Merchant Services   Travelers frequently encounter insect borne diseases like malaria, dengue and tickborne encephalitis. Even though these diseases are not usually seen in the United States, West Nile Virus, transmitted by mosquitoes, can be a problem here. Middle East - The U.S. encourages Americans to listen to travel warnings noting Authorized Departure status and urging Americans to depart from the affected countries in the war. Colombia - Citizens of the U.S. and other countries have ...