Health officials in Washington are tracking a mumps outbreak that has affected 80 people so far near Spokane, the Spokane Regional Health District reported.

Of the 80 reports, 50 of the patients reported having been vaccinated for mumps. Health officials in Spokane are expecting the number of cases to spread in the coming days. 

The infection has particularly affected children, as 58 of the 80 cases involved young people aged 19 and under. 

According to Spokane Regional Health District, mumps is a contagious viral infection that can cause painful swelling of the salivary glands, especially the between the ear and the jaw. Some people with mumps won't have gland swelling. They may feel like they have a bad cold or the flu instead.

Mumps lasts up to 10 days, but it can cause complications that affect the brain, the testicles, the ovaries or the pancreas, Spokane Regional Health says.

Symptoms usually appear two weeks after exposure. While the typical treatment for mumps is rest, hospital stays are some times required in severe cases.