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Influenza and Flu Shots

Influenza and Flu Shots Tekton Research

Influenza – or simply “the flu” – refers to a family of viruses that attacks mammals and birds.  Although it is common to refer to getting “the flu,” there are actually a number of different strains of influenza, some of which are more dangerous than others.  The symptoms of influenza include fever, chills, muscle pain, weakness, and sometimes nausea.  While some of these symptoms bear a similarity to the common cold, which is also a virus, the flu is more severe than the cold.

Famous Strains of Influenza

Swine flu has received a great deal of media attention recently, much like the bird flu before it.  However, these flus both proved to be relatively mild compared to past strains of influenza.  The reason swine flu triggered such a panic is because it is the type of flu known as H1N1 – the type that triggered the Spanish flu pandemic of 1918.

A worldwide outbreak that touched nearly every part of the world, the Spanish flu lasted two years and took the lives of an estimated 100 million people.  During the course of the pandemic, 500 million people – or one third of the world’s total population – became infected.

All other deadly flu pandemics have arisen from a similar strain of influenza as the Spanish flu.  H1N1 is part of the larger family of influenza strains referred to as “Influenzavirus A.”  Other strains of influenza (Influenzaviruses B and C) tend to be less severe than the viruses of Influenzavirus A.  While Influenzavirus A is seen most typically in birds, when it crosses over into the human population, the results can be devastating.

Development of the Flu Vaccine and the Flu Shot

The Spanish flu pandemic of 1918 was an incident that the world did not want to repeat.  Physicians had experimented with different flu vaccines since the sixteenth century, but in the 1940s the US military developed the first effective flu vaccine.

Since that time, two flu vaccines have been developed.  The first is the flu shot, the most well-known and popular type of vaccination against influenza.  The flu shot contains a dead influenza virus that functions to teach the body how to recognize and fight the virus.  According to the Centers for Disease Control and Prevention (CDC), the flu shot is safe for both healthy people and people with chronic medical conditions.

More recently, a nasal spray flu vaccine has been developed.  Unlike the flu shot, the nasal spray uses live influenza viruses that have been weakened.  By contrast to the flu shot, this flu vaccine is approved only for healthy people between the ages of 2 and 49.

Benefits and Limitations of the Flu Shot

The flu shot and the nasal spray flu vaccine protect people against the deadly H1N1 virus, the H3N2 virus (which caused the Hong Kong flu pandemic in the late 1960s), and one strain of Influenzavirus B.  In essence, then, people who take the flu shot or who take the nasal spray flu vaccine are protected from the worst strains of influenza, but still may catch another strain.  In other words, the flu shot and nasal spray flu vaccine does not guarantee that the person taking it will not get sick during that year’s flu season.

Getting Vaccinated Each Year

It is recommended that some people should definitely take a flu shot or nasal spray flu vaccine each year, while other people are recommended not to take a flu vaccine at all.

According to the CDC, the following people should get vaccinated each year:

  • Health care workers and home caregivers
  • Children older than six months
  • Pregnant women
  • People over age 50
  • Residents of nursing homes
  • People with particular chronic health conditions

The CDC recommends against the following people getting vaccinated:

  • Anyone with an allergy to chicken eggs
  • Anyone who has previously had an allergic reaction to the flu vaccine
  • Anyone with Guillian-Barre syndrome
  • People who are currently ill
  • Children younger than six months

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