Pennsylvania is one of two states that have had at least 300 confirmed or likely mumps cases so far this year, according to the U.S. Centers for Disease Control & Prevention.

The other is Texas.

Moravian College in Northampton and Lehigh counties is in the midst of an outbreak, with nine confirmed and six probable cases, according to the Pennsylvania Department of Health, which reported in late March that there were 99 cases in an outbreak at Temple University in Philadelphia.

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In the spring of 2017 there were at least 86 cases in an outbreak at Penn State University's main campus in State College.

According to the state department of health, there have been 143 confirmed and 232 probable mumps cases in the state so far this year, and Lancaster County was below the threshold (five confirmed or probable cases) for it to provide a county-specific number.

Health officials say there's no specific treatment for mumps and most people recover completely in a few weeks, but that in some cases it can cause serious complications including deafness or inflammation of the brain.

Penn State University's mumps outbreak up to 86 cases

According to the CDC, mumps cases decreased by about 99% after vaccination for it started in 1967, with two-dose childhood vaccination proving about 88% effective against mumps. In colleges and other close-knit communities suffering outbreaks, it may recommend a third dose of the vaccine.

CDC mumps cases 2000 through September 2019