All adult patients admitted to the hospitals (3 in South Africa [Tygerberg Academic Hospital, Cape Town; Grootte Schuur Academic Hospital, Cape Town; Chris Hani Baragwanath Hospital, Johannesburg]; 2 in Kenya [Aga Khan University Hospital, Nairobi; Mbagathi district hospital, Nairobi] and 1 in Ghana [Korle Bu Teaching Hospital, Accra]) during the defined study periods will be eligible for inclusion in the study.