An unexpected side effect from some COVID-19 vaccines

According to several reports and one major study, both the Pfizer and Moderna vaccines can cause lymph nodes to swell, especially those in the armpit on the side where the shot was given.

And any armpit lymph node swelling will immediately cause concern in most women because that may be a sign of breast cancer (cancers often invade the local lymph nodes).

So, just take that into account if you’re female and you get a Pfizer or Moderna vaccine: The lymph node swelling you may get is merely a sign of active involvement of your immune system.

And that’s a good thing.