inactivated (killed) flu viruses. Because the viruses are killed, they cannot cause infections. The vaccine preparation is based on the strains of the flu viruses that are in circulation at the time.

Sometimes, an unpredicted new strain may appear after the vaccine has been made and distributed to doctors and clinics. Because of this, even if you do get the flu vaccine, you still may get infected. If you do get infected, however, the disease usually is milder because the vaccine still will give you some protection.

Your immune system takes time to respond to the flu vaccine. Therefore, you should get vaccinated six to eight weeks before flu season begins to prevent getting infected or reduce the severity of flu if you do get it. The vaccine itself cannot cause the flu, but you could become exposed to the virus by someone else and get infected soon after you are vaccinated.

Are there possible side effects from the flu vaccine?
You should be aware that the flu vaccine may cause side effects. The most common side effect in children and adults is soreness at the site of the vaccination. Other side effects, especially in children who previously have not been exposed to the flu virus, include fever, tiredness and sore muscles. These side effects may begin 6 to 12 hours after vaccination and may last for up to two days.

Viruses for producing the vaccine are grown in chicken eggs and then killed with a chemical so that they can no longer cause an infection. The flu vaccine may contain some egg protein, which can cause an allergic reaction. Therefore, if you are allergic to eggs or have ever had a serious allergic reaction to the flu vaccine, CDC recommends that you consult with your doctor before getting vaccinated.

Who should get the flu vaccine?
If you are in any of the following groups or live in a household with someone who is, CDC recommends that you get the flu vaccine:

• You are 50 years of age or older.
• You have chronic diseases of your heart, lungs, or kidneys.
• You have diabetes.
• Your immune system does not function properly.
• You have a severe form of anemia.
• You will be more than three months pregnant during the flu season.
• You live in a nursing home or other chronic-care housing facility.

The vaccine can be administered to children as young as six months old. Children should get the flu vaccine if they are taking long-term aspirin treatment, as they may be at risk of developing Reye's syndrome following a flu infection. They should also get the flu vaccine if they live in a household with someone in the above groups.

Health-care workers and volunteers should get the flu vaccine if they work with patients in any of the above groups.

Medicine for Prevention
Although the flu vaccine is the best way to prevent getting the flu, three antiviral medicines also are available by prescription that will help prevent flu infection. These include Tamiflu (oseltamivir), Flumadine (rimantadine) and Symmetrel (amantadine). The Food and Drug Administration has approved Tamiflu for use in adults and adolescents 13 years and older. Rimantadine and amantadine have been approved for use by adults and children who are 1 year of age and older.

Rimantadine and amantadine have unpleasant side effects. Your doctor can help you decide which medicine is best for you. You should discuss the flu vaccine and the medicines with your doctor before the flu season begins.

What is the Treatment for the Flu?
Many people treat their flu infections by simply resting in bed, drinking plenty of fluids and taking over-the-counter medicine such as aspirin or acetaminophen (Tylenol, for example). However, you should not give aspirin to children and adolescents who have the flu, as aspirin has been associated with Reye’s syndrome (see below). Further, you should not take antibiotics to treat the flu, because they do not work on viruses. Antibiotics only work against some infections caused by bacteria.

What are Possible Complications from the Flu?
You can have flu complications if you get a bacterial infection, which causes pneumonia in your weakened lungs. Pneumonia also can be caused by the flu virus itself. Symptoms of complications will usually appear after you start feeling better. After a brief period of improvement, you may suddenly develop high fever; shaking chills; chest pain with each breath; or coughing that produces thick, yellow-greenish-colored mucus.

Pneumonia can be a very serious and sometimes life-threatening condition. If you have any of these symptoms, you should contact your doctor immediately so that you can get the appropriate treatment.

Are There Other Flu Complications that Only Affect Children?
Reye’s syndrome, a condition that affects the nerves, sometimes develops in children and adolescents who are recovering from the flu. Reye’s syndrome begins with nausea and vomiting, but the progressive mental changes (such as confusion or delirium) cause the greatest concern. The syndrome often begins in young people after they take aspirin to get rid of fever or pain. Although very few children develop Reye’s syndrome, you should consult a doctor before giving aspirin or products that contain aspirin to children. Acetaminophen does not seem to be associated with Reye’s syndrome.

Other complications of the flu that affect children include convulsions caused by fever; croup; or ear infections, such as otitis media. Newborn babies recently out of intensive care units are particularly vulnerable to suffering from flu complications.

Are There Different Types of Flu Viruses?
The first flu virus was identified in the 1930s. Since then, scientists have classified flu viruses into types A, B, and C. Type A is the most common and usually causes the most serious epidemics. Type B outbreaks also can cause epidemics, but the disease it produces generally is milder than that caused by type A. Type C viruses, on the other hand, never have been connected with a large epidemic.

If a flu virus emerges that is either new or that has not circulated in many years, and if it is able to spread easily from person to person, it could quickly travel around the world and cause serious illness and death for millions of people. This is called a flu pandemic.

Although flu epidemics pop up in the fall and winter seasons in communities throughout the world every year, including the United States, there has not been a pandemic since 1968. Scientists are worried that a new flu virus will emerge in the 21st century and cause a severe pandemic again. For this reason, research institutions and health departments around the world are cooperating to track flu outbreaks in humans and animals, and to determine what types and strains of flu viruses are the causes.

Where Can I Get More Information About the Flu?
National Institute on Aging Information Center
1-800-222-2225
http://www.nih.gov/nia

Centers for Disease Control and Prevention
National Immunization Information Program
1-800-232-2522
http://www.cdc.gov/nip

Food and Drug Administration
HFI-40
Rockville, MD 20857
1-888-INFO-FDA (1-888-463-6332)
http://www.fda.gov