Julie Bennett1, Nicole J Moreland2, Deborah A Williamson3, Jonathan Carapetis4, Julian Crane5, Alana L Whitcombe2, Susan Jack6, Matire Harwood7, Michael G Baker8. 1. Department of Public Health, University of Otago, 23A Mein Street, Newtown, Wellington 6021, New Zealand. Electronic address: julie.bennett@otago.ac.nz. 2. Faculty of Medical and Health Sciences, The University of Auckland, Auckland, New Zealand; Maurice Wilkins Centre, The University of Auckland, Auckland, New Zealand. 3. Peter Doherty Institute for Infection and Immunity, University of Melbourne, Victoria, Australia. 4. Telethon Kids Institute and Perth Children's Hospital, University of Western Australia, Perth 6009, Australia. 5. Department of Medicine, University of Otago, Wellington, New Zealand. 6. Public Health South, Southern District Health Board, Dunedin, New Zealand. 7. Faculty of Medical and Health Sciences, The University of Auckland, Auckland, New Zealand. 8. Department of Public Health, University of Otago, 23A Mein Street, Newtown, Wellington 6021, New Zealand; Maurice Wilkins Centre, The University of Auckland, Auckland, New Zealand.
Abstract
OBJECTIVES: Rates of acute rheumatic fever, a sequelae of group A Streptococcal (GAS) infection, remain unacceptably high in Indigenous Māori and Pacific children in New Zealand. This prospective study aimed to describe GAS antibody titres in healthy children (5-14 years) by ethnicity, and to determine how paired titres vary with GAS culture positive and negative pharyngitis, and GAS skin infections. METHODS: Analysis included 887 children (32% Māori, 36% Pacific, 33% European/Other) from Auckland, New Zealand. Cases comprise 772 children who had a sore throat or skin infection, which resulted in a swab taken for culture. Healthy controls were asymptomatic (N = 154) and matched by age, ethnicity and region. All participants had a serum sample, with a second sample collected from cases only. Sera were analysed for anti-streptolysin O (ASO) and anti-DNase-B (ADB) antibodies. RESULTS: Healthy Māori and Pacific children had higher GAS antibody titres than healthy European/Other children. Children with GAS-positive sore throat had the highest mean ASO titres and children with GAS-positive skin infection had the highest mean ADB titres. When a two-fold increase or an upper limit of normal cut-off (ASO 450 IU/ml, ADB 400 U/ml) was applied to titres from children with GAS-positive sore throat, 62.1% were classified as having serologically confirmed GAS pharyngitis and 37.9% had GAS detected without serological response. CONCLUSIONS: Elevated ASO titres were associated with GAS pharyngitis and elevated ADB titres were associated with GAS skin infections in New Zealand children. Higher ASO/ADB titres in healthy Māori and Pacific children could indicate a greater prior exposure to GAS infections.
OBJECTIVES: Rates of acute rheumatic fever, a sequelae of group A Streptococcal (GAS) infection, remain unacceptably high in Indigenous Māori and Pacific children in New Zealand. This prospective study aimed to describe GAS antibody titres in healthy children (5-14 years) by ethnicity, and to determine how paired titres vary with GAS culture positive and negative pharyngitis, and GAS skin infections. METHODS: Analysis included 887 children (32% Māori, 36% Pacific, 33% European/Other) from Auckland, New Zealand. Cases comprise 772 children who had a sore throat or skin infection, which resulted in a swab taken for culture. Healthy controls were asymptomatic (N = 154) and matched by age, ethnicity and region. All participants had a serum sample, with a second sample collected from cases only. Sera were analysed for anti-streptolysin O (ASO) and anti-DNase-B (ADB) antibodies. RESULTS: Healthy Māori and Pacific children had higher GAS antibody titres than healthy European/Other children. Children with GAS-positive sore throat had the highest mean ASO titres and children with GAS-positive skin infection had the highest mean ADB titres. When a two-fold increase or an upper limit of normal cut-off (ASO 450 IU/ml, ADB 400 U/ml) was applied to titres from children with GAS-positive sore throat, 62.1% were classified as having serologically confirmed GAS pharyngitis and 37.9% had GAS detected without serological response. CONCLUSIONS: Elevated ASO titres were associated with GAS pharyngitis and elevated ADB titres were associated with GAS skin infections in New Zealand children. Higher ASO/ADB titres in healthy Māori and Pacific children could indicate a greater prior exposure to GAS infections.
Authors: Julie Bennett; Nicole J Moreland; Jane Zhang; Julian Crane; Dianne Sika-Paotonu; Jonathan Carapetis; Deborah A Williamson; Michael G Baker Journal: Lancet Reg Health West Pac Date: 2022-06-24
Authors: Santosh Kumar Saha; Kamrun Nahar Choudhury; Salma Zareen; Sabrina Mousum; Mohammad Abdullah Al Mamun; M Atiqul Haque Journal: SAGE Open Med Date: 2022-06-28
Authors: Alana L Whitcombe; Reuben McGregor; Julie Bennett; Jason K Gurney; Deborah A Williamson; Michael G Baker; Nicole J Moreland Journal: J Infect Dis Date: 2022-08-12 Impact factor: 7.759