Oh man
I've only had one guy call in sick mid trip.
We were on a layover in Frankfurt a few years ago. There was me, the other FO and the captain, and three pilots from the other crew. We all went to a restaraunt, had a few different variations of the same dish (Schnitzel!) and drank a few rounds of beer.
The next morning, about 0600 the phone rings and I'm thinking it's the hotel or the station manager calling to say that the flight has been delayed. International, they ALWAYS call you at the hotel to notify you of flight delays.
Well, it's the other FO and he can't find the captain. I'm like "WTF? What' sup?"
Apparently, something hit him about 0300, he left a "path of fecal destruction" from his bed to the toilet, had to go back several times, didn't always make it and housekeeping had been to his room twice already.
And it's only 0600.
I call the captains room, no answer, call the front desk to connect me, no dice. So I guess that he's out taking a run in the park so I bust out that international medical card and call a doctor over to the hotel. Call the front desk to coordinate, throw some clothes on, venture down to the FO's room and OMG, I thought he was going to die.
Curled up in the fetal position, the room smells like the geriatric unit at a convalescent home and he says, "call... call a doctor"
"already one on the way, buddy, hang tight!"
He looked like HELL and part of me wanted to start digging through his belongings to look for a number to call his next of kin. He looked THAT bad.
Anyway, the doctor arrives, takes care of him and eventually, the captain and I fly "two man" from Frankfurt to Porland, ME, filed at .83, leaving him behind in the hotel with the doctor a few hours later.
I can't tell you how paranoid I was that whatever he had was going to hit myself or the captain over the Atlantic.