When a child or adult walks into a hospital emergency room with a runny nose, cough, rash and fever, there could be several illnesses going on, and measles continues to be one of them, says Dr. Elizabeth “Betsy” Kleiner.

The infectious disease specialist works at Colorado Springs’ two major hospital systems — Penrose-St. Francis Health Services and UCHealth. She’s been called in as a team member on several recent measles cases to evaluate, assess and determine protocols.

The viral illness is “highly contagious,” Kleiner said. “The virus can remain floating in the air for several hours, even after the patient has left.”

People who have measles are usually contagious four to five days before and after a rash appears, she said, and 90% of people exposed will develop measles.

Patients suspected to have measles are immediately whisked to an isolation room in a hospital that “minimizes sharing of air space,” Kleiner said.

Patients are masked, as are staff, and a set of questions patients answer help medical providers figure out the health problem.

The hospital’s infection-prevention team and the El Paso County Department of Public Health are contacted to determine appropriate intervention and testing, the doctor noted. There also can be expedited lab tests to aid in diagnosis.

Thirty percent of measles patients can develop complications, such as diarrhea, pneumonia or swelling in the brain.

Fever lasting three to four days indicates potential complications, Kleiner said, and some people may need to be hospitalized.

But most don’t. Just 12% of the nation’s 1,168 measles cases so far this year required hospitalization, according to the Centers for Disease Control and Prevention. Three deaths have been confirmed.

As of Friday, Colorado has had 15 total measles cases this year, four of which have been traced to people in El Paso County, the Colorado Department of Public Health and Environment reports. The state announced a new case of a Boulder resident on Friday. A fully vaccinated adult recently traveled to Europe, where there are a large number of measles cases, the public health department said in a news release.

St. Francis Hospital saw its first case last weekend, when a child under age 5 entered the emergency room after traveling to Ontario, Canada.

The illness starts with a general feeling of being unwell and having cold-like symptoms. One to two days before a rash develops, oral lesions appear inside the mouth, opposite the cheeks and near molars, Kleiner said.

The rash appears on the forehead first, spreads down the body and can be accompanied by high fever.

The measles, mumps and rubella vaccine is 97% effective with a two-dose administration and 93% effective after the first round, Kleiner said.

“Vaccination is the cornerstone of prevention,” she said. “Breakthrough infections occur sometimes — we see those when people are exposed when there are high levels of outbreak.”

The child who sought care at St. Francis Hospital in Colorado Springs last weekend was vaccinated with one dose of the measles, mumps and rubella vaccine, according to the Colorado Department of Public Health and Environment.

For the most part, the decades-old vaccine is time-tested, proven to work and has minimal side effects, Kleiner said. Those can include soreness at the injection site, joint pain and a mild fever.

Fewer people getting vaccinated is the reason measles went from being considered eradicated in 2000 in the U.S. to today’s widespread outbreaks, according to the doctor.

The vaccination rate in Colorado fell to 88% for children entering kindergarten for the 2023-24 school year, which is far below the 95% threshold to maintain herd immunity, according to the CDC.

And the number of cases in 2025 is “far more than we’ve had in Colorado in all of the last decade,” Kleiner said.

El Paso County recorded six total cases between 2014 and 2024, compared with this year’s four cases to date, she noted.

Texas remains one of the epicenters for outbreaks. Around the country, many cases have emerged after people traveled to Mexico or Turkey, and of the infected, 95% were unvaccinated or their vaccination status was unknown.

More people have been asking for the vaccine in El Paso County this year, Kleiner said, although immunization statistics for the past six months are not yet available.