"Vaccines are not just given to prevent disease," Edwards said. "Individuals who are vaccinated, typically, if they get sick their disease is much less severe and in some cases the ability for them to communicate the disease is decreased."
Two vaccines, which cover measles, mumps and rubella, are typically administered to children under the age of 7: one between 12 and 15 months of age and another between the ages of 4 and 6, Edwards said.
Even with the two recommended doses, the CDC reports the vaccine is only 88 percent effective against infection. It is slightly more effective for measles: 97 percent if an individual receives both doses, according to the CDC.
Earlier this month, county health officials announced the first confirmed case of measles in the area since 2011. That child had traveled abroad and received "age appropriate vaccinations."
Officials said at the time they were notifying more than 200 potential contacts with the child across Salt Lake, Utah and Davis counties. Since then, one individual who was in contact with the child has contracted measles.
Symptoms of both mumps and measles include high fever. But measles also is characterized by a cough, runny nose and rash that spreads over the body, according to the CDC, and mumps, by muscle fatigue, headache and swollen salivary glands.
Edwards said an informational letter has been sent to parents at the Salt Lake County school where the two infected children attend, but he declined to identify the school.
There have been increased outbreaks of measles across the country, Edwards said.
The CDC reported that 27 states reported 495 mumps infections in January 2017, compared to 229 mumps infections in all of 2012.
Edwards said that spike is also a subject of investigation nationally, including whether it reflects mutation of the mumps virus. Members of the public, meanwhile, are being encouraged to make sure their vaccinations are up to date.
County health officials also urge resident who think they may be infected with mumps or measles to contact their local health department.
They should not, however, visit a doctor's office, hospital emergency room or clinics without notifying the facility by phone first, to allow for precautions against exposing others.