Update on Flu Shots

There were more than 80,000 flu-related deaths in the United States last winter.

Do I have to worry about the effect of any ingredients?  In the past, people with egg allergies had to take special precautions when getting flu shots because many of the viruses used in vaccines are grown in eggs.  As of the 2016-17 season, those with a history of “egg allergies of any severity” may receive any licensed flu vaccine appropriate for their age group, the CDC says.  Those with a history of severe allergic reactions — more than just hives — should get the vaccine in a medical setting.

Some people worry about whether flu shots contain thimerosal, an additive containing ethylmercury that is no longer used in any children’s vaccines.  Thimerosal is still used to help prevent the growth of germs in vaccine vials that contain multiple doses.  Vaccine experts, and the CDC, say this use is safe.   But because many flu shots are single dose, thimerosal is often not an issue for adults either.

How effective are flu shots?   Because it takes at least six month to make and distribute the shots that become available in September, scientists have to make their best guess about which strains will circulate, and thus what to include in a vaccine, well in advance.  During that time, and even while vaccines are being produced, the circulating viruses can mutate, lessening the effectiveness of the chosen vaccine.  It’s an imperfect science.

In the 2014-15 season, the vaccine was only 19 percent effective.  Last flu season, the overall vaccine effectiveness against both influenza A and B viruses was estimated to be 40 percent.  In other words, it reduced your risk of having to seek medical care for the flu by 40 percent, according to the CDC.

Paying for your vaccine.  Most people with health insurance that complies with the Affordable Care Act are entitled to a flu shot without a co-payment or coinsurance.  Medicare beneficiaries’ flu shots are covered under Part B; beneficiaries pay nothing as long as the doctor or other provider accepts Medicare.

Medicaid covers flu shots for children and young adults through age 20.  Adults eligible for Medicaid are also generally covered, though that can vary by state.