Yesterday the question was raised in one of the Facebook groups if someone should get both the US and UK flu vaccines. It is a valid question if you do not know anything about flu vaccines. I worked in the Swine Flu Incident room in 2009 in the East of England Strategic Health Authority which is part of the NHS. I am no expert but this has given me a bit of an insight to how things work in response to emergencies.
First off the vaccines are the same. The World Health Organization predicts which three strains of flu will be prevalent during the flu season in the North Hemisphere and the manufacturers make them. So getting a flu shot on base and off base is not going to provide you with more protection and dangerous double dosing on vaccines. Also if you think about in this way, service members get the flu shot annually but they do not get another one when they reach their deployment base because they are covered. http://www.nhs.uk/Conditions/vaccinations/Pages/how-flu-vaccine-works.aspx
There are different approaches between the US and Europe on to how to distribute the flu vaccine. In America and Canada, anyone over six months old can get a flu shot. In Europe, nursing home residents, people with chronic medical conditions like asthma, the elderly, pregnant women, health care workers, and children from ages 6 months to 2 years, because they are more susceptible to the symptoms of the flu get the vaccine. America gives to everyone because if they look at the group that is suggested in Europe then about 75% of the population would meet the criteria and the patient pays for the vaccine. http://edition.cnn.com/2013/01/17/health/flu-vaccine-policy/
This varies for many reasons such as the lack of sick time in the US, whereas in Europe they have it. In Europe only doctors can give it out. I think that they often give it out in schools in the UK but this has to do with the NHS and the schools being part of the government's responsibility and saves the parents a trip!
Well if you ever thought about this, I hope I cleared it up!