A man wearing a face mask looks at the US-Mexico border from a bridge in the district of San Ysidro in San Diego, California, on April 22. Rich countries can close their borders, but if the pandemic rages on in the poor, overpopulated countries, the virus will continue to circulate. Photo: EPA-EFE
A man wearing a face mask looks at the US-Mexico border from a bridge in the district of San Ysidro in San Diego, California, on April 22. Rich countries can close their borders, but if the pandemic rages on in the poor, overpopulated countries, the virus will continue to circulate. Photo: EPA-EFE