Antibodies do not equal immunity

Dear Dr. Roach: I am a female and 66 years of age. I had a varicella zoster blood test a couple of years ago to see if I had ever had chickenpox, because I had concerns about getting the shingles shot. (I had my first-ever flu shot quite a few years ago, and am convinced that I reacted badly, coming down with a severe case of the flu within a couple hours of the shot.) I know that it is said that you do not get the flu from the flu shot, but this reaction made me question getting the shingles shot.

My blood test showed that my antibodies (IGG) are 2,279. My dermatologist called me with the results and said: “Yes! You definitely had the chickenpox, big time.” I understand the normal count of antibodies is between 135 to 165. He actually questioned whether I have enough protection that I might not need the shingles shot. But he said he wasn’t sure how to weigh in on this one. He suggested I call the Centers for Disease Control and Prevention, but I thought I’d ask you. — D.T.

I wouldn’t test a person in your situation for antibody levels. Whether or not you were exposed to chickenpox, I still would recommend a shingles vaccine, which is what the current guidelines recommend.

However, now that you have the result, it isn’t clear from the CDC guidelines what you should do. My recommendation is that you still get the vaccine.

The injectable flu vaccine contains no live flu virus. It isn’t possible to get flu from a shot. Some people do get a reaction of low-grade fever and muscle aches, which rarely lasts more than a day or two: That’s the most likely explanation in your case. Of course, you may have had very bad timing and were coming down with the flu right when you got the shot, but the timing makes me doubt that degree of coincidence. Nonetheless, flu shots save lives.

Write to Dr. Roach at ToYourGoodHealth @med.cornell.edu.