MARIN COUNTY, CA — Four additional cases of the new coronavirus were reported Tuesday in Marin County, the same day a shelter-in-place order went into effect in an attempt to slow the spread of COVID-19. The shelter-in-place order will last until at least April 7.

The new cases bring the county's total to 15. All but three of the cases were detected in the county's field testing site, where health officials have performed nearly 200 tests, according to Dr. Matt Willis, the county's public health officer. On Wednesday, the county is adding private laboratory Quest Diagnostics to the team to support the public health response.

"This will increase our capacity to test, although testing still remains limited to people with symptoms of COVID-19 who've been referred by their doctor," Willis said. "This is an example of the kind of public-private partnership that we're going to need to battle this pandemic."