Note: The author presumes that you have read the disclaimer at the bottom of this blog if you have read this note and subsequent article.
Ever wondered why you vaccinated every year against influenza? Well, a short answer is changes in the virus composition that occurs every year. A long answer provides the small changes that occur in the Type A & B virus strain (called antigenic shift) or a major change that occurs in Type A or Type B viruses. Multiple flu viruses circulate each year and serial infections with different strains in the same person in a single season are possible.
Why should it matter?
Flu is caused by influenza viruses, and is spread mainly by coughing, sneezing, and close contact. Anyone can get flu. Flu strikes suddenly and can last several days. Especially for those who are vulnerable, it may have prolonged and severe problems. You should consult your doctors for understanding your vulnerability. However, generally Flu is a cause of concern for young children, people 65 years of age and older, pregnant women, and people with preexisting heart of lung conditions or a weakened immune system are at greatest risk.
As noted earlier, all those vulnerable are vaccinated early on in the winter against a combination of Type A and Type B virus. Since those small changes occur every year (antigenic drift) so a new vaccine is made every year. Generally every 3 – 5 years, the virus undergoes major mutations and since the population is not exposed to these new viruses, they are vulnerable (called absence of herd immunity in medical parlance) and results in pandemic.
How do scientists predict the right combination for the upcoming year?
While the Northern hemisphere is going through its summer and hurricane/tornado season, the Southern hemisphere, that includes Australia and New Zealand, are already undergoing winter with epidemic or endemic existence of Influenza. These same virus travel north, along with international travelers, and infect the population Northern hemisphere during their winter.
What is the prediction for 2017?
If you look at the prevalence of Influenza in Australia and New Zealand, the severity as well as the incidence if 2.5 folds more as compared to earlier year. That portends ominous signs for the Northern hemisphere winter.
What do we do?
Well, a simple answer is get vaccinated on time. Ideal time is before the onset of winter. Ideally, for full immunity to take effect, you need to give at least two weeks for the body to respond. So, if we are presuming the virus to start spreading and infecting the population, you should ideally take the vaccine at least by Sept end.
Who should be vaccinated?
According to CDC barring those with reaction to influenza vaccine and children less than 6 months of age, should not be vaccinated. According to CDC (Center for Disease Control) ‘everyone 6 months of age and older are recommended to get the flu vaccine, including even the healthiest adults. Vaccination is especially important for people at high risk of serious influenza complications or people who live with or care for people at higher risk for serious complications’.
This is voluntary awareness service program. You should consult your health care professionals for determining the timing, indications, type and amount of dose. Efforts for this awareness are voluntary and not supported by any commercial or other organizations. Readers are advised and encouraged to discuss any health related issues with their doctors.
To understand the difference between Flu, Cold and Allergy, visit link here from Harford County Health