Hey, you should get vaccinated!

We are in the midst of the 5th unofficial season, flu season. Flu, short for Influenza is a viral infection of the lower respiratory track. The flu season, occurs each year due to antigenic drift. During replication, a mutation often only changes one amino acid in the within the spikes of the influenza virus. However this one minuscule change is responsible for each flu season having a slightly different strain of the flu. So do you know what is important? Receiving your flu vaccination every flu season, because the immunity your body gained to the flu last year will not be as effective or effective at all to this new strain. Although little protection is better than none, wouldn’t more be better than a little. The CDC suggests that the flu reduces the risk of illness by 40%-60% among the overall population when the vaccine viruses are representative to those spreading in the community. Getting your flu shot is not just protecting you, but those around you because influenza is obtained by inhaling aerosolized respiratory secretions or from fomites. So the less you spread the flu, the less others around you can get it.

The trivalent flu vaccine for the 2019-2020 flu will protect against the following 3 strains of the flu:

• A/Brisbane/02/2018 (H1N1)pdm09-like virus
• A/Kansas/14/2017 (H3N2)-like virus
• B/Colorado/06/2017-like (Victoria Lineage) virus

The quadrivalent vaccine contains the the 3 viruses above and the following:

• B/Phuket/3073/2013-like (Yamagata Lineage) virus

Extensive research is done by the FDA’s Vaccines and Related Biological Products Advisory Committee (VRBPAC) to suggest the strains of flu that will be most common each year. Then they come to a consensus on which strains should be considered in the the vaccines.

There is something great about the flu shot besides the protection from the flu. There are multiple options for the flu shot:

• Standard dose flue shot: inactivated influenza vaccine
• High-dose shots: for people 65 and older
  • High dose shots contain four times the antigen of standard flu shots. Antigen is the component of the vaccine that helps the body build up protection. It is developed to give older people a better immune response to the flu.
• Shots with adjuvant: for people 65 years and older
  • Adjuvant is a component that helps create a stronger immune response.
• Shots made with virus grown in cell culture: no eggs involved
  • For those allergic to eggs because most inactivated influenza vaccines are made by growing the virus in eggs.
• Shots that are made with a vaccine production technology that actually does not require the use of the flu virus
  • Vaccines are created synthetically. By injecting a host line cell with the virus DNA for making hemagglutinin which triggers the human body to create antibodies to target the virus and a baculovirus. This recombinant virus causes the host line cells to rapidly produce the HA antigen then the antigen is collected in bulk and repackaged as the vaccine. It does not use eggs.
• Live attenuated influenza vaccine (LAIV): attenuated live virus given by nasal spray
  • this option is not available for the 2019-2020 season

So if you are older, scared of needles, or allergic to eggs there really is no excuse to not get your flu vaccine because look at all the options you have. Be sure to talk to your health care provider regarding the proper flu vaccination for you. Therefore you can protect yourself and protect those who cannot protect themselves. Those under the age of 6 months should not receive the vaccine.

The CDC does not have the flu vaccine effectiveness estimates for the season yet. However the flu’s antigenic characterization is updated in FluView each week. The most important updates is that indicators of overall severity are not high at the point in the season. Visits to healthcare providers for flu like illness was at 6%. The mortality rate for deaths attributed to pneumonia and influenza is 7.1% for it to be an epidemic it must be at 7.2%. CDC estimates that there has been 22 million flu illnesses and 12,000 deaths from the flu so far this season. Still the flu vaccination is the BEST way to prevent the flu and its serious complication.

If you do think you have come down with the flu it is important to stay home and rest because most people have mild illness and do not need medical care. However if you are at high risk of flu complications it is important to see your doctor for an antiviral drugs. They work best when begun within 48 hours of getting sick. If you do not have high risk, it is up to the discretion of your health care provider to prescribe you a antiviral drug.

Overall, the influenza vaccine CANNOT cause the influenza virus. However it is still possible to obtain the flu even if you did get vaccinated. It is possible if you were exposed to the virus shortly before you were vaccinated or before the body gained protection. Or you have been exposed to a flu virus not in the vaccine. The protection of the flu vaccine varies widely and strongly is based on the immune system of the individual. So please do not blame the flu shot for you coming down with the flu. There are many outside factors that can cause the flu and the flu shot is not one. Protect yourself this flu season wash your hands often, stay away from those with the flu and most importantly get your flu shot!!!