Officials in the state of the west coast will sound the alarm after the traveler diagnosed with a highly contagious viral disease

Public health officials in the state of Washington warn residents that a Canadian traveler who was contagious with measles visited several public locations, including the Seattle-Tacoma International Airport.

The person, whose vaccination status is unknown, traveled through the Seattle-Tacoma International Airport and visited multiple public locations in Renton, Bellevue, Seattle, Everett and Woodinville between April 30 and May 3, according to a King County press release.

Health officials said the Canadian received the diagnosis after traveling through the area.

People can get infected with measles for days without seeing an eruption. (Istock)

Measles vaccines given a long time could be less effective now, doctors say.

The spread of measles can occur before any eruption appears, and the virus can remain in the air up to two hours after someone contagious with measles leaves the area.

The authorities said that the possible exhibition sites where the Canadian tour traveled include the Seattle-Tacoma International Airport; Bellevue Market Place at the Factoria shopping center; Chateau Ste. Michelle Winery; Home Depot on Redmond; Lumber Dunn in Renton; Genki Sushi in Renton; Topgolf Renton Sport Bar And Restaurant; Pho Mignon in Kirkland; Kobo in fig art gallery; Asian market Uwajimaya Seattle; Stoup brewing; Sichuan’s spicy style; a hotel; and three fitness centers.

A person diagnosed with measles from Canada visited multiple public locations in the state of Washington, while contagious. (Reuters/Chris Helgren)

What you need to know about measles outbreak

While the case is not connected to any previous case of local measles, public-seattle health and King County responded to two other measles cases this year of non-residents.

This year there have been a total of five measles cases in the residents of the Washington state.

Meagan Kay, a medical epidemiologist of Public Health – Seattle and King County, said there is a “significant resurgence of measles” in the United States already worldwide.

Measles vaccines are highly effective in preventing disease. (Raquel Natalicchio/Houston Chronicle through Getty Images)

The fear of measles at the Mayor Airport: what to know about potential exposure

“With more than 1,000 cases reported so far this year, 2025 is on the way to having the largest number of measles cases in the United States since the early 1990s,” Kay said. “It is an important moment to verify your vaccination status and vaccinate if you are not protected.”

Click here to get the News application

The officials encouraged those who were in the potentially affected places to find out if they are vaccinated for measles and call a medical care provider immediately if they develop a disease with a fever or with an inexplicable eruption.