yellow fever
 

About 6 years ago, I went on a trip to Uganda and had " all the shots"' I was given a card that said I had yellow fever shots for immigration, though I do not recall if anyone looked at it.I still carry it with my passport for international travel, though no one has ever asked for it. Do I still need to carry it?

Only if you are traveling to/from regions in which yellow fever is endemic (or countries which require all travelers provide proof of vaccination upon entry).

Some countries which do not currently have yellow fever but which have the right conditions for it will require proof of vaccination if you've recently been to areas with yellow fever.

There is a lot of info from the US CDC which may help.

Of course, enforcement of the vaccination requirement is a joke in many countries. I've landed at one country in particular where I witnessed a vaccination booklet used by one passenger passed back to other passengers for reuse at the airport upon arrival.

Yeah, it's still required in some countries. My folks had to get a new book since they lost their old ones when they traveled to Brazil a few weeks ago.

I've been to Brasil over 50 times in the last 11 years. I've never had a yellow fever vaccination, and no one there has ever asked for proof of one.