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.
Endocardial fibroelastosis
Noren and colleagues at University of Minnesota, acting on an idea floated at a pediatric meeting, were able to show a relation between exposure to maternal mumps in fetal life, EFE, and a positive skin test for mumps in infants. This brought on a large ongoing controversy and finally prompted a virologist colleague of theirs to inject embryonated eggs with mumps virus. The chicks at first showed the changes of myocarditis, about a year later, typical EFE, and transitional changes in between. Despite this, the controversy about the role of mumps continued as the actual incidence of EFE plummeted. The proponents of mumps as a cause pointed to this as the effect of the recent implementation of widespread mumps immunization.