It is flu shot season and my goal each year is to give more influenza vaccines in my clinic than any of the other pulmonologists. So, I offer it to all of my patients and continue to be amazed at how many of them decline because “Every time I get a flu shot, I end up getting the flu”. There is no live virus in a flu shot so you are just as likely to get the flu from a flu shot as you are likely to get pregnant by taking a birth control pill.
So why are patients so sure that they’ll get an infection from the flu shot. There are two main reasons. First, they may have had some muscle pain at the injection site or even some mild myalgia after a previous injection – this is a reaction to the vaccine and not an infection. If anything, it means that the vaccine is working because your immune system is mounting a response to it.
The other reason patients think that they get the flu from a flu shot is from superstition. The average American gets 2-4 upper respiratory infections (“colds”) per year. Lets just say it averages out to 3 colds per year. That works out to 1 cold every 17 weeks. In other words, statistically, 1 out of 17 patients will get a cold within a week of getting a flu shot purely by chance. Because they associate that cold with the flu shot, they incorrectly deduce that the vaccine caused the cold (which they equate to the flu). By the same argument, 1 out of 17 patients will get a cold within a week of Easter but you don’t hear patients telling you that they got the flu from the Easter bunny.
As it happens, if it wasn’t for influenza, I never would have been born. My grandmother’s first husband was one of the 21 million people who died of the “Spanish” influenza epidemic of 1918-1919. She then remarried to my grandfather so if her first husband hadn’t died of the flu, I wouldn’t be writing this post now. In the United States, about 23,000 people die of influenza each year; some years more and some years fewer, depending on the specific strains that go around that year.
It is particularly important for all healthcare workers to get vaccinated so that they don’t become a vector to transmit influenza to vulnerable patients. A few years ago, I admitted one of my patients with pulmonary fibrosis to the hospital with worsened shortness of breath. On admission, I did a bronchoscopy and sent PCR testing for influenza – it was negative. We determined that he was in heart failure and he improved over the days with diuresis. He lived alone and had no relatives so during his hospital stay, he had no visitors. After about a week, he became suddenly worse with hypoxemia and high fever. I repeated the bronchoscopy and this time, his influenza PCR was positive for influenza A. Based on the incubation period, he had to have acquired his influenza in the hospital. Since he didn’t have any visitors, he had to have acquired it from one of the doctors, nurses, or therapists. He never made it out of the hospital and died of his influenza in our ICU.
So, I’m pretty passionate about getting everyone who works in the hospital vaccinated for influenza each year. I don’t care so much whether they get influenza but I don’t want them transmitting it to a patient who would be more likely to die from it.
October 12, 2016