Jack nodded and lay down again. He coughed a bit. He was feeling rather miserable. He shivered and coughed more.
The Doctor didn't like the idea of what the Master could be up to. He needed Jack to be feeling well as he didn't want him left behind. He looked at Rose, He could tell that she too was trying to figure out what the Master was up to.
He didn't want anybody hurt and he was worried.