MISSISSIPPI STATE -- Health professionals usually recommend flu shots primarily for at-risk groups, but this year will be a good year for greater numbers to consider increased protection.

Each year, the Centers for Disease Control and Prevention places certain people at higher risk for catching the flu. These include people over the age of 65, or those with heart or lung disease, diabetes, thyroid problems, asthma, anemia, weakened immune systems and respiratory disorders. Also people in close contact with high-risk individuals should be vaccinated for their protection and their contacts.

"Anyone can be infected with the flu, and everyone can benefit from the flu vaccine," said Linda Patterson, a registered nurse and health education specialist with Mississippi State University's Extension Service.

Inhalation anthrax with its flu-like symptoms and other forms of anthrax may be making all the headlines, but the bigger threat this winter is from the flu. Dr. David Satcher, the U.S. Surgeon General, recently reported that the flu caused 20,000 deaths nationwide last year and 100,000 hospitalizations.

Influenza is an acute respiratory infection, and its symptoms usually include fever, aches, chills, weakness, loss of appetite, and aching of the head, back, arms and legs. In addition, a sore throat and dry cough, nausea and burning eyes may accompany the virus.

"While we certainly hope anthrax does not continue to preoccupy our thoughts, a flu shot can prevent unnecessary fear of symptoms that are common to both diseases," Patterson said. "If you don't have the flu at all, you won't have to worry about the symptoms. Fear and stress can work against the body's natural defenses."

Patterson said scientists work each year to develop a new vaccine that reflects the different types of influenza from the previous year. Each year the names change and the types of flu differ. The fact that a person can be infected with more than one type of influenza prevents the vaccine from being guaranteed protection.

Patterson said no vaccine is 100 percent effective, but a flu shot offers the best protection. The vaccine may cause side effects such as soreness at the injection site, and in rare cases, fever and fatigue.

"These effects are the result of the body actually building immunity," Patterson said.

The flu is transmitted by airborne droplets of respiratory fluids produced by sneezes and coughing. These droplets infect another person by entering into the eyes, nose or mouth. Flu season runs from December until March. A flu shot is most effective before the season begins.

Sometimes flu symptoms appear after immunization and the flu shot is blamed. People can be exposed to infection at any time, including shortly before and after the shot. In these cases, the body has not yet had enough time to increase its immunity.

Call a physician within the first 24 hours of the appearance of flu symptoms, and a prescription medicine can greatly decrease the severity of illness.

"Complications of the flu such as pneumonia and serious lung infections are great threats to high-risk people. These flu complications are greater threats for them than the virus itself," Patterson said.

Those people with allergic reactions to egg and egg products should consult a physician before being vaccinated, because egg products are used in vaccine production.