Health-care officials says immunity takes two weeks to develop after receiving a vaccination.
More than two-thirds of the state’s 73 known cases of mumps are in Champaign County, according to the Illinois Department of Public Health.
A local pediatrician is concerned about this week’s mumps outbreak in and around Columbia, Missouri.
Health officials in Boone County says seven suspected cases of mumps have been reported in the Columbia area.
Health officials say an outbreak of mumps among University of Illinois students could continue to grow.
The Illinois Department of Public Health says this year’s total is already the highest since 2008 when 91 cases were reported.
There have been 52 cases of the viral infection reported in Morgan and Sangamon counties so far this year.
Missouri is above the national average for the measles, mumps and rubella vaccine as well as Hepatitis B and Hepatitis A vaccines.