Resources you are likely to need for your trip:
U. S. State Department – International Travel
Center for Disease Control – Travelers’ Health
Travel Protection – We recommend that you consider purchasing a travel protection plan to help protect you and your travel investment against the unexpected. Travel protection plans include coverage for Trip Cancellation, Trip Interruption, Emergency Medical and Emergency Evacuation/Repatriation, Trip Delay, Baggage Delay and more.
We do not recommend any particular travel protection company.
Here are some links to help you find a company that suits you:
Consumer Reports contains helpful advice about travel insurance.
Travel Insurance Review is an extensive site devoted to the topic. The page about Retreats explains why you might need such insurance: http://www.travelinsurancereview.net/2012/10/22/retreat-travel-insurance/