The flu (influenza) 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 this illness is by getting a flu vaccination each fall. On average, each year the United States experiences 5 percant to 20 percant of its population contracting the flu, leading to more than 200,000 persons hospitalized from complications and about 36,000 people who die as a result of complications related to flu.
Symptoms of flu include fever (usually high), headache, extreme tiredness, dry cough, sore throat, runny or stuffy nose, muscle aches and stomach symptoms such as nausea, vomiting and diarrhea, also can occur but are more common in children than adults. Complications of flu can include bacterial pneumonia, dehydration and worsening of chronic medical conditions, such as congestive heart failure, asthma, or diabetes. Children may experience sinus problems and ear infections.
Flu viruses are spread in respiratory droplets caused by coughing and sneezing. Although flu viruses usually spread from person to person, sometimes people become infected by touching something (such as a desk) with flu viruses on it and then touching their mouth or nose. Healthy adults may be able to infect others beginning one day before symptoms develop and up to five days after becoming sick. That means that you can pass on the flu to someone else before you know you are sick, as well as while you are sick.
The Centers for Disease Control (CDC) recommends that you wash your hands with soap and warm water for a minimum of 15 to 20 seconds. In the absence of soap and water, alcohol-based disposable hand wipes or gel sanitizers may be used. When using gel, rub your hands until the gel is dry. The gel doesn’t need water to work; the alcohol in it kills the germs on your hands.
The single best way to prevent flu is to get a flu vaccination each fall. The first of two types of vaccine are the “flu shot” – an inactivated vaccine (containing killed virus) that is given with a needle. The flu shot is approved for use in people older than 6 months, including healthy people and people with chronic medical conditions. The second type is the nasal-spray flu vaccine – a vaccine made with live, weakened flu viruses that do not cause the flu. The nasal-spray vaccine is approved for use in healthy people 5 years to 49 years of age who are not pregnant. About two weeks after vaccination, antibodies develop that protect against influenza virus infection.
The sources of information for this article are the CDC and the FDA/CFSAN Food Safety A to Z Reference Guide, September 2001: Hand washing.