To Prevent the Flu, Schedule Vaccine Now

Influenza is a respiratory infection caused by a virus. In general, influenza viruses will cause a more severe illness than other infections such as the common cold. Unlike a cold, which usually begins slowly and often runs its course without a fever, flu symptoms typically include a sudden headache with a dry cough, muscle aches, fatigue, chills and a fever (usually 100ºF to 103ºF in adults or even higher in children). Flu sufferers might also experience a sore throat and a runny or stuffy nose.

Nausea, vomiting and diarrhea are not typical symptoms of the flu, but might accompany influenza infection, especially in children. Even though the term "stomach flu" is widely used, most gastrointestinal illnesses are caused by organisms other than influenza viruses. (Often the culprit is found in contaminated food, which by some estimates sickens 76 million Americans every year.)

When the flu season hits us - and it will - is there any way to avoid the worst of it?

The simplest and surest way to avoid getting the flu is to be vaccinated against it. Most commonly, people receive "flu shots," but since 2003, FluMist - a flu vaccine that's sprayed into the nose - has been available for use in healthy people between the ages of 5 and 49.

Both the injected and the nasally-administered vaccines contain pieces of influenza viruses. These components cause the immune system to build defenses and provide protection against the real virus when it enters the body. Injected flu vaccine is made from killed flu viruses, while FluMist contains live (but very weak) viruses. This means there is a theoretical chance that the spray vaccine could cause the or spread the flu in children under 5 years of age, pregnant women, people over 50 years of age, or those who are weakened by illness or medical treatments.

Preventive methods such as frequent hand washing or avoiding contact with other people are generally helpful in avoiding illness, but less effective in stopping a flu outbreak once it has begun. Influenza virus spreads easily and can be transmitted through the air or on surfaces; this means you can acquire the flu just by breathing the same air or touching the same objects as someone who has the flu.

Whether you've received a flu vaccine or not, it's a good idea to make good use of antiviral wipes and lotions to prevent germ transmission from hands, telephones, and other surfaces. Wash hands frequently, and don't touch your mouth, nose, or eyes - all common routes for germ transmission. Use tissues or your arm to cover coughs or sneezes.

High-Risk Populations
According to the CDC, influenza is associated with more than 226,000 hospitalizations and 36,000 deaths nationwide each year. In general, anyone who wants to reduce their chances of getting the flu can get vaccinated, but flu-related complications are much more likely to develop among the elderly and people with chronic health problems. This is why the CDC's Advisory Committee on Immunization Practices (ACIP) recommends that people who are at high risk of having serious flu complications or people who live with or care for those at high risk for serious complications should get vaccinated each year. These groups include:

• People 50 years of age or older.
• All children 6 months to 5 years of age.
• Adults and children with diabetes or chronic diseases of the heart, lungs, or kidneys.
• People living in long-term care facilities and group homes.
• Health care workers.
• Women who will be pregnant during the flu season.
• Those with weak immune systems due to situations such as cancer chemotherapy or HIV infection.
• People with any condition that can compromise respiratory function or the handling of respiratory secretions (that is, a condition that makes it hard to breathe or swallow, such as brain injury or disease, spinal cord injuries, seizure disorders, or other nerve or muscle disorders.)

People in these groups should make a special effort to receive the flu vaccine as soon as it becomes available in their area. Wisconsin residents who still want to be vaccinated should first check to make sure their health care provider has flu vaccine on hand - shortages have been reported in the past, although none are predicted for this year. To find a location that's offering flu vaccinations, try contacting your local Health Department.

Vaccination Side Effects
The most common side effect of injected flu vaccination is soreness at the site of the injection - flu vaccine is typically administered to adults in the arm and to children in the thigh. Some people (especially children who have not previously been exposed to the flu virus) may experience fever, tiredness or sore muscles. These side effects may begin six to 12 hours after vaccination and might last for up to two days. One important warning: because chicken eggs are used as part of the flu vaccine production process, people who are allergic to egg protein should not receive the vaccine.

The most common side effects of nasal-spray flu vaccine in children can include runny nose, headache, vomiting, muscle aches, and fever. In adults, side effects can include runny nose, headache, sore throat, and cough. Fever is not a common side effect in adults receiving the nasal-spray flu vaccine.

Antiviral Medications for Treatment and Prevention
If you realize you are coming down with the flu and can visit your health care provider within the first two days of symptoms, there are three FDA-approved oral prescription medications available in the US - amantadine (brand name Symmetrel), rimantadine (Flumadine), and oseltamivir (Tamiflu) - that can lessen the severity and duration of the illness.

In addition, an inhaled anti-viral drug, zanamivir (Relenza), is approved and available for those aged 7 years and older for the treatment of uncomplicated influenza virus. Relenza can cause problems for people with asthma or chronic obstructive pulmonary disease (COPD). Clinical studies showed that for the drug to be effective, patients needed to start treatment within two days of the onset of symptoms.

When used within 2 days after becoming sick, these medications can reduce influenza symptoms and may shorten the time you are sick by 1 or 2 days. They also may make you less contagious. All of these medications must be prescribed by a doctor and taken for 3-5 consecutive days. The medications are effective only against influenza viruses; they will not help symptoms associated with the common cold or viruses.

In addition to their use as treatments for the flu, all four medications also are approved for prevention of influenza. When used for prevention, they are about 70% to 90% effective in preventing illness in healthy adults.

All of the antiviral medications may be effective for influenza A viruses. However, only oseltamivir and zanamivir are effective for influenza B viruses. Recent evidence indicates that a high proportion of influenza A viruses in the United States have developed resistance to amantadine and rimantadine. Your doctor can help decide whether you should take an antiviral drug and which one you should use.

Easing Flu Symptoms
If you don't receive a flu vaccine and start having symptoms - pounding head, muscle aches, temperature higher than 100°, fatigue - what do you do? Most of us know the answer to this one: stay in bed, drink plenty of fluids, and take advantage of pain relievers like acetaminophen or ibuprofen. (Because of its association with a rare condition called Reye Syndrome, aspirin or aspirin-containing products should never be given to children who are recovering from viral illnesses such as flu or chickenpox.)

People who have the flu usually feel better in two or three days, although the fatigue and cough can linger for two weeks or more. In most cases recovery is complete, but some sufferers develop serious medical complications such as pneumonia. If your illness becomes worse or refuses to clear up, or if you have new or severe symptoms, you should see your health care provider.

Eileen Early, RN, BSN
HealthLink Editor

This article includes information from the US Centers for Disease Control and Prevention (CDC) and the National Institute of Allergy and Infectious Diseases.

Each year, Medical College of Wisconsin physicians care for more than 180,000 patients, representing nearly 500,000 patient visits. Medical College physicians practice at Children's Hospital of Wisconsin, Froedtert Memorial Lutheran Hospital, the Milwaukee VA Medical Center, and many other hospitals and clinics in Milwaukee and southeastern Wisconsin.