You can check each cruise line's travel insurance requirements here:
Carnival
link opens in a new window operated by external parties and may not conform to the same accessibility policies as JetBlue
Royal Caribbean
link opens in a new window operated by external parties and may not conform to the same accessibility policies as JetBlue
Celebrity Cruises
link opens in a new window operated by external parties and may not conform to the same accessibility policies as JetBlue
If you need or would like to purchase travel insurance for your flight + cruise package, you can do so here.