There are several types of influenza vaccines, including the influenza A (H1N1) pdm09 and the H3N2 virus. These vaccines protect against influenza A, H3N2, B, and C viruses, which cause the flu. Flu-Mist and Fluzone/Flu-Mist Quadrivalent are two brands of influenza vaccines. Flu-Mist Quadrivalent are nasal-attenuated vaccine, while Influvac is a surface-antigen subunit vaccine. Other vaccines include Fluquadri, Afluria, and Fluquadri.
The composition of influenza vaccines is updated each year by the World Health Organization (WHO), using information collected from GISRS, an international collaboration of 141 national influenza centers in 111 countries, four essential regulatory laboratories of the WHO, and the European Medicines Agency. These organizations analyze samples collected from various parts of the world and make recommendations for vaccination. In some countries, Seasonal Influenza Vaccines are recommended for people with certain health conditions or who are immune-compromised. Flu vaccines have proven to reduce the health burden of seasonal influenza.
The inactivated influenza vaccines have been available for decades and are given via intramuscular injection to adults and children six months and older. NanoFlu is a quadrivalent hemagglutinin protein nanoparticle influenza vaccine developed by Novavax. The vaccine employs H.A. amino acid protein sequences and Novavax's patented Matrix-M(TM) adjuvant. Cidara Therapeutics Inc. has invested in a Waltham, Mass. facility to develop a seasonal influenza vaccine candidate, CVSQIV. Inactivated influenza vaccines are safe for women at any stage of pregnancy and are also recommended for health care workers. Inactivated influenza vaccines must be stored in the original cardboard packaging.
Seasonal influenza vaccines are made using egg-based, cell-based, and recombinant influenza viruses. CDC's safety summary includes information on the vaccine's adverse effects, vaccination contraindications, and screening. This information can help physicians determine the right vaccination for their patients. Despite the benefits of seasonal influenza vaccines, the vaccines still carry a risk of causing flu symptoms. The same goes for other respiratory viruses. Several respiratory viruses mimic flu symptoms and are also widespread during flu season.