Read your coverage carefully. I flew to the UK for a 7 day trip on the Queen Mary 2 to New York. My trip insurance said it would cover quarantine costs, if I tested positive. What I didn't read closely, was the amount of the coverage. It was about %50 of the cruise cost. If I had tested positive in Southampton, it would cover my hotel costs. It was not enough to pay for hte last minute airline tickets to get back to the USA. (Luckily, we both tested negative. :-) )
Aloha,
John