THE exchange began with the kind of language rarely directed at a member state by a United Nations agency head - raw, personal, and historically charged. Dr Tedros Adhanom Ghebreyesus, Director-General of the World Health Organisation, broke from the measured diplomatic register of multilateral institutions to deliver a searing public indictment of South Africa on his official social media platform, as anti-immigration protests convulsed the country and hundreds marched on Parliament. "It is profoundly heartbreaking to witness another surge of xenophobic violence in South Africa this week," Tedros wrote. "Hundreds have marched on Parliament, thousands of families have been displaced,…