CNN

Dr. Maria Van Kerkhove, the technical lead for the World Health Organization's Covid-19 response, chimed in on the current debate about when to wear face masks and who should be wearing them.

"What we recommend is that people who are sick wear masks -- medical masks, not N95 masks with respirators. Those must be reserved for our frontline workers who are caring for patients," she said.

"We also need people who are caring for those who are sick to be wearing the masks," she said.

She said right now, it's crucial that personal protective equipment in short supply be reserved for medical workers.

"We have to prioritize the use of masks for frontline workers, if that is one thing I can stress. Medical masks, respirators, gloves, gowns, these are people who are putting their lives on the line to help us, to care for other people and they must be protected," she said.

The WHO has been one of the strongest holdouts when it comes to recommending the widespread use of masks. US health officials recommended the same, but may be shifting course.

On Monday, the director of the US Centers for Disease Control and Prevention (CDC), Robert Redfield, told NPR that his organization was reviewing its guidelines and may recommend general mask use to guard against community infection. Trump said the US plans to release new recommendations on face masks in the coming days.

When asked about President Trump's suggestion that people use facial coverings like scarves, Van Kerkhove said the WHO is investigating.

"We are constantly looking at evidence, all the time, for the use of masks for anything that is related to this and related to health issues. We are talking with scientists around the world, including US CDC scientists," she said.

Read more about the global debate on face masks here:

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