Facts About Seasonal Influenza

What Is Influenza (also called flu)?
The flu is a contagious respiratory illness caused by influenza viruses. It can cause mild to severe illness, and at times can lead to death. The best way to prevent the flu is by getting a flu vaccination each year.
Every year in the United States, on average:

• 5% to 20% of the population gets the flu;
• More than 200,000 people are hospitalized from flu complications; and
• About 36,000 people die from flu.

Some people, such as older people, young children, and people with certain health conditions (such as asthma, diabetes, or heart disease), are at high risk for serious flu complications.

How Flu Spreads
Person to Person
The main way that influenza viruses are spread is from person to person in respiratory droplets of coughs and sneezes. (This is called "droplet spread.") This can happen when droplets from a cough or sneeze of an infected person are propelled through the air and deposited on the mouth or nose of people nearby. Influenza viruses may also be spread when a person touches respiratory droplets on another person or an object and then touches their own mouth or nose (or someone else’s mouth or nose) before washing their hands.

The Flu Is Contagious
Most healthy adults may be able to infect others beginning 1 day before symptoms develop and up to 5 days after becoming sick. Children may pass the virus for longer than seven days. Symptoms start one to four days after the virus enters the body. That means that you may be able to pass on the flu to someone else before you know you are sick, as well as while you are sick. Some persons can be infected with the flu virus but have no symptoms. During this time, those persons can still spread the virus to others.

Preventing Seasonal Flu: Get Vaccinated
The single best way to prevent the flu is to get a flu vaccination each year. About two weeks after vaccination, antibodies develop that protect against influenza virus infection. Flu vaccines will not protect against flu-like illnesses caused by non-influenza viruses.

When to Get Vaccinated
Yearly flu vaccination should begin in September or as soon as vaccine is available and continue throughout the influenza season, into December, January, and beyond. This is because the timing and duration of influenza seasons vary. While influenza outbreaks can happen as early as October, most of the time influenza activity peaks in January or later.

In general, anyone who wants to reduce their chances of getting the flu can get vaccinated. However, certain people should get vaccinated each year either because they are at high risk of having serious flu-related complications or because they live with or care for high risk persons. During flu seasons when vaccine supplies are limited or delayed, the Advisory Committee on Immunization Practices (ACIP) makes recommendations regarding priority groups for vaccination.

Who Should Get Vaccinated
Emphasis should be placed on targeting giving the flu shot to persons at high risk for complications from influenza including:

• Persons aged 50 years (age eligibility may change according to vaccine availability
• All children 6 to 59 months of age
• All children between 5 and 18 years of age
• Persons aged 2 to 64 years with underlying chronic medical conditions
• All women who will be pregnant during the influenza season
• Children aged 6 months through 18 years on chronic aspirin therapy
• Persons who are contacts to those who are at risk for flu-related complications
• Health care workers involved in direct patient care
• Out-of-home caregivers and household contacts of children aged 6 months
• Residents of nursing homes and long-term care facilities

Please note that the Palomar Health community flu shot program is unable to vaccinate anyone under 18 years of age. Please see your pediatrician for flu shot clinics that can accomodate children.

Who Should Not Be Vaccinated
Some people should not be vaccinated without first consulting a physician. They include:

• People who have a severe allergy to chicken eggs.
• People who have had a severe reaction to an influenza vaccination in the past.
• People who developed Guillain-Barré syndrome (GBS) within 6 weeks of getting an influenza vaccine previously.
• Children less than 6 months of age (influenza vaccine is not approved for use in this age group).
• People who have a moderate or severe illness with a fever should wait to get vaccinated until their symptoms lessen.

Good Health Habits for Prevention
The single best way to prevent seasonal flu is to get vaccinated each year, but good health habits like covering your cough and washing your hands often can help prevent respiratory illnesses like the flu. There also are flu antiviral drugs that can be used to treat and prevent the flu.

• Avoid close contact. Avoid close contact with people who are sick. When you are sick, keep your distance from others to protect them from getting sick too.
• Stay home when you are sick.If possible, stay home from work, school, and errands when you are sick. You will help prevent others from catching your illness.
• Cover your mouth and nose.Cover your mouth and nose with a tissue when coughing or sneezing. It may prevent those around you from getting sick.
• Clean your hands.Washing your hands often will help protect you from germs.
• Avoid touching your eyes, nose or mouth.Germs are often spread when a person touches something that is contaminated with germs and then touches his or her eyes, nose, or mouth.
• Practice other good health habits.Get plenty of sleep, be physically active, manage your stress, drink plenty of fluids, and eat nutritious food.