Skip to content
Join our Newsletter

Your Good Health: Vaccines do not lower body’s resistance to other viruses

Innoculations help you prepare for the specific infections but do not weaken the immune system
web1_dr-keith-roach-with-bkg
Dr. Keith Roach

Dear Dr. Roach: A person who works in the medical field told me that she is against vaccinations. The reason she gave is that when you put a specific vaccine into your body, your resistance to any other virus or bacteria is severely diminished. Thus, if you get a COVID vaccination, you are then much more susceptible to the flu.

She says that your body naturally builds up resistance to whatever virus or bacteria is going around, and that resistance is reduced by the injection of particular vaccines. Is there any truth to this concept?

Anon.

No, the immune system is definitely able to fight off multiple infections or respond to multiple vaccines at once. The vaccine doesn’t reduce the body’s ability to fight off other infections.

The amount of antigens (specific parts of viruses or bacteria) in a vaccine is very small compared with what our bodies are exposed to every day through the environment. Both theoretical and observed results from clinical trials show that vaccines help you prepare for the specific infection the vaccine is protecting you from, but they do not weaken the immune system for other germs.

Had there been weakening of the body’s response to influenza (the flu), we would expect to see more flu infections, since over 80% of Americans and 91% of Canadians have had at least one COVID vaccine.

However, since the COVID pandemic we have had historically small numbers of flu infections. This was mostly due to mask-wearing and people not getting together as much as we used to before the pandemic, but this data does not support the idea that the COVID vaccine worsens susceptibility to the flu.

Dear Dr. Roach: I am a 70-year-old male in good physical shape, but I do have minor, annoying muscle aches and pains in both shoulders and my neck. I have done physical therapy for this, but it hasn’t really helped.

When I take two ibuprofen tablets, my aches and pains basically go away for the day, which is a godsend. Is it medically acceptable for me to take two ibuprofen tablets every day for the rest of my life?

T.S.

Ibuprofen and similar drugs (collectively known as NSAIDs) can be very helpful for many conditions. When used at high doses every day, they do have risks of side effects. But at the very low dose of 400 mg a day (the over-the-counter ibuprofen is 200 mg per tablet or capsule), the risks are small. Stomach upset is probably the most common, but there are still small risks of other issues.

Any medicine, whether it’s prescribed, over-the-counter or a supplement, has the risk of adverse effects. Physicians and other health professionals need to exercise their judgment in recommending them, making sure to weigh the risks and benefits.

Unless you have a medical condition that you haven’t told me about (history of bleeding ulcers from NSAIDs or severe kidney disease, for example), then the benefit (“godsend” is a pretty strong word) seems to greatly outweigh the small risks from such a modest dose of ibuprofen.

Dr. Roach regrets that he is unable to answer individual letters, but will incorporate them in the column whenever possible. Readers may email questions to ToYourGoodHealth@med.cornell.edu.