Phooey on the Flu-y

October 9, 2013 2:58 PM

Can I get a second flu vaccine if the first one I got is not what I originally wanted to get, and if so, is it worth doing that?

I read that some of the flu vaccines (including injection type) in the US this year cover four strains instead of three strains. Logically that sounds better to me (more strains = more protection = better) and my medical group confirmed they were using the four strain type, so I got my shot today. But then when I asked them to reconfirm it was the four strain type, they said they only have the three strain type.

Their ostensible reason for only having the three strain type was because they believe there is not sufficient evidence that the four strain type is more effective. I suspect maybe the real reason is because of something related to cost/insurance coverage (or availability, but they never mentioned anything about being unable to get it) since if it's no more expensive and no less safe and it holds the possibility of providing more protection, why not use it?

Are there any doctors and nurses here who can shed any light on that topic, as well as inform me whether it would be generally considered safe among the medical community for a middle aged healthy patient to get another shot that covers four strains now that I've already had one shot (specifically FluLaval)?

Thank you.

posted by Dansaman to Health & Fitness (3 answers total)

The quadrivalent (4-strain) vaccine is considerably more expensive and in fact (since this is the first year it's been offered) there is no data to show that it provides any real clinical benefit over the trivalent (3-strain) version. I don't know if insurance companies are reimbursing it differently; I would suspect not.

There are very very few comtraindications to the flu shot and I can't think of any reason that a second dose would be a problem unless you have a history of anaphylaxis to a component. In fact, children getting their first flu vaccine are supposed to get 2 doses 4 weeks apart to consolidate the immune response.

Note:I am not your doctor; this is not medical advice.
posted by The Elusive Architeuthis at 4:01 PM on October 9, 2013

The nasal mist vaccine is *only* quadrivalent, so if you get that, you're certain to get all four.
posted by yellowcandy at 10:37 PM on October 9, 2013

You're unlikely to experience any problems from a second shot. But I wouldn't bother with the second shot.

The strains that go into flu shots are selected on the basis of what is likely to show up this season (based in turn on what is going on in the other hemisphere during their flu season and a bit of educated guesswork). I don't know what is the "missing" strain that is present in the quadrivalent, but it is probably the one you are least likely to encounter.

Second, flu vaccination is more about protecting the herd than a particular individual. That is, vaccinations main purpose is reduce the overall number of infected people and thus protect all people from infection by making it less likely that they will met an infected person (as opposed to giving them resistance against an infection opportunity). Vaccination to protect an individual is usually advised only when the subject is elderly, weak, sick or comes into regular contact with people that are elderly, etc.

As a healthy middle-aged person, your vaccination is more about protecting the herd than yourself. There's little call for the marginal benefit that a second treatment would give.
posted by outlier at 2:43 AM on October 10, 2013