Following an increase of confirmed COVID-19 cases over the past month, Bay Area public health leaders are now asking residents to cover their faces with a cloth before leaving their homes, heeding advice released by the state on Wednesday.
The counties, including Santa Clara and San Mateo counties, are taking up the California Department of Public Health's new guidance on face coverings, which states that "there may be a benefit to reducing asymptomatic transmission and reinforcing physical distancing from the use of face coverings."
However, the department's guidelines emphasize that masks are not a replacement for strong defenses such as physical distancing and hand washing, and local governments should not encourage the public to purchase N95 or surgical masks.
"In addition to shelter-in-place and social distancing requirements, wearing a mask in public is an important tool to stop the community spread of this disease," San Mateo County Health Officer Dr. Scott Morrow said in a statement issued Thursday. "People with no or mild symptoms may have coronavirus and not know it. Wearing face coverings helps protect others from exposure."
The county Health Department also stressed against purchasing N95 and surgical masks. Instead, officials suggest different cloth materials, factory-made or hand-sewn, such as bandanas, T-shirts, scarves, sweatshirts or towels. As of Wednesday, the county had 453 confirmed cases of the coronavirus.
Shortly after the San Mateo County Health Department made its announcement, the Santa Clara County Public Health Department also recommended "non-medical" masks after evaluating its own guidelines on Thursday evening, while strongly discouraging the use of N95 and surgical masks.
The recommendation was based on the Centers for Disease Control and Prevention's understanding that the virus can be transmitted by people even before they show symptoms of COVID-19, according to a press release.
The county reported 63 new cases of the coronavirus earlier in the day, bringing its total to 1,019.
"The reasons health officials are now recommending face coverings is to reduce the spread of droplets as you go about your (essential) activities," Evelyn Ho, a senior community health planner for Santa Clara County, said Friday at a county COVID-19 briefing. "It also signals that we are in this together and that we are here to protect one another."
Ho also said that, along with social distancing, homemade face masks, bandanas and scarves provide additional protection. For repeated use, Ho reminded that masks should be washed with hot water and on a hot, dry cycle.
Since the outset and up until now, Santa Clara County has maintained the CDC's initial stance on facial protection. County health officials had said the CDC's instruction "does not recommend that people who are well wear a facemask to protect themselves from respiratory diseases, including COVID-19" and that it should be used by people who are showing symptoms of the virus, according to a press release issued March 5, when there were 20 confirmed COVID-19 cases in the county.
Other counties across the state have also recently made sharp turns on their advice regarding face coverings.
In an FAQ webpage of the Los Angeles County Public Health Department, the guidance instructed that "there is no need to wear a mask if you do not have symptoms." The information was removed from the page on Thursday evening, a day after Los Angeles Mayor Eric Garcetti recommended at a press conference that residents wear "nonmedical grade masks or facial coverings."
On Tuesday, the Riverside County Public Health Department also instructed the public to cover their nose and face when leaving the home for essential travel with bandanas, fabric masks or neck gaiters.
"Up until now, local officials have not recommended the large-scale use of face coverings, but circumstances have changed," county officials said in a statement.
The CDC and other health agencies have largely avoided encouraging the public to use face masks, partly to relieve the shortage of essential protective equipment needed by health care providers.
But since the first confirmed COVID-19 case in California on Jan. 25, the number of confirmed cases in the state has climbed to 11,125 with 241 deaths as of Thursday evening.
And with the curve of COVID-19 cases continuing its upward trajectory across the nation, the White House and the CDC now appear to be debating new guidelines on face masks, according to a report published Thursday by The New York Times.
The Stanford University Institute for Economic Policy Research also published this month a study on the effectiveness of medical masks in light of continued recommendations from the World Health Organization and the CDC against using masks in the community.
"Empirical evidence from existing observational studies and randomized trials supports the effectiveness of medical masks in reducing transmission of respiratory infections in a variety of settings," the study states.
"While the quality of evidence supporting the effectiveness of masks in health care settings is certainly better, the firm recommendation against masks in community settings appears incompatible with the available evidence."
On Friday afternoon, the CDC began recommending the use of face cloths especially in areas where a 6-feet distance is hard to maintain, such as grocery stores or pharmacies, and in "areas of significant community-based transmission."
"It is critical to emphasize that maintaining 6-feet social distancing remains important to slowing the spread of the virus," CDC said in a statement. "Cloth face coverings fashioned from household items or made at home from common materials at low cost can be used as an additional, voluntary public health measure."
Find comprehensive coverage on the Midpeninsula's response to the new coronavirus by Palo Alto Online, the Mountain View Voice and the Almanac here.