ARUP Launches Molecular Measles Assay To Support Public Health Response to Recent Outbreaks

ARUP Laboratories is the first reference laboratory to offer a molecular measles test that both detects the measles virus and distinguishes between infection-causing and vaccine strains of the virus. This assay, Measles Virus by Qualitative NAAT, will provide essential information for appropriate patient management and aid public health efforts to limit the spread of infection.

"Our assay contains two different targets: one to detect all measles viruses, and one that is specific for the vaccine strain of measles virus," said Benjamin Bradley, MD, PhD, medical director of the Institute for Research and Innovation in Infectious Disease Genomic Technologies, High Consequence Pathogen Response, Virology, and Molecular Infectious Diseases.

The measles, mumps, and rubella (MMR) vaccine uses an attenuated form of the measles virus that is still live and able to replicate. As a result, approximately 5% of individuals who receive the vaccine may develop a measles-like rash that can be mistaken for active infection. Although it's possible for vaccinated individuals to develop a rash, the vaccine virus is not transmissible in these cases, Bradley said.

"The ability to distinguish between infection and a vaccine-induced rash at the time of diagnosis will be important for physicians to appropriately treat patients and mitigate the risk of spread," Bradley said.

Measles is an acute viral respiratory illness that is highly contagious. As of April 11, 2025, the CDC had reported 712 confirmed measles cases so far this year. Seventy-nine of those cases required hospitalization, comprising 11% of the total case count, and two deaths have been confirmed.

"If you have an infected person who sits in a room with 10 unvaccinated individuals, nine of those 10 people would walk away and then develop measles virus infection," Bradley said. "This transmissibility requires a high level of vaccination coverage. We see the biggest impact in communities with low adoption of the vaccine."

The high transmissibility of the measles virus also heightens the need for fast and reliable testing to better inform clinicians and public health officials in their efforts to manage outbreaks. ARUP will perform this assay on a fully automated platform that will streamline the testing process and yield results more quickly, providing answers to clinicians and patients sooner. Results from ARUP's molecular measles assay will be reported within one to three days.

"ARUP has the expertise and the capability to address these reemerging pathogens, and we are committed to doing what is right for the patient and supporting providers as they respond to these outbreaks," Bradley said.

More information about ARUP's testing for measles is available here.

Kellie Carrigan, kellie.carrigan@aruplab.com