By Ann J. Curley
CNN Medical Assignment Manager

Many of our readers are still asking questions about H1N1 and seasonal influenza. Today we’ve got a question from Patty:

I am a 63-year-old health care worker in relatively good health, and I’m caring for a 2-month-old infant (my granddaughter). I have had a reaction to thimerosal in the past. It was used as a preservative in contact lens solution.

Is thimerosal used as a preservative in either seasonal flu vaccine or H1N1 vaccine? Are there available alternatives to these vaccines? How would I access them?

Thanks,
Patty Holly

Patty,

Thank you for your question. It’s important that you make your health care provider aware of your sensitivity to thimerosal, which is a preservative used in many products, including some vaccines, nasal products, and eye solutions.

According to the Centers for Disease Control and Prevention, the 2009 H1N1 influenza vaccines approved by the FDA are being manufactured with and without thimerosal.

Multi-dose vials of flu vaccine need to contain a preservative to prevent bacterial contamination, which can occur when multiple syringes are inserted into the same bottle.  However, some manufacturers also produce single-dose flu shots, which do not require any preservatives.

The nasal flu vaccine – both for seasonal flu and H1N1 – is always thimerosal-free. However, it is recommended only for people ages 2 to 49 who have no underlying health problems. The nasal spray vaccine is made from a weakened live virus and is not recommended for people with autoimmune disorders, pregnant women, and patients with certain chronic health problems, including diabetes, heart disease, asthma, and lung disease. Unfortunately, you can’t take the nasal flu vaccine because you are 63. You can find more information about the live vaccine here .

Ask your doctor for a thimerosal-free flu shot. If he or she doesn’t have one, you can visit the CDC’s H1N1 Web site and check out its “flu shot locator” .  It has links to the Web site of each state’s health department, with specific information about where vaccine can be found.

The Centers for Disease Control and Prevention has a lot of useful information about both seasonal flu and H1N1 flu on its Web site . Also be sure to check out CNN.com’s flu page .

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