Explainer: why is getting medical oxygen for Covid patients in some countries so difficult?

As India's hospitals struggle to keep pace with demand, the pandemic has exposed global market failures, lack of knowledge and anticipation

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New waves of the Covid-19 pandemic in countries, such as India and Kenya have exposed the poor management of oxygen supplies. Prof Trevor Duke, editor of the World Health Organization (WHO) guidelines on oxygen therapy for children, answered questions on what countries with limited resources can do to secure better supplies.