Global Strep A vaccine one step closer
Streptococcus genomes reveal potential vaccine targets present in over 20 countries worldwide
The search for a global Strep A vaccine has narrowed after researchers sequenced the DNA of more than 2,000 Group A Streptococcus samples from around the world. Researchers from the Wellcome Sanger Institute, the University of Cambridge, the Peter Doherty Institute for Infection and Immunity (Doherty Institute) in Australia, and the University of Queensland, Australia, revealed the differences between strains from more than 20 countries, and identified potential vaccine targets present across most strains.
Published today (27 May) in Nature Genetics, the 10-year project found there were some molecular targets present in bacterial strains from all 20 countries, including the UK, Australia and India, which point to the possibility of developing an effective global vaccine against Strep A.
Group A Streptococcus bacteria, commonly known as Strep A, is one of the top 10 causes of death from infectious diseases worldwide. It is estimated to cause more than half a million deaths per year*, mainly in low-income regions of the world. It can cause many different infections, ranging from Strep throat, which is widely seen in the developed world, to scarlet fever and rheumatic heart disease, which are constantly present and considered endemic in lower-income areas of the globe.
There is no effective vaccine yet for Strep A, and the search for a vaccine is hampered by the variety of Strep A strains. Until now, most of the information has come from high-income areas such as the UK and US, however, very little is known about Strep A in the low-income areas of the world where it causes the most problems. This means that current vaccine candidates may not be effective in all areas.
To remedy this, the researchers collected more than 2,000 samples of Strep A from 22 countries around the world, including countries in Africa and the Pacific, New Zealand and Australian Aboriginal communities. By sequencing and analysing the DNA of each sample, they were able to determine the genes present in each strain, and see the variety in strains across the world.
The project found that current leading Strep A vaccine candidates would have limited coverage in the low-income areas where Strep A is endemic and the vaccine is most needed.
“Using large-scale genomic sequencing, we identified the existence of more than 290 genetically different lineages of clinically important Strep A, highlighting the challenges of designing an effective global vaccine. However, using all the data we collected, we narrowed down common genes in almost all strains of Strep A globally. This is a tremendous step forward in identifying what may work as a global vaccine candidate.”
Dr Mark Davies Lead author from the Wellcome Sanger Institute and University of Melbourne’s Doherty Institute
“Millions of people around the world are affected by Strep A. It can cause a range of conditions, from sore throats and outbreaks of scarlet fever in the UK, to infections leading to rheumatic heart disease in populations such as the Australian Aboriginal population. In addition to aiding research into a vaccine, genomic data from our study will help researchers understand how Strep A causes disease and why it is different in high-income areas to endemic regions.”
Prof Gordon Dougan An author from the Wellcome Sanger Institute and University of Cambridge
“This research has the potential to fast track a much-needed Strep A vaccine as developers and the wider scientific community can now use our database to identify the most common genes as vaccine targets. I believe a global vaccine is possible and these research findings, in addition to increased funding commitments, will renew the momentum towards the search for a global vaccine.”
Professor Mark Walker A senior author on the paper and Director of Australian Infectious Diseases Research Centre, from the University of Queensland
Mark R Davies et al. (2019) Atlas of group A streptococcal vaccine candidates compiled using large scale comparative genomics. Nature Genetics. DOI: 10.1038/s41588-019-0417-8
*Statistics on the burden of group A streptococcal diseases from: Carapetis JR, Steer AC, Mulholland EK, Weber M. The global burden of group A streptococcal diseases. Lancet Infect Dis 2005; 5(11): 685–94.
This work was supported by Wellcome, the National Health and Medical Research Council (NHMRC),
the Coalition to Accelerate New Vaccines Against Streptococcus (CANVAS), and European Union’s Seventh Framework Programme.
Finding solutions to prevent, treat and cure infectious diseases and understanding the complexities of the immune system requires innovative approaches and concentrated effort. This is why The University of Melbourne – a world leader in education, teaching and research excellence – and The Royal Melbourne Hospital – an internationally renowned institution providing outstanding care, treatment and medical research – have partnered to create the Peter Doherty Institute for Infection and Immunity (Doherty Institute); a centre of excellence where leading scientists and clinicians collaborate to improve human health globally. Website: doherty.edu.au Facebook: /DohertyInstitute Twitter: @TheDohertyInst Instagram: #DohertyInstitute
The Sanger is one of the world’s leading genome and biodata institutes. Through its ability to conduct research at scale, it is able to engage in bold and long-term exploratory projects that are designed to influence and empower science globally. Institute research findings, generated through its own research programmes and through its leading role in international consortia, are being used to develop new diagnostics and treatments for human disease and to understand life on Earth. Find out more at www.sanger.ac.uk or follow @sangerinstitute on Twitter, Facebook, LinkedIn and on our Blog
Wellcome exists to improve health by helping great ideas to thrive. We support researchers, we take on big health challenges, we campaign for better science, and we help everyone get involved with science and health research. We are a politically and financially independent foundation. https://wellcome.org/
Related blog posts
13 Apr 2015
Being part of the herd saves lives
13.04.15 Stopping the leading cause of child death starts with you. Rebecca Gladstone explains how widespread vaccination protects the ...
17 Jun 2021
Study identifies trigger for ‘head-to-tail’ axis development in human embryo
Researchers have mapped, in new detail, the genetic changes that a human embryo goes through as it develops.
14 Jun 2021
Computer method to help predict outcomes and tailor treatments for patients with inherited heart diseases
Clinicians and scientists analysed how individual genetic changes affect the heart muscle and created a new computer tool to integrate genomic ...