(Photo: AP)

SAN FRANCISCO, May 1 (Xinhua) -- San Francisco Mayor London Breed and Director of Health Grant Colfax on Friday announced coronavirus testing for all people at skilled nursing facilities (SNF).

The new directive will require all residents and staff working at the 21 SNFs in San Francisco to be tested for the coronavirus. The first round of complete SNF testing will start on Monday, May 4, and take approximately one month. Once all facilities have been tested, the goal is to establish a regular testing cycle about every two weeks, based on what is known about the virus' incubation period, according to the announcement.

"We've learned a lot during our ongoing response... Complete testing of staff and residents in all of San Francisco's skilled nursing facilities is the next step in our commitment to vulnerable populations and universal access to testing," said Breed.

"Our vision is to have universal access to testing for all in San Francisco. To get there, we have continually expanded testing, based on where the need is greatest, and the availability of resources," said Colfax.

All 21 SNFs in San Francisco served the city's most vulnerable populations including older adults and residents with underlying health conditions. Once introduced into a facility, COVID-19 can spread rapidly, and residents are at high risk of becoming seriously ill or even dying if they become sick. Early on, the city issued a health order restricting all non-essential visitors from SNFs in order to protect the residents and staff from exposure.

Although testing is a critical tool to find and confirm asymptomatic COVID-19 positive cases, it is just one piece of a larger strategy that also includes prevention, such as social distancing, frequent hand washing, appropriate use of personal protective equipment, and other recommended precautions, the announcement said.