1. From the Department of Medicine, Massachusetts General Hospital, and the Department of Medicine, Harvard Medical School — both in Boston (R.T.G., A.C.C.); and the Centre for Epidemic Response and Innovation, School for Data Science and Computational Thinking, Stellenbosch University, Stellenbosch (T.O.), and the KwaZulu-Natal Research Innovation and Sequencing Platform, School of Laboratory Medicine and Medical Sciences, University of KwaZulu-Natal, Durban (T.O., R.J.L.) — both in South Africa.