Genome of typhoid strain to be tackled
A project to sequencing the genome of the bacterium which causes typhoid fever (Salmonella typhi) is now underway. In collaboration with Professor Gordon Dougan from Imperial College of Science, Technology and Medicine, London, the Wellcome Trust funded Sanger Centre – the UK’s leading genome research institute – is to sequence the genome of S. typhi CT18, a strain of S. typhi which is highly infectious and multi-drug resistant. Over 870,000 pounds has been awarded to the project through the Wellcome Trust’s Beowulf initiative.
Typhoid fever is a continuing problem in the developing world, causing an estimated 600,000 deaths each year. Reports of specific strains of the disease becoming increasingly drug resistant have been made in South East Asia and new ways of treating this life threatening condition need to be developed. Sequencing S. typhi CT15 will provide scientists with an invaluable blueprint of the organism which could lead the way to new treatments.
Typhoid fever is an exclusively human disease, characterised by fever, headache and a variety of abdominal symptoms. The majority of cases are caused by the faecal contamination of food or water. The S. typhi CT15 strain was recently isolated in Vietnam by the Wellcome Trust Research Unit in collaboration with researchers at the Cho Quan Hospital, Ho Chi Minh City. This strain has been recognised as causing significant numbers of a highly virulent form of typhoid fever which is representative of the new multi-drug resistant strains in South East Asia.
“The cases identified by my colleagues in Vietnam are not isolated incidents. Typhoid fever is a continuing threat to the developing world and is rapidly becoming clinically untreatable, as current vaccines are either ineffective or expensive. With multi-drug resistant strains emerging, it is vital that we sequence the genome of S. typhi CT15 so that we are equipped with a detailed knowledge of the structure of this pathogen and understand how it works. It is only when we have this information that scientists world-wide will be able to make progress which will ultimately lead to the development of new treatments.”
Professor Gordon Dougan Imperial College of Science, Technology and Medicine, London
The sequencing of S. typhi CT15 will begin immediately and it is estimated that the project will take about 18 months. The Sanger Centre will release sequencing data onto the internet as soon as it is available (www.sanger.ac.uk).
