Types of Flu Vaccines

The two influenza vaccine wake forest north carolina types that have widespread availability are live attenuated influenza vaccines (LAIV) and inactivated influenza vaccines (IIV).  Traditionally, both influenza vaccine types have been made in order to safeguard against three seasonal flu virus strains (known as trivalent vaccines).  In the majority of countries, this remains the case and current trivalent vaccines contain pandemic A (H1N1), influenza A (H3N2), and one of two influenza B viruses.  More recently, vaccines are available in some countries that protect against four viruses (quadrivalent vaccines), including both strains of influenza B virus.  Whatever the composition or type of seasonal flu vaccine available, the vaccine is recommended to be received every year in order to provide ideal protection against the influenza virus. Heritage provides the four virus (quadrivalent vaccine) in order to provide the most protection available.

The World Health Organization (WHO), updates the composition of the vaccines annually based on data obtained from samples gathered by the Global Influenza Surveillance and Response System (GISRS).  The GISRS collects flu virus samples on a continual basis in order to advise on the virus strains most likely to be applicable during the upcoming flu season.  Based on this information, the influenza vaccines are manufactured and typically take about six months to produce.  Because of the time pressure associated with vaccine production, timely submission of virus strains to the GISRS is of the upmost importance.

Inactivated Influenza Vaccines (IIV)

Approved for use in people six months of age and older, IIV can also be used for patients with chronic underlying medical conditions and pregnant women.  Vaccination from influenza during pregnancy, helps protect both the mother and newborn against the flu virus.  IIV is injected in the deltoid (upper arm/shoulder) muscle and a single dose is generally recommended.  However, if the patient is six months to eight years old and did not received a seasonal flu vaccine during the last flu season, they should be administered two doses at least four weeks apart.

As the name suggests, the viruses contained in IIV vaccines are inactive.  As such, they do not cause the flu but may occasionally result in manageable side effects such as a local reaction at the site of injection.  People that have never received an influenza vaccine before, and therefore have not been exposed to the flu vaccine antigens, could experience malaise, transient fever, muscle pain, and other adverse systemic events. Yearly the constituent of the virus in the vaccine may change. Heritage stays current on these guidelines and provides the most recent and most potent for of the vaccine available each year.

Live Attenuated Influenza Vaccines (LAIV)

LAIV is only recommended for use on patients between 2 to 49 years of age that do not have underlying chronic  respiratory related medical conditions such as Asthma or COPD.  Whereas IIV is safe for use on women who are pregnant, LAIV is not.  LAIV is administered via a nasal spray in a single dose.  Similar to the restrictions associated with IIV, children ages two to eight that did not receive a seasonal flu vaccine in the previous season, should be administered two doses at least four weeks apart.

The viruses in LAIV are attenuated (weakened) and do not cause the flu.  Side effects are typically mild and may include rhinorrhoea (nasal congestion), sore throat, or fever.  Compared to the symptoms of an influenza infection, most of the side effects are transient and mild.

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