You can NOT jumpseat home on the company if you are sick in the field. The company is supposed to buy you a ticket home. I had this happen to me. I talked to the DO about jumpseating home when I was sick on a trip. He said it was OK. I then called CP Jeff K and he said no. He said the company didn't want to have the crew have to worry about evacuating a guy off the jet in an emergency. I know, there are lots of scenarios of why being sick wouldn't be a hinderance to the crew. He said the company will buy you a ticket back. They bought me a ticket. I called the CP because I knew a guy that got in deep s%$# for jumpseating sick. The company's issue was if he was ok to jumpseat, why wasn't he ok to fly? Just sayin' what I heard.