JOHNSON COUNTY, TX (KTRK) -- A once-dormant contagious disease has sprouted up in a North Texas town, causing a school district to issue a health warning.At least 10 cases of mumps have been confirmed by health authorities in Johnson County.Of the cases, seven involve students within Keene ISD."I think the parents have to be very careful," said Marisol Villalobos, a parent.Parents like Villalobas want to know what the district and county health department are doing about mumps.Doctors think the outbreak originated from a family who traveled to Arkansas over the Thanksgiving holiday."My kids have already the immunization and I think that will cover," said Villalobos.Not every parent within the district feels the shots are necessary."You definitely don't want seven or 10 cases to turn into 40 and that can easily happen," said Ricky Stephens, the superintendent for Keene ISD.Stephens said the 34 students, who are not vaccinated or are under-vaccinated, will not be able to attend school for the next 26 days."You can't just do one campus and assume you're safe," said Stephens.Lake week, Dallas County issued a health advisory regarding one confirmed case with the possibility of several others."Mumps is almost unheard of in this day in age," said Dr. Elvin Adams with the Johnson County Health Department.Dr. Adams said patients usually feel tired and weak. Then a fever is possible and that is when the glands in a person start swelling."So you look like a chipmunk that has a mouthful of nuts," said Dr. Adams.While Dr. Adams said it is not considered a lethal disease, it can be painful and easily spread if nothing is done.The state health department plans to be on Keene ISD property on Thursday to give out vaccines to students who need shots. KTVT reports that any students who choose not to get vaccinated, must wait the 26 days because the disease can incubate for 25 days.