Hospitals around the United States are preparing to treat an influx of patients with the highly infectious new coronavirus — and many health care providers are already beginning to run short on crucial respirator masks, The New York Times reported yesterday (March 9).

Several hospitals the Times spoke to said they have little more than a month's supply of respirator masks left, and that restocking the crucial masks has proven difficult as global cases of the new coronavirus, also called SARS-CoV-2, continue to climb daily.

"We can’t get any. Everything’s back ordered," Dr. Marc Habert, a pediatrician in Fishkill, N.Y., whose group works from eight offices in three counties, told the Times. "I was on a phone call earlier with the local department of health and they basically said the state has supplies, but we need to show we tried to order from three separate places first."

The masks, known as N95 respirator masks, are thicker and tighter fitting than normal surgical masks, blocking 95% of small airborne particles, according to the U.S. Food and Drug Administration (FDA). The masks are a crucial piece of personal protective equipment for health care workers tasked with treating large numbers of potential patients with COVID-19, the disease caused by the new coronavirus.

Related: Can wearing a facemask protect you from the new coronavirus?

The FDA and the Centers for Disease Control and Prevention (CDC) recommend that N95 masks should be used by medical professionals only, not by the general public. Global supplies of respirator masks are already dwindling after the prolonged coronavirus outbreak in China, the Times reported, and the widespread hoarding of masks by nervous citizens is exacerbating the problem.

According to the U.S. Department of Health and Human Services (HHS), health care facilities facing a shortage of supplies should first petition their local or state public health departments, many of which carry their own emergency supplies. If the state does not have enough, state officials may ask the HHS for assistance.

The federal government's Strategic National Stockpile — the nation's largest supply of emergency medical supplies, managed by the HHS — includes 12 million N95 masks and 30 million surgical masks. According to HHS estimates, that's only about 1% of the 3.5 billion masks that would be required in the U.S. in the first year if the outbreak escalates to pandemic levels. (To be considered a pandemic, the virus must be spreading uncontained across the world and result in severe cases of disease and death).

The department announced last week that 500 million more N95 masks will arrive in the next 18 months. To meet the projected demand for personal protective equipment across the globe, however, manufacturers must increase mask production by 40%, Tedros Adhanom Ghebreyesus, the World Health Organization’s director general, said in a statement on March 3.

In the meantime, individual countries have begun stockpiling their own supplies. Germany and South Korea have banned the export of medical masks, Bloomberg.com reported, and the United States government may be considering imposing similar restrictions.

If shortages worsen, health care workers may be asked to reuse masks for encounters with multiple patients, the CDC said. Providers who have already had the disease, called COVID-19, may have some protective immunity and should be the first to treat new patients if no masks are available.

Originally published on Live Science.