Here are some resources for finding out about many diseases. Some pages are already translated:

Medline Plus: http://www.nlm.nih.gov/medlineplus/languages/all_healthtopics.html

Refugee Health Information Network: http://rhin.org/EmergingPopulations.aspx?PopulationID=10

For Service Providers:

This website has information on different cultures, care topics and information for your clients in their languages: http://ethnomed.org/culture