People cross Flagstaff Hill as the snow starts to fall, in Schenley Park, on their way to the Carnegie Mellon University campus, Tuesday, March 20, 2018, in the Oakland section of Pittsburgh. Yet another powerful storm bore down on the Northeast on Tuesday, with wind-whipped snow falling in parts of Pennsylvania and New Jersey as people grumbled and complained about a first day of spring that looked an awful lot like the last weeks of winter. (Photo by Darrell Sapp/Pittsburgh Post-Gazette via AP Photo)

A man wearing a mask looks on as he sells matresses in Manila, Philippines, January 8, 2020. (Photo by Willy Kurniawan/Reuters)

A model (R) wearing a dress adorned with chocolate stands backstage prior to a fashion show during the annual “Salon du Chocolat” expo in Seoul, South Korea on January 10, 2020. (Photo by Ed Jones/AFP Photo)

A woman plays billiards during a local championship at a sports hall in Yemen's capital Sanaa on December 16, 2019. (Photo by Mohammed Huwais/AFP Photo)

A model presents a creation by Obectra during Berlin Fashion Week in Berlin, Germany, January 15, 2020. The Berlin Fashion Week runs from​ 13 to 17 January. (Photo by Annegret Hilse/Reuters)

A couple wears face masks as they share a moment during sunset on January 31, 2020 in Hong Kong, China. With over 9800 confirmed cases of Novel coronavirus (2019-nCoV) around the world, the virus has so far claimed over 200 lives. (Photo by Anthony Kwan/Getty Images)

Gazan artist wears a face mask to raise awareness to the novel coronavirus (Covid-19) spread in Gaza Strip on March 25, 2020. (Photo by Ali Jadallah/Anadolu Agency via Getty Images)

A woman takes a picture of a goat in Llandudno as the spread of the coronavirus disease (COVID-19) continues, Llandudno, Wales, Britain, March 31, 2020. Like other countries affected by the global coronavirus crisis, the United Kingdom has imposed strict social distancing measures including shop and school closures, and the authorities are asking everyone to stay at home except for essential travel. (Photo by Carl Recine/Reuters)