aDivision of Medical Virology, Institute of Infectious Disease and Molecular Medicine, Department of Pathology, Faculty of Health Sciences, University of Cape Town and National Health Laboratory Service, Cape Town

bCentre for the AIDS Programme of Research in South Africa, Durban, South Africa

cDepartment of Microbiology, Immunology & Tropical Medicine, School of Medicine and Health Sciences, George Washington University, Washington, DC, USA

dSA MRC Antibody Immunity Research Unit, School of Pathology, University of the Witwatersrand

eNational Institute for Communicable Diseases of the National Health Laboratory Services, Johannesburg, South Africa

Correspondence to Penny L. Moore, SA MRC Antibody Immunity Research Unit, School of Pathology, University of the Witwatersrand, Johannesburg, South Africa. E-mail: [email protected]