Colorado health officials are closely watching the in the U.S. The state recently recommended that residents get vaccinated against the virus ahead of spring break travel.
Over 100 cases were reported in West Texas last month and the virus has now shown up in 11 other states, including Colorado's neighbor .
Colorado's state epidemiologist Dr. Rachel Herlihy does not take the prospect of a measles outbreak lightly.
"It's actually the most contagious virus that we know of," Herlihy said. "In a group of people that is not immune to the virus, 9 out of 10 people who come in contact with someone with measles will go on to develop a measles infection."
The Centers for Disease and Control documented 222 cases as of March 6. Herlihy says that when measles outbreaks reach this size they can take several months before they resolve.
Measles is more than just a rash. It's a serious respiratory disease that can have lasting effects. About 20% of people infected will need hospital care and it can be fatal.
What Herlihy is most concerned about are the pockets of under-vaccination that exist throughout the state.
"Individual schools or childcare facilities, playgroups, church groups or community organizations where vaccination rates in those much smaller groups are well below the threshold of protection," she said.
Colorado's health department keeps across the state. Front Range school districts are all above 90%, but some districts - including Lake County and several in and around Colorado Springs - fall in the low to mid 80% range.
Some residents may be wondering if they or their children have been vaccinated. You can request a copy of vaccine records through the Colorado Public Health and Environment . Officials also recommend talking with your primary health provider.
Dr. Herlihy can't say for sure if Colorado will see measles cases in the future but is using the current moment as a reminder of the risk.
"We're really seeing these outbreaks occurring elsewhere as a call to action for all of us in Colorado to make sure that we are protected," she said.
