Updated at 6:23 p.m.

Hidalgo County is seeing a “second wave” of confirmed mumps case that brings the total to 39, the county announced Tuesday, making this the largest community mumps outbreak in recent memory.

Some of those cases are related to the original outbreak last month and others are new, unrelated individual cases, said Hidalgo County Health and Human Services Director Eduardo “Eddie” Olivarez, who told The Monitor that because the cases are spread across the county, health officials are viewing the outbreak as a “county-wide problem.”

The county typically sees one to three mumps cases a year in infants, but cases of mumps in adults is rare, Olivarez said.

The original outbreak occurred early last month after a University of Texas Rio Grande Valley student tested positive for the virus. The outbreak was believed to be connected to two Mission gyms and limited to the McAllen, Edinburg and Pharr areas. Some of the latest cases, however, were reported in the Weslaco area.

County health officials fully expected the increase in confirmed cases because it can take 14 to 24 days for symptoms to appear after someone is exposed to the virus. Olivarez said Tuesday he also expects to see a “third wave” of cases later this month.

Mumps is a highly contagious virus that causes fever, muscle aches, headaches, appetite loss and swelling of the salivary glands in the jaw and neck area.

Hidalgo County’s mumps outbreak is in no way related to the increase of migrants passing through the Rio Grande Valley, Olivarez emphasized, adding that none of the 39 cases were affiliated with U.S. Customs and Border Protection personnel or anyone else who had come in contact with migrants.

Rather, he said, the increase is due in part to local schools and doctors “taking an aggressive stance” toward working to test for mumps following the initial case. As a result, people displaying mild symptoms are testing positive.

The recent Easter holiday also didn’t help, Olivarez added, because many people were traveling in and outside of the Valley.

There have been mumps outbreaks in other states, and the upcoming end of the school year will only increase the likelihood that students who could have been exposed to the virus in another part of Texas or the country could bring the virus here.

Anyone who suspects they may have mumps is encouraged to get tested by their local physician and to limit their contact with others. The county urges those with compromised immune systems to consult with a physician to determine whether a measles, mumps and rubella, or MMR, vaccine or booster is recommended.

Those who are not vaccinated are encouraged to get the MMR vaccine.

Mumps is not fatal and while there is no treatment, medication can alleviate the symptoms of the virus.

The nation is in the midst of its largest measles outbreak in more than two decades, and while no cases have been reported in Hidalgo County, they have been in other parts of the state.

“The mumps outbreak is helping us deal with detection, surveillance and isolation in the case we have a measles outbreak,” Olivarez said.

Hidalgo County has higher MMR vaccination rates than the national average which creates to herd immunity from the spread of contagious disease.