In a world-first, Public Health England (PHE) in the West Midlands is using Whole Genome Sequencing (WGS) to identify different strains of tuberculosis.
This is the first time that WGS has been used as a diagnostic solution for managing a disease on this scale anywhere in the world. This builds on WGS based services for public health investigation of infectious diseases, which offer the opportunities for faster, cheaper and more accurate diagnostics than other testing methods.
The technique, developed in conjunction with the University of Oxford and carried out at PHE’s laboratory in Birmingham, allows faster and more accurate diagnoses, meaning patients can be treated with precisely the right medication more quickly. Where previously it could take up to a month to confirm a diagnosis of TB, confirm the treatment choices and to detect spread between cases; this can now be done in just over a week by at the Birmingham lab. This slows the spread of the disease and boosts the fight against anti-microbial resistance (AMR).
Some strains of TB are called ‘drug resistant’ which means they need treating differently to conventional types. With WGS diagnosis, patients who have a strain of TB which is resistant to specific drugs will receive the right medication from the start of their treatment. This will shorten the time that patients are infectious and so stop the spread and reduce the prevalence of drug-resistant TB and costs to NHS in hospital care.
Dr Grace Smith, PHE Interim Director National Mycobacterial Reference Service, National Infection Service (based at the Birmingham laboratory), said: “The use of whole genome sequencing to diagnose, detect drug resistance and very accurately type TB is a world first for any disease on this scale. By working closely with our partners, we are now able to use cutting edge science to effectively treat these patients with the right medicines quickly. We are immensely proud of the contribution this makes to the prospects of better treatment of TB globally. This approach will also increasingly be used for many other infectious diseases. Our ambition is to achieve this as quickly as possible so many infections can be better diagnosed and treated.”
Dr Martin Dedicoat, TB clinical lead for Birmingham and Solihull (Heart of England Foundation Trust), said: “Whole genome sequencing for TB means quicker more accurate diagnosis for patients. It has helped patients start appropriate treatment within days as opposed to weeks. Also timely identification of TB transmission is helping safe guard the public.”
Dr Nic Coetzee, TB lead Consultant in Communicable Disease Control for PHE West Midlands, said: “The number of cases of TB in England has declined by 30% over the last four years; with 5,758 confirmed cases in 2015 compared to 8,280 in 2011 nationally, while the West Midlands saw 708 cases in 2015 compared to 1,004 in 2011. Despite this downward trend, England still has one of the highest rates of TB in Western Europe, and the West Midlands region has the second highest rate of TB in the country at 12.3 cases per 100,000 head of population – with London being highest at a rate of 26.2 cases per 100,000.
“PHE and NHS England are working with local and national partners to continue this decrease by actively implementing the Collaborative TB Strategy for England. This will contribute to the World Health Organization’s goal of eliminating TB as a public health problem by 2035. There is significant variation in rates of TB in England, depending on population characteristics, socioeconomic factors and level of local risk. Certain groups are disproportionately affected including some migrant groups, people who misuse alcohol or drugs, people who are homeless and those with prison histories. In the West Midlands we have been working with local prisons and homeless charities to help earlier diagnosis and treatment of people at greater risk.”
PHE is already pioneering the development and early use of WGS to enable the investigation and control of multiple infectious diseases. In future, the application of WGS in other conditions will allow us to test and treat patients at the bed side, rather than needing to wait days and sometimes weeks for results. The implementation of this technology will contribute to achieving the Government’s ambition of sequencing 100,000 genomes, a project which will ultimately allow us to better understand major diseases and how to treat them.