Members of the Chinese anti-epidemic medical expert team prepare to board a helicopter in Vientiane, Laos, April 7, 2020. The Chinese anti-epidemic medical expert team, divided into two groups, have gone to northern and southern Lao provinces of Luang Prabang and Champassak, to join the local governments and medical workers to prevent and control the COVID-19 outbreak. (Chinese anti-epidemic medical expert team/Handout via Xinhua)

A member of the Chinese anti-epidemic medical expert team (1st R) looks into a local hospital's situation on COVID-19 diagnosis and treatment in northern Lao's Luang Prabang, April 7, 2020. The Chinese anti-epidemic medical expert team, divided into two groups, have gone to northern and southern Lao provinces of Luang Prabang and Champassak, to join the local governments and medical workers to prevent and control the COVID-19 outbreak. (Chinese anti-epidemic medical expert team/Handout via Xinhua)

Members of the Chinese anti-epidemic medical expert team look into a local hospital's situation on COVID-19 diagnosis and treatment in southern Lao's Champassak province, April 7, 2020. The Chinese anti-epidemic medical expert team, divided into two groups, have gone to northern and southern Lao provinces of Luang Prabang and Champassak, to join the local governments and medical workers to prevent and control the COVID-19 outbreak. (Chinese anti-epidemic medical expert team/Handout via Xinhua)

A member of the Chinese anti-epidemic medical expert team (1st R) looks into a local hospital's situation on COVID-19 diagnosis and treatment in southern Lao's Champassak province, April 7, 2020. The Chinese anti-epidemic medical expert team, divided into two groups, have gone to northern and southern Lao provinces of Luang Prabang and Champassak, to join the local governments and medical workers to prevent and control the COVID-19 outbreak. (Chinese anti-epidemic medical expert team/Handout via Xinhua)

A member (C) of the Chinese anti-epidemic medical expert team looks into a local hospital's situation on COVID-19 diagnosis and treatment in northern Lao's Luang Prabang, April 7, 2020. The Chinese anti-epidemic medical expert team, divided into two groups, have gone to northern and southern Lao provinces of Luang Prabang and Champassak, to join the local governments and medical workers to prevent and control the COVID-19 outbreak. (Chinese anti-epidemic medical expert team/Handout via Xinhua)