TULSA, Okla. (AP) — A top White House coronavirus adviser continued to press Sunday for people to cover their faces and to social distance to fight the global pandemic during a stop in Oklahoma, where Republican Gov. Kevin Stitt has resisted imposing a statewide mask order.

Dr. Deborah Birx led the roundtable discussion at the Oklahoma State University Center for Health Sciences in Tulsa. The meeting was closed to journalists, but state and local officials who attended told the Tulsa World that Birx was unwavering on the necessity for masks and distancing in public.

"She said she came to Oklahoma, as she is other states, asking people to change their behavior to protect others," said Joy Hofmeister, state superintendent of public schools.

A statement from Stitt's office said Birx complimented Oklahoma's push to use saliva testing for COVID-19, the disease caused by the coronavirus.

"There are a lot of levers we can pull, but at this point we are in really good shape," Stitt said in the statement. "We have to be very cautious as kids are going back to school."

The state Department of Emergency Management has begun sending personal protective equipment for schools statewide as classes begin, some in-person and some by distance learning.

Items including masks, gloves, gowns and face shields were sent to distribution sites in Oklahoma and Tulsa counties Friday for schools in those regions, the department said, and deliveries to other regional sites will begin Monday.

Tulsa Mayor G.T. Bynum put a local mask order in place but has been vocal about his frustration with nearby suburbs that haven't.

"(Birx) said they have not seen a state or city put in a mask mandate and it not make an impact," Bynum told the World. "The patients in Tulsa's hospitals are not all from Tulsa."

Birx declined to speak to the media before leaving Tulsa, citing a tight travel schedule. She is on a Midwestern tour that has included stops in Nebraska and Kansas. She is scheduled to be in Arkansas on Monday.

The Muscogee (Creek) Nation said Birx also met with tribal health officials.

The reported number of coronavirus cases in Oklahoma increased by 544 on Sunday with four more deaths due to COVID-19, the disease caused by the virus, according to the Oklahoma State Department of Health.

There are 48,342 total confirmed cases since the pandemic began and 661 deaths, up from 47,798 cases and 657 deaths Saturday, the department said. The true number of cases in Oklahoma is likely higher because many people have not been tested, and studies suggest people can be infected and not feel sick.

The department reported 7,457 active cases, and that 40,224 people have recovered.

For most people, the new coronavirus causes mild or moderate symptoms, such as fever and cough that clear up in two to three weeks. For some, especially older adults and people with existing health problems, it can cause more severe illness, including pneumonia, and death. The vast majority of people recover.