As healthcare workers and hospitals face shortages across the United States amid the coronavirus pandemic, the Centres for Disease Control and Prevention has released new guidelines for using face masks.

Shortages in surgical and respirator masks started after citizens panic bought boxes in stores and online so they could wear when out. But this decision has since left hospitals short of the necessary facial guard.

Now the CDC is advising using homemade masks, such as a bandana or scarf, as a “last resort” to treat patients with Covid-19. This guideline is recommended only if no other face masks are available to the healthcare worker.

Although these guidelines were updated to allow this practice, the CDC still acknowledged that a bandana or scarf tied around the face was not considered personal protection equipment.

“Their capability to protect HCP (healthcare professionals) is unknown,” the CDC wrote. “Caution should be exercised when considering this option.”

In a statement released on Wednesday, the American Association of Nurse Practitioners strongly urged the Trump administration to prioritise healthcare professionals having access to personal protection equipment.

“NPs and all health care providers urgently need personal protection equipment, such as masks and gowns, to ensure their safety and that of all health care providers treating patients with Covid-19,” the organisation said. “Supplies are also necessary to implement testing as well as respirators for treating patients. We asked the Administration to support this priority to the fullest extent of its authority.”

National Nurses United (NNU) also pushed back on “weakening” standards and protections during the pandemic.

“If nurses and healthcare workers aren’t protected, that means patients and the public are not protected,” NNU executive director Bonnie Castillo said in a press release. “This is a major public health crisis of unknown proportions. Now is not the time to be weakening our standards and protections, or cutting corners. Now is the time we should be stepping up our efforts.”

The CDC has also recommended health professionals to reuse masks, use expired masks, or prioritising use of masks during crisis situations.

Cases in the US have doubled in the last two days with testing ramping up across the country. At least 11,274 people have tested positive for Covid-19 and 157 have died, according to Johns Hopkins.

During a press conference on Thursday, President Donald Trump was asked about the shortage of medical supplies, including masks, and what his administration was doing to address these concerns.

He pivoted the question to Vice President Mike Pence. “We have put priority on making sure people who are providing healthcare services have what they need,” the vice president said.