PORTLAND, Ore. (AP) — Vice President Mike Pence is trying to reassure Americans that the federal government is working to make sure state and local authorities are able to test for coronavirus in the communities.

Pence’s assurances come as the number of U.S. cases has grown with new infections in Illinois, Rhode Island and Washington state. Research in Washington state, home of the first diagnosed case in the U.S., suggests the coronavirus may have been circulating undetected in that state for weeks.

The research was not published in a scientific journal or reviewed by other scientists. Two more people were diagnosed near Seattle on Sunday, while 50 people at a nursing facility are sick and being tested.