title: The emm-cluster typing system for Group A Streptococcus identifies epidemiologic similarities across the Pacific region.
abstract: BACKGROUND
  Group A Streptococcus (GAS)-related disease is responsible for high mortality and morbidity in the Pacific region. The high diversity of circulating strains in this region has hindered vaccine development due to apparently low vaccine coverage of type-specific vaccines.
  
  
  METHODS
  Prospective passive surveillance of all GAS isolates in New Caledonia was undertaken in 2012 using emm typing and emm-cluster typing. Molecular data were compared with the results from a prior study undertaken in the same country and with data from 2 other Pacific countries, Fiji and Australia.
  
  
  RESULTS
  A high incidence of invasive infection was demonstrated at 43 cases per 100 000 inhabitants (95% confidence interval, 35-52 cases per 100 000 inhabitants). Three hundred eighteen GAS isolates belonging to 47 different emm types were collected. In Noumea, only 30% of the isolates recovered in 2012 belonged to an emm type that was present in the same city in 2006, whereas 69% of the isolates collected in 2012 belonged to an emm cluster present in 2006. When comparing New Caledonian, Australian, and Fijian data, very few common emm types were found, but 79%-86% of the isolates from each country belonged to an emm cluster present in all 3 countries. A vaccine that could protect against the 10 most frequent emm clusters in the Pacific region would potentially provide coverage ranging from 83% to 92%.
  
  
  CONCLUSIONS
  This study confirms the high disease burden of GAS infection in New Caledonia and supports the added value of the emm-cluster typing system to analyze GAS epidemiology and to help inform global GAS vaccine formulation.
authors: Epidemiology of Infectious Diseases Research and Expertise Unit, Institut Pasteur de Nouvelle-Calédonie, Institut Pasteur International Network, Noumea, New Caledonia.
authors: Noémie
authors: N
authors: Baroux
authors: Epidemiology of Infectious Diseases Research and Expertise Unit, Institut Pasteur de Nouvelle-Calédonie, Institut Pasteur International Network, Noumea, New Caledonia.
authors: Eric
authors: E
authors: D'Ortenzio
authors: Epidemiology of Infectious Diseases Research and Expertise Unit, Institut Pasteur de Nouvelle-Calédonie, Institut Pasteur International Network, Noumea, New Caledonia.
authors: Nathalie
authors: N
authors: Amédéo
authors: Centre for International Child Health, University of Melbourne Group A Streptococcus Research Group, Murdoch Childrens Research Institute, Melbourne, Australia.
authors: Ciara
authors: C
authors: Baker
authors: Group A Streptococcus Research Group, Murdoch Childrens Research Institute, Melbourne, Australia.
authors: Barakat
authors: B
authors: Ali Alsuwayyid
authors: Dengue and Other Arboviruses Research and Expertise Unit, Institut Pasteur de Nouvelle-Calédonie, Institut Pasteur International Network, Noumea, New Caledonia.
authors: Myrielle
authors: M
authors: Dupont-Rouzeyrol
authors: Dengue and Other Arboviruses Research and Expertise Unit, Institut Pasteur de Nouvelle-Calédonie, Institut Pasteur International Network, Noumea, New Caledonia.
authors: Olivia
authors: O
authors: O'Connor
authors: Centre for International Child Health, University of Melbourne Group A Streptococcus Research Group, Murdoch Childrens Research Institute, Melbourne, Australia Department of General Medicine, Royal Children's Hospital Melbourne, Melbourne, Australia.
authors: Andrew
authors: A
authors: Steer
authors: Centre for International Child Health, University of Melbourne Group A Streptococcus Research Group, Murdoch Childrens Research Institute, Melbourne, Australia Laboratoire de Génétique et Physiologie Bactérienne, Institut de Biologie et de Médecine Moléculaires, Faculté des Sciences, Université Libre de Bruxelles, Gosselies, Belgium.
authors: Pierre R
authors: PR
authors: Smeesters
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000942:Antigens, Bacterial / Q000235:genetics*; D001425:Bacterial Outer Membrane Proteins / Q000235:genetics*; D002352:Carrier Proteins / Q000235:genetics*; D002648:Child; D002675:Child, Preschool; D016000:Cluster Analysis; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D008875:Middle Aged; D017720:Molecular Epidemiology; D058889:Molecular Typing; D009510:New Caledonia / Q000453:epidemiology; D011446:Prospective Studies; D013290:Streptococcal Infections / Q000453:epidemiology* / Q000382:microbiology*; D013297:Streptococcus pyogenes / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification; D055815:Young Adult
chemical_list: D000942:Antigens, Bacterial; D001425:Bacterial Outer Membrane Proteins; D002352:Carrier Proteins; C014689:streptococcal M protein
keywords: Streptococcus pyogenes; emm cluster; invasive diseases; typing; vaccine