Influenza Vaccine: What is it?
Influenza vaccine, also known as flu vaccine is a shot that protects you from the flu virus. The flu vaccine is the best protection against flu. The flu can be a very serious illness, especially in young children, adults ages 65 and over, those with underlying health conditions, and pregnant women.
In the United States, flu shots are recommended for everyone ages 6 months and older, according to the Centers for Disease Control and Prevention.
Strains of the flu virus are constantly changing, so a new flu vaccine is made each year. Scientists make the vaccine before flu season starts by predicting which flu strains are likely to be the most common during the upcoming season. According to Dr. William Schaffner, a preventive medicine and infectious disease expert at the Vanderbilt University School of Medicine, 
Since the flu virus frequently drifts in its genetic composition, you have to reformate the vaccine, and this is one of the reason that people have to [get a flu shot] on an annual basis.”
You normally get it in your arm, but you can also get it as a nasal spray. It’s made from the three or four flu viruses that are most likely to make you sick during the upcoming year.
The most common strains of the influenza virus in 2014 were recorded to be H3N2 varieties, known for causing more deaths, illnesses and hospitalizations than other flu strains.
Image Credits: medscape, guardianlv, vaccinenewsdaily
