National Health Laboratory Services (NHLS) - National Institute for Communicable Diseases, University of KwaZulu-Natal - Centre for the AIDS Programme of Research in South Africa (CAPRISA), National Health Laboratory Services (NHLS) - National Institute for Communicable Diseases, National Health Laboratory Services (NHLS) - National Institute for Communicable Diseases, National Health Laboratory Services (NHLS) - National Institute for Communicable Diseases, National Health Laboratory Services (NHLS) - National Institute for Communicable Diseases, National Health Laboratory Services (NHLS) - National Institute for Communicable Diseases, National Health Laboratory Services (NHLS) - Centre for Respiratory Diseases and Meningitis, National Health Laboratory Services (NHLS) - Centre for Respiratory Diseases and Meningitis, affiliation not provided to SSRN, National Health Laboratory Services (NHLS) - National Institute for Communicable Diseases and National Health Laboratory Services (NHLS) - Centre for Respiratory Diseases and Meningitis

National Health Laboratory Services (NHLS) - Centre for Respiratory Diseases and Meningitis, Government of the United States of America - Division of Influenza, National Health Laboratory Services (NHLS) - National Institute for Communicable Diseases, National Health Laboratory Services (NHLS) - National Institute for Communicable Diseases, National Health Laboratory Services (NHLS) - National Institute for Communicable Diseases, National Health Laboratory Services (NHLS) - Centre for Respiratory Diseases and Meningitis, National Health Laboratory Services (NHLS) - Centre for Respiratory Diseases and Meningitis, National Health Laboratory Services (NHLS) - National Institute for Communicable Diseases, Centers for Disease Control and Prevention (CDC) - Influenza Division, Genesis Analytics, Genesis Analytics, Genesis Analytics, Genesis Analytics, Genesis Analytics, University of the Witwatersrand, Epicentre Health Research, University of the Witwatersrand - Perinatal HIV Research Unit, University of the Witwatersrand - Perinatal HIV Research Unit, National Health Laboratory Services (NHLS) - National Institute for Communicable Diseases, Ampath Pathology and National Health Laboratory Services (NHLS) - Centre for Respiratory Diseases and Meningitis

National Health Laboratory Services (NHLS) - National Institute for Communicable Diseases, National Health Laboratory Services (NHLS) - National Institute for Communicable Diseases, National Health Laboratory Services (NHLS) - National Institute for Communicable Diseases, National Health Laboratory Services (NHLS) - National Institute for Communicable Diseases, National Health Laboratory Services (NHLS) - National Institute for Communicable Diseases, National Health Laboratory Services (NHLS) - Centre for Respiratory Diseases and Meningitis, National Health Laboratory Services (NHLS) - National Institute for Communicable Diseases, University of Cape Town (UCT) - Department of Pediatrics and Child Health, affiliation not provided to SSRN, Government of the United States of America - Division of Influenza, National Health Laboratory Services (NHLS) - National Institute for Communicable Diseases, National Institute For Communicable Diseases Of South Africa - Division of Public Health Surveillance and Response, Division of Public Health Surveillance and Response, National Health Laboratory Services (NHLS), National Institute For Communicable Diseases Of South Africa - Division of Public Health Surveillance and Response, National Health Laboratory Services (NHLS) - National Institute for Communicable Diseases and National Health Laboratory Services (NHLS) - Centre for Respiratory Diseases and Meningitis

National Health Laboratory Services (NHLS) - Centre for Respiratory Diseases and Meningitis, National Health Laboratory Services (NHLS) - Centre for Respiratory Diseases and Meningitis, National Health Laboratory Services (NHLS) - Centre for Respiratory Diseases and Meningitis, Centers for Disease Control and Prevention (CDC) - Influenza Division, National Health Laboratory Services (NHLS) - Centre for Respiratory Diseases and Meningitis, National Health Laboratory Services (NHLS) - Centre for Respiratory Diseases and Meningitis, National Health Laboratory Services (NHLS) - Centre for Respiratory Diseases and Meningitis, University of the Witwatersrand - Perinatal HIV Research Unit, University of the Witwatersrand - MRC/Wits Rural Public Health and Health Transitions Research Unit, University of the Witwatersrand - Perinatal HIV Research Unit, Chris Hani Baragwanath Academic Hospital - Perinatal HIV Research Unit, University of the Witwatersrand - MRC/Wits Rural Public Health and Health Transitions Research Unit, University of the Witwatersrand - MRC/Wits Rural Public Health and Health Transitions Research Unit, National Health Laboratory Services (NHLS) - Centre for Respiratory Diseases and Meningitis, National Health Laboratory Services (NHLS) - Centre for Respiratory Diseases and Meningitis, National Health Laboratory Services (NHLS) - Centre for Respiratory Diseases and Meningitis, South African Medical Research Council - Health Systems Research Unit, North-West University - Unit for Environmental Sciences and Management, North-West University - Unit for Environmental Sciences and Management, National Health Laboratory Services (NHLS) - Centre for Respiratory Diseases and Meningitis, Government of the United States of America - Division of Influenza and Independent