The influenza vaccine, commonly known as flu shot, offer protection against flu or influenza.The influenza virus or flu is a seasonal occurrence during winter. The virus affects the victim’s respiratory tract and may cause a wide range of complications. The most common symptom is severe illness and the virus is also estimated to cause anywhere between 250,000 to 500,000 deaths a year all over the world. In the US, the virus causes about 200,000 cases of hospitalization and about 41,000 deaths every year.
Influenza virus are of three types: the strong type A or type B virus and a milder type C virus. The influenza vaccine offers immunity against all these strands.
The influenza vaccination significantly reduces the risk of the person becoming infected with the influenza flu and provides immunity from influenza like illnesses. The immunity however takes about two weeks to set in and the vaccine does not protect against all strains of the flu. But the influenza vaccination may also offer cross protection against the H5N1 “avian influenza” and the H1N1 “swine flu” for some people.
A high dose vaccine is available for people above 65 years of age, to make amends for their weakened natural immunity.
Once administered, the influenza vaccine continues to provide immunity for many years. The vaccine itself however changes every year, and as such people in high risk of encountering the influenza virus are advised to take the influenza vaccine on an annual basis.
Influenza vaccinations not only provide immunity to those who take it, but also protect the society in general. Influenza is a contagious disease and if a person develops immunity, he or she also ceases to be a transmitter of this virus to others. For this reason, the United States has recommended influenza vaccinations for schoolchildren since 2006, and for that matter all people older than six months.
The origins of the influenza vaccine dates back to 1931 when Ernest William Goodpasture and his colleagues experimented with embryonated hens’ eggs at Vanderbilt University. Researchers such as Thomas Frances, Wilson Smith and Macfarlane Burnet followed up with this work and soon developed an experimental influenza vaccine. In the 1940s, during the course of World War II, the US military developed the first approved inactivated influenza vaccine. The vaccine was mass produced soon after the war. The US government pushed through the vaccination program in the aftermath of the 1976 swine flu scare.
Today the influenza vaccination is still egg-based and is available either as an injection (flu shot) or as a nasal spray. The US Food and Drug Administration (FDA) approved vaccination by nasal mist in March 2012 and since then this method is increasingly becoming popular compared to a flu shot. However, empirical evidence suggests that the flu shot is more effective than the nasal spray. Moreover the nasal spray method is not recommended for children below 2 years of age or adults above the age of 50.
The developments in the field of molecular technology have brought developing immunity to influenza through genetic manipulation of influenza genes within the realms of possibility. Experimentation are underway and such a breakthrough may emerge in the near future.