South Africa, Colombia and other countries that lost out in the global race for coronavirus vaccines are taking a more combative approach towards drugmakers and pushing back on policies that deny cheap treatment to millions of people with tuberculosis and HIV. In the COVID-19 pandemic, rich countries bought most of the world’s vaccines early, leaving few shots for poor countries and creating a disparity the World Health Organization called “a catastrophic moral failure.” Now, poorer countries are trying to become more self-reliant “because they’ve realized after COVID they can’t count on anyone else,” said Brook Baker, who studies treatment-access issues at Northeastern University.