How the Flu is Transmitted

Coughing and Sneezing are the Most Common Ways to Spread Influenza

Sep 4, 2009 John Wu

The spread of influenza viruses, such as swine flu, can be prevented by having everyone take some simple precautions, such as washing hands frequently.

The best way to prevent the flu is to not catch the influenza virus in the first place, regardless of whether or not one received the flu shot. Many health plans such as Kaiser Permanente offer free flu shots as a flu preventative measure. Even those who received flu vaccinations can help by doing their part to prevent the spread of influenza.

Spread of the 2009 H1N1 Swine Flu

The 2009 swine flu is a good example of why everyone needs to do their part to stop the spread of the flu virus. The annual flu vaccine in 2009 did not provide protection against the swine flu virus. A separate swine influenza vaccine is not expected to be ready until October 2009. Two flu shots against the influenza are needed in 2009, with the swine flu vaccine not available until after the 2009 flu season has already started.

On September 4, 2009, the Associated Press and the New York Times reported that over 2,000 students at Washington State University (WSU) contracted the swine flu during the first two weeks of classes. Because there is a football game between WSU and Stanford on September 5, 2009, there are concerns that the thousands more football fans could catch the swine flu if football fans do not practice flu prevention techniques. Authorities had to put in hand sanitizers at all concession stands in order to help prevent the spread of the swine flu virus.

In any year, the flu shot(s) may not cover all strains of the influenza virus. Therefore, it is still possible to catch the flu even though one has already received his annual flu shot.

How Does the Flu Virus Spread?

Respiratory droplets from a person who has the flu will usually contain the flu virus. Those droplets are expelled from the body via sneezing and coughing. In many cases, the hands of a person who has the flu make contact with their own respiratory droplets after a cough or sneeze. The unwashed hands then make contact with other people or frequently used objects such as door knobs or railings. An unwitting victim who does not wash or sanitizes their hands will then touch the door knob or railing with the flu virus, then touch another object with his hands such as food which allows the flu to enter his body.

The flu has an incubation period from one to four days, which means many people who do not know they have the flu will unknowingly transmit it to others if they don't wash their hands frequently while showing no flu symptoms.

Flu Prevention

The following activities should be practiced by everyone, including those with no symptoms, in order to limit the spread of flu, such as the H1N1 swine flu:

• Wash or sanitize hands frequently.
• Cover the nose and mouth when sneezing or coughing. Wear a mask if possible.
• Use tissues to remove respiratory secretions and dispose used tissues.
• Stay at least three feet away from others if infected with the flu virus. If it is possible to stay home, do so.

If everyone is able to take the above precautions, the spread of the flu can be minimized. Flu prevention efforts help classmates, co-workers, friends, family members, and others avoid catching the flu, regardless of whether there is vaccine protection or not.

References:

Centers for Disease Control and Prevention. "Key Facts About Swine Influenza (Swine Flu)."

Spickler, Anna Rovid. "Influenza Worksheet." Center for Food Security and Public Health at Iowa University.

Centers for Disease Control and Prevention. “Infection Control Measures for Preventing and Controlling Influenza Transmission in Health-care Facilities.”

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The copyright of the article How the Flu is Transmitted in General Medicine is owned by John Wu. Permission to republish How the Flu is Transmitted in print or online must be granted by the author in writing.

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