(The Hill) Montana public health officials have found five cases of measles in Gallatin County, the first cases of the disease in the Treasure State in more than three decades.  

Gallatin County is home to the state’s fourth most populated city Bozeman and is the second most populated county in the state.   

A handful of children and adults contracted the disease while traveling outside of Montana, according to the state’s Department of Public Health and Human Services (DPHH).  All of the children and adults are isolating at home and are either unvaccinated or their measles vaccine status is unknown, according to officials.

“While it is unfortunate to have cases of measles after 35 years of disease inactivity in Montana, we have been working diligently with our local partners to prepare,” DPHHS Public Health Physicians Maggie Cook-Shimanek said in a statement.

“We are confident that our public health and clinical partners will work together and address this situation as quickly as possible,” she added.

State health officials noted that there are two locations where residents could have potentially been exposed to the virus: North Coast Electric at 7401 Shedhorn Dr, in Bozeman, Mt., between 7:30-10:30 a.m., and Interwest Tire at 6460 Jackrabbit Lane in Belgrade, Mt., between noon and 4pm on April 14.  

Measles is an extremely infectious disease that is airborne. The virus can remain in the air and on infected surfaces for up to two hours. One person infected with the virus can infect nine out of 10 people around them if they are unvaccinated, according to the World Health Organization.

A measles outbreak in West Texas was detected in late January and has since spread to neighboring states.   

Over 700 measles cases have been reported in the U.S. this year, with 561 confirmed cases of the virus in Texas alone, according to the most recent statistics from the Centers for Disease Control and Prevention (CDC).  

About 70 percent of people who have been infected this year are children and teens, and 97 percent of those who have contracted the disease are unvaccinated, according to the CDC.  

Two children have died amid the outbreak this year and a third death is currently under investigation.  

Rising measles cases have put pressure on the Department of Health and Human Services Secretary Robert F. Kennedy Jr, a longtime critic of vaccines, to mitigate outbreaks of the virus.

After backlash from public health experts over his initial response to the Texas outbreak, Kennedy has said the measles, mumps and rubella (MMR) vaccine is the “most effective way to prevent the spread” of the virus.