The continuing immunity to the flu probably is a proxy for a whole bunch of other immune system characteristics that contributed greatly to the fact that these individuals lived into their 90’s and 100’s.
Since, I’ve read, about up to 75% of people in their late 70’s have some type of cancer (whether or not it becomes a manifest disease process for them), folks that live into their 90’s and 100’s also apparently have “immunity” to cancer, heart disease and stroke as well.
You used to hear the description, “Grandma has a strong constitution.” That is likely a statement of biological as well as genetic fact.
But still producing antibodies 90 years later-—WOW!
My Father recently died at age 90. Interestingly he had heart problems nearly all his life. I once heard Jack Benny say the secret to a long life was to get a disease and take care of it.
I often wonder if these instances we hear of of people getting diagnosed with cancers at young-ish ages isn't something new at all but something that always happened and without the technology and screening processes we just never knew that people often had and lived long periods of time with these slower growing cancers.
You may be right. I come from a long line of survivors, almost all living into their nineties. The most frail was my grandmother who got breast cancer (but lived 30 more years) and had a massive heart attack (but lived another fifteen years beyond that). She died at age 93 right shortly after 9/11. That is the only cancer of which I am aware in both sides of the family. My dad is turning 80 years old tomorrow. My mom is a year behind him. Of their combined eight siblings, only one has passed on from a heart ailment. Maybe I just lucked out with good, hearty genes. Since I was born, I’ve been hospitalized only three times—each time for childbirth. I’ve not treated myself as well as I should but surely something is helping to sustain me.