State epidemiologist warns of national measles surge; Pitkin County urged to confirm records and consider targeted vaccination

Lauren Duvall, field epidemiologist at the Colorado Department of Public Health and Environment assigned to Pitkin County, told the Pitkin County Board of Health on April 17 that the United States is experiencing an unusually large measles season and that most cases to date involve unvaccinated people.

The state is tracking hundreds of U.S. cases and Colorado has investigated three individual cases so far, Duvall said. "This is an unprecedented amount of cases in The United States," she said, and noted that "97 percent of these cases are in either unvaccinated or unknown immunization status." She urged clinicians to call public health immediately for suspect cases and to prioritize testing through the state public health laboratory.

Why it matters: measles is highly contagious and can cause severe complications. Duvall emphasized that timely public-health action — including rapid assessment of susceptibility and, where appropriate, post‑exposure prophylaxis — can prevent secondary cases and reduce severe outcomes.

State and local role: Duvall described how Colorado evaluates suspect patients on three factors — clinical compatibility (fever, rash and cough/runny nose/conjunctivitis), susceptibility (no record of immunity or prior infection), and exposure within the previous 21 days. For people without immunity, the state can offer two interventions: an MMR vaccine within 72 hours of exposure (which may prevent or modify disease) or immune globulin (IG) within six days for those who cannot be vaccinated. "Administration of vaccine to contacts who don't have any immunity to measles may abort infection or modify disease if it's given within 72 hours of their first exposure," Duvall said.

Local instances: Colorado reported three cases reviewed by Duvall. The first (a Pueblo resident) had traveled to Mexico and was reported late, outside the post‑exposure window; no secondary cases were identified. The second involved an unvaccinated infant who had traveled to Mexico; health officials evaluated more than 120 contacts at a Denver emergency department and provided MMR or IG to many contacts, with monitoring of the remainder. The third case involved an Archuleta County resident who had been at Wolf Creek Ski Area while infectious; investigators have evaluated more than 400 contacts and continue to monitor a small number of unvaccinated contacts.

Testing and reporting: Duvall asked that providers notify the local public health agency or CDPHE immediately for suspected measles and to send specimens to the CDPHE public health laboratory rather than commercial labs when possible. She said the state lab can prioritize testing and often return results in about 24 hours.

Vaccination guidance and communications: Duvall said Colorado is monitoring other states' responses; Texas has implemented earlier vaccination recommendations in response to an outbreak there. Colorado is evaluating whether to recommend MMR at younger ages (as early as 6 months) in some settings, but such a change affects insurance and billing and would be communicated via statewide health alerts and press releases. She also noted CDPHE publishes annual county MMR coverage data and that the state has seen an increase in MMR uptake recently.

Duvall closed by giving contact information and asking local providers to call CDPHE for guidance on patient evaluation, testing and post‑exposure measures. "We are widely available to take calls and assist," she said.

Looking ahead: Pitkin County Public Health and CDPHE said they will continue coordinating contact investigations and considering targeted vaccination clinics in areas with identified exposures.