Rubulavirus
If not vaccinated against mumps, susceptible individuals catch the disease by breathing around an infected person who has coughed or sneezed, releasing their contaminated saliva. Those who have had mumps are usually immune to future infections of the disease. Children have the highest risk of catching mumps, and it is rare for an adult to contract mumps. The incubation period for mumps can range from a couple weeks to a month, while the illness period is a few weeks. The swelling of the salivary glands is caused when the virus travels from the respiratory tract to the salivary glands and multiplies within the glands, causing the glands to swell.
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.