ideally, it should..
it is ALWAYS a safer option to get the flu shots when available every year.. but the flu is a unique problem that makes it difficult - sometimes impossible to force everyone to receive the flu shot..
in my country,
it is impossible for the government to provide the influenza vaccine for free and for everyone, like it does with the cost-effective and the readily-available Polio vaccine or the Measles vaccine..
unlike most vaccines,
a Flu shot is only effective for 6 months upto 12 months for most adults (children have their own schedule and they can receive multiple shots in less than 6 months).. this is compared to the Measles vaccine that can be effective for more than 20 years after 2 doses of MMR (of which measles are less dangerous in healthy adults)..
however, our Ministry of Health is offering the Flu vaccine for free to health-workers in government clinics and in government hospitals, and especially for those who deal with young children, with elderly (above 65 years old) and with really sick people on daily basis (for example: people with Asthma, COAD, heart disease and after chemotherapy)..
the way vaccines work,
they introduce the genetic make-up of a specific illness so our immune system can recognize the virus or the bacteria immediately and deal with the infection swiftly before they can cause harm - i.e. illness..
in a police metaphor, it would be very similar of distributing pictures of a wanted dangerous criminal to police stations all over the country, in addition to airports, sea-ports and border security..
when you receive the measles vaccine, billions of White Blood Cells in your blood and all over your body, are trained to identify the measles virus quickly and deal with them swiftly.. the same way that the police would be in a look out for a wanted criminal who is 6 feet tall with a unique facial scar and green-blue eyes.. and who is also armed and dangerous..
the criminal would wear a wig, coloured contact-lens, a fake moustache or a fake beard to fool the police, but the police are often trained to see through such disguises and successfully make a positive ID.. this is why most known vaccines, such as the Measles vaccine and the Polio vaccine are successful upto 97% of the time because even with minor changes in their genetic make-up, our body can correctly identify them and deal with the infection swiftly before they can cause any real harm..
the problem with the seasonal or the common flu that it changes its genetic make-up significantly and it changes too frequently (almost every year and sometimes every season) to escape detection by our body's defences..
imagine a criminal who undergoes a drastic plastic surgery every year: so one year he is a man with a moustache, the next year he is a woman, the next year he is an Asian elderly..
older pictures of the criminal would be useless after such surgeries because they hold little resemblance of what they look like now..
and because the Flu virus changes its genetic make up too frequently, the pharmaceutical companies must research and develop newer vaccines every year (and sometimes every season)..
and to make things worse, most vaccines last months and years..
experts however recommend getting flu-shots every year and sometimes every 6 months..
it would be a very expensive issue, if the government mandates the flu shots every year (and sometimes every 6 months) for everyone!!..
and since the flu vaccine changes frequently, it makes it harder to convince pharmacies to order a whole lot of them and keep them in storage for long without use as it may lose its relevance the next year and sometimes the next season..
and at the end;
you have to remember that the seasonal flu or the common flu is NOT life-threatening condition to most people.. yes, 3000 to 49000 Americans die from influenza every year, but the Flu is still considerably less dangerous and more treatable than Polio or Measles..
most people who get the flu, could get sick for 5 days and upto 14 days before they become fine; this is compared to the debilitating Polio and the extremely infectious and the very deadly Measles..