UW Medicine ramps up measles testing as nationwide outbreak grows
SEATTLE – Measles testing is ramping up at UW Medicine as the Puget Sound area gets ready to welcome a flood of out-of-state visitors this summer, potentially coinciding with a nationwide outbreak fueled by a virus known to spread largely through air travel.
Dr. Alex Greninger is excited that Seattle will be one of 16 cities that will host this year’s FIFA Men’s World Cup. He’s looking forward to sharing the region with hundreds of thousands more people. But the infectious disease doctor also knows the games — combined with cruise season and a general uptick in summer travel to the Pacific Northwest — means more measles cases could be on their way.
UW Medicine has to activate,” Greninger said during a Wednesday news briefing. “Typically, the virology lab would not be doing measles testing. We would send this to the state lab.”
The machine, called a Panther Fusion instrument, that will soon boost testing sits in the corner of one of Harborview Medical Center’s research buildings on First Hill. But in the next month or so, it will move to Renton, the site of UW Medicine’s new virology lab.
The Panther instrument can scan up to a thousand specimens over eight hours and test samples for up to 20 viruses, including influenza, SARS-CoV-2 and now measles, said Erin Goecker, health services manager at UW Medicine’s retrovirology lab.
“We have to be ready,” said Greninger, head of UW Medicine’s Division of Infectious Disease Diagnostics in Laboratory Medicine and Pathology.
In the first two months of 2026, Washington state saw 26 measles cases, more than twice last year’s total count. Two counties, Snohomish and Clark, are battling clusters of infections that so far have remained fairly small and are almost all among people who are not vaccinated against the disease. There are two cases in which vaccination status is unknown, according to the state Department of Health.
The nationwide outbreak is now centered in South Carolina, and has led to thousands of measles cases and three deaths over the last year.
About three-quarters of the country’s cases have been among children, said Dr. Shireesha Dhanireddy, UW Medicine’s associate chief medical officer. As of last week, more than 1,200 infections had been confirmed in 31 states this year, according to the Centers for Disease Control and Prevention. Just four cases were reported among international visitors.
As more hospitals and public health systems throughout the U.S. gear up to respond, Dhanireddy said the key to quashing the spread is to quickly identify people who might be infected and properly isolate them.
Reliable testing is also part of a successful response, she and Greninger said.
The state Department of Health’s laboratory in Shoreline runs nearly all measles PCR tests in Washington and is the only one that performs whole genome sequencing for these cases, which is done to analyze the virus’s genetic makeup and better understand how cases here are related to each other and to ones elsewhere, DOH spokesperson Mark Johnson said.
From the time a specimen arrives at the lab, the state’s typical turnaround time for measles PCR testing is one day, Johnson said. In January and February, the state lab tested at least 81 samples — compared with nine during that time frame in 2025.
As of this week, the state public health lab has not experienced delays as the demand for measles testing has increased, Johnson added.
The state does a “fantastic job” testing for various viruses, Greninger said. But because approval from state and local health departments is required before a measles test is sent to the DOH lab, there’s room to help speed up the process and add testing capacity.
“We did this during COVID. We’ve done this during mpox,” he said. “It just used to be that there were so few (measles) cases and so few tests that it didn’t make sense. But that’s not today.”
Measles spreads through the air, and symptoms include a fever, cough, runny nose and rash, though a person can be contagious several days before the rash appears, Dhanireddy said. In the longer term, the disease can cause inflammation in the brain and lungs.
The best way to protect against severe illness is through vaccination, she said.
Symptoms begin seven to 21 days after exposure. If you think you might have been exposed, or have symptoms, call ahead to a health provider; do not just walk in, as you could expose many others to the illness.
UW Medicine has five total Panther machines, the first of which arrived in March 2020 to help the hospital system respond to the pandemic.
“We did not have those prior to COVID,” Greninger said. “Now we have them. And we can use them for other things.