Get Ready Mailbag: Do I need a flu shot if I have had H1N1?

Welcome to another installment of the Get Ready Mailbag, when we take time to answer questions sent our way by readers like you. Have a question you want answered? Send an e-mail to getready@apha.org.

I think I already had H1N1 flu, aka swine flu. Should I still get the vaccine? How do I know for sure that I’ve had H1N1?

Unless you know 100 percent for sure that you had H1N1 flu — by way of a lab-confirmed test — you should still get vaccinated, according to federal flu experts. Most people who have had flu-like illnesses since March 2009 (when H1N1 was first recognized) don’t know for sure that it was the flu, or whether it was H1N1.

If you absolutely positively want to know whether you’ve had H1N1 or any other specific flu strain, you’d need a special test, called the "RT-PCR" to confirm it. Such tests are often used in clinical settings such as hospitals to help health workers decide how to treat really sick patients. However, they aren’t generally recommended for people who’ve had regular flu symptoms and don’t need special care, so your doctor will probably tell you that you don’t need the test.

And even if it does turn out that you’ve had H1N1 — and possibly developed full or partial immunity to the virus — getting the vaccination won’t harm you. Talk to your doctor about whether you should get the vaccination, as certain people are at higher risk of getting sick from H1N1. The bottom line? It’s always better to be safe than sorry.