What Is Flu/Colds? | HealthInfi

Overview

The flu, or influenza, is a viral disease of the respiratory tract—the nose, throat, bronchial tubes and lungs—and is highly contagious. It is spread though airborne droplets of moisture produced by coughs or sneezes. When you breathe these germs in through your nose or mouth, you may come down with the flu, generally within one to four days of exposure.

The flu is a potentially serious disease that can lead to hospitalization, or, in severe cases, death. Even healthy people can become very sick from the flu. Death rates from the flu vary from season to season. Flu-related deaths have ranged from a low of 3,000 to a high of 49,000 between 1976 and 2007, according to the U.S. Centers for Disease Control and Prevention (CDC). Outbreaks frequently start in school-age children, who carry the virus home and spread it to other groups.

And, beginning with the 2009-2010 flu season, there was a new flu to contend with—H1N1 flu (“swine flu”), which caused the first flu pandemic in more than 40 years. Since this outbreak, the seasonal flu vaccines have included coverage for the 2009 H1N1 flu. The seasonal trivalent flu vaccine usually contains one of each of the three kinds of influenza viruses that most commonly circulate among people today: influenza A (H1N1), influenza A (H3N2) and influenza B viruses. For the 2013-14 season, there are more flu vaccine options available than ever before. See thePrevention section for more information.

Flu seasons are unpredictable. The 2011-2012 flu season affected a record low number of people, but the 2012-2013 flu season was moderately severe. The flu season in the United States commonly peaks in January or February, but it can begin as early as October and continue into May. Because flu can be so serious and can spread so rapidly, the CDC recommends that everyone age 6 months and older get vaccinated every year. A yearly flu vaccine is the first and most important step in protecting against flu, according to the CDC.

Vaccines are especially important to those most susceptible to flu complications, including older people, children, pregnant women, people who are morbidly obese, people with compromised immune systems and those with chronic illnesses such as heart disease, kidney disease, asthma, COPD and diabetes. The most serious, often life-threatening complication of the flu is pneumonia. Other complications include ear infection, bronchitis, dehydration and worsening of chronic conditions, such as congestive heart failure, asthma or diabetes. Croup and a lung disease called bronchiolitis can also arise as complications in infants and young children.

In addition, the severity of illness is increased by exposure to cigarette smoke, which can injure airways and damage the cilia, the tiny hair-like structures that help keep airways clear. Toxic fumes, industrial smoke and other air pollutants are also risk factors.

There is also evidence that influenza can be more dangerous for women in their second or third trimester of pregnancy. The strain and stress of pregnancy on a woman’s lungs, combined with the type of influenza, can lead to pulmonary problems, although there doesn’t appear to be any danger to the fetus from the influenza virus itself.Read More