LAKE COUNTY, Ill. (WLS) -- Lake County health officials said there are two more possible mumps cases - one suspected, one probably - adding to the number of suspected, probable and confirmed cases of mumps in Lake and Cook counties.
Officials said there is one suspected case at Libertyville High School and one probably case at a school in Lake Zurich.
"I guess I'm just a little worried just because when one person gets it, easily anyone else could get it," said Kylie Kloser, Libertyville High School student.
With the addition of the two new cases above, the total number of possible and confirmed cases of mumps in Lake County stands at 33: 16 suspected, two confirmed and 3 probable cases at Barrington High School; five suspected cases at the Prairie campus of Barrington Middle School; one confirmed case in an adult in the town of Barrington; three suspected cases and one probable case at Station Middle School.
Barrington has the largest cluster of confirmed, probable and suspected cases in students and staff members: 31 of them.
"This is an uncommon increase for Lake County," said Victor Plotkin, epidemiologist, Lake County Public Health Department.
There is also one probable case at the mumps at a school in Arlington Heights in Cook County.
Mumps is a contagious disease caused by a virus. Symptoms include swollen glands along the jawline and in front of the ear. Other symptoms include headache, low-grade fever, fatigue and loss of appetite. Mumps is spread through coughing, sneezing and other contact with saliva.
After being exposed to the virus it can take two to three weeks for symptoms to arise and a person can be contagious a couple days before those symptoms develop.
Though students in Illinois are required to be vaccinated for mumps but there is an exemption for religious and medical reasons, and in recent years the number of unvaccinated students had risen.
"This cluster is another reminder of being vigilant towards infectious diseases and vaccine preventable diseases," Plotkin said.
Health officials say the vaccine is not 100 percent effective. In fact, most of these recent cases involved students who have been vaccinated. Still, the vaccine is considered the best way to prevent infection.
Lake County Health officials say in an average year they see two or three cases of mumps.
Schools affected have been undergoing deep cleaning. School officials encourage anyone showing symptoms to stay home. All unvaccinated students have been told to stay home as well.