Childhood immunizations in the United States
Mumps is a contagious disease caused by the virus by the same name. Since most people in the United States have been vaccinated, mumps is now a rare disease in this country. Currently there are no specific treatments for mumps.
Mumps is spread person to person by droplets of saliva or mucus from the mouth, nose or throat of an infected person. This is done through coughing, sneezing, talking, and coming into contact with contaminate items. Transmission likely occurs before the salivary glands swell an up to 5 days after the swelling begins.
Impacts of tourism
Examples of invasive species spread by tourism:
-Bigheaded ant (Pheidole megacephala): Is one of the worst invasives and classified under the “worlds 100 worst” invasive species. Originally found in the Galapagos islands in 2007 within ship cargo for tourist supplies. Ants can be spread with the movement of people from one island to another. 
-Cheatgrass (Bromus tectorum): Spread fast, don’t allow native species to grow, can cause forest fires to spread rapidly. Can be carried by people through shoes and gear, pets and other animals can spread the seeds through their travel as well. 
-Zebra Mussels (Dreissena polymorpha): These are believed to have come from the Caspian Sea in Europe in a ships ballast water. They are spread by uncleansed boats from one body of water to another as tourists move to different locations.