Mumps is an infectious disease caused by a virus. It is primarily spread by droplets during coughing and sneezing as well as by direct contact with the saliva of an infected person.
Symptoms of mumps typically appear 16 to 18 days after exposure. A person is most infectious from two days before symptoms appear to five days after. Almost half (40%) of those infected with mumps develop facial swelling (parotitis) on either one or both sides of the face. Some people with mumps have only respiratory symptoms and may not know they have the infection.
Two doses of mumps-containing vaccine are required to be fully immunized against mumps. Due to historical changes in Ontario’s vaccine programs, individuals born between approximately 1970 and 1992 likely received only one dose of MMR vaccine and would not have acquired natural immunity through infection.
To obtain or inquire about an immunization record for yourself or your child, please contact your local public health unit
Counts and rates of mumps cases in Ontario:
2007 – 2017
Note to clinicians
There was an increase in mumps cases in Ontario in 2017, and increased mumps activity continues to occur in many parts of North America. Anyone born after 1970 should be appropriately immunized with two doses of measles, mumps and rubella (MMR) vaccine. Many in this age group will have only received one dose in the past.
If a patient’s immunization record is unavailable, immunization with mumps-containing vaccine is preferred, rather than ordering serology to determine immune status. This avoids the potential for false positive results, reduces the risk of missed opportunities for immunization and is consistent with advice in the Canadian Immunization Guide.
Please note this does not apply to specific occupational groups such as healthcare workers who require either documentation of immunization or serologic proof of immunity.