Artists perform for medical workers at Metaxa hospital in Athens, Greece, on May 12, 2020. International Nurses Day was celebrated on Tuesday in hospitals and medical centers in Greece with speeches and concerts. (Xinhua/Marios Lolos)

Artists perform for medical workers at Metaxa hospital in Athens, Greece, on May 12, 2020. International Nurses Day was celebrated on Tuesday in hospitals and medical centers in Greece with speeches and concerts. (Xinhua/Marios Lolos)

Artists perform for medical workers at Metaxa hospital in Athens, Greece, on May 12, 2020. International Nurses Day was celebrated on Tuesday in hospitals and medical centers in Greece with speeches and concerts. (Xinhua/Marios Lolos)

Medical workers watch a performance at Metaxa hospital in Athens, Greece, on May 12, 2020. International Nurses Day was celebrated on Tuesday in hospitals and medical centers in Greece with speeches and concerts. (Xinhua/Marios Lolos)