Last year, around July, my SIL both got a cough that lasted for months. Neither one of us got it checked out, but it took a long time to go away. At the time, I looked up the symptoms of whooping cough and it seemed consistent with what we had going on, but I’m not positive what it was. It finally dissipated, but to this day I still occasionally get a slight rattle in my chest.
IIRC there was an article recently about how adults can harbor the disease and recommending a booster for the vaccine received soooooo long ago.