In a follow-up to the mumps outbreak in Illinois, state health officials now report 146 cases statewide, with 114 cases associated with the outbreak at the University of Illinois Urbana-Champaign.
Last week, Robert D. Palinkas, MD, Director of the McKinley Health Center at UI said the number of new cases daily varies between two and four. In addition, two large mass vaccination clinics were held last week where 4,599 people were vaccinated.
In 2014, Illinois reported 36 confirmed and 105 probable mumps cases. Nationally as of August 21, the CDC has reported 310 mumps cases, a number dramatically down from 2014 when 1,151 cases were seen.
Mumps is spread by droplets of saliva or mucus from the mouth, nose, or throat of an infected person, usually when the person coughs, sneezes or talks. Items used by an infected person, such as cups or softdrink cans, can also be contaminated with the virus, which may spread to others if those items are shared.
Symptoms typically appear 16-18 days after infection, but this period can range from 12-25 days after infection. It is usually a mild disease, but can occasionally cause serious complications.
The most common complication is inflammation of the testicles (orchitis) in males who have reached puberty; rarely does this lead to fertility problems.
Other rare complications include inflammation of the brain and/or tissue covering the brain and spinal cord (encephalitis/meningitis), inflammation of the ovaries (oophoritis) and/or breasts (mastitis) in females who have reached puberty and deafness. Anyone who is not immune from either previous mumps infection or from vaccination can get mumps.
The CDC says mumps can be prevented with MMR (measles-mumps-rubella) vaccine. MMR vaccine prevents most, but not all, cases of mumps and complications caused by the disease. Two doses of the vaccine are 88% (range: 66-95%) effective at preventing mumps; one dose is 78% (range: 49%−92%) effective.