Turning the tide on Tuberculosis with surveillance and solutions

With cases of Tuberculosis (TB) increasing in Scotland, Hazel Henderson, Consultant in Public Health and Lead of the Respiratory Bacterial Pathogens team at Public Health Scotland (PHS), has written in our latest blog about the importance of surveillance in understanding and beating this persistent, curable and preventable disease.  

In 2024, 1.23 million people died from Tuberculosis (TB) globally, and 10.7 million were diagnosed with the bacterial infection. It is now, once again, the world’s deadliest disease. 

At Public Health Scotland (PHS), we’re responsible for the enhanced surveillance of TB cases across Scotland. We collect, analyse and interpret data to support the three main purposes of active TB surveillance - developing understanding, informing policy, and prompting action. Our work aims to protect individuals and communities, with the longer-term aim of achieving TB elimination in Scotland.  

It’s easy to think of TB as a thing of the past in Scotland – a disease linked to overcrowding and poor sanitation. TB is curable and has been since the mid-1950s, and so we’ve been accustomed to living in a world without TB as a common illness. Indeed, within Scotland we were on-track to achieve TB elimination. However, following the COVID-19 pandemic, progress towards TB control began to reverse globally. We’ve seen TB increase since 2022 in Scotland, with a 33% increase in cases between 2022 and 2024 - taking us back to levels last observed in 2018.  

To address this increase, and get us back on track, PHS is harnessing the powers of data, collaboration and innovation to fight this disease. 

Surveillance = Information for Action 

The World Health Organization (WHO) monitors the global TB disease burden and epidemiological trends – patterns or changes in how a disease like TB spreads and affects people over time  – with a strong emphasis on the importance of high-quality surveillance.  

PHS performs the same role in Scotland, where TB is a notifiable disease under the Public Health Scotland Act (2008) – this means it must be reported as soon as it Is suspected or diagnosed. We assess the disease burden and monitor unusual occurrences, such as outbreaks and clusters of TB, that require a response from health services. By identifying gaps in programmes and provisions, we can help to prioritise interventions and the allocation of resources.   

Information for understanding 

Scotland has rich data that can be used to identify groups of people who are at higher risk of contracting and becoming seriously ill from TB.  

We collect ‘enhanced surveillance’ data for each case, which enables us to monitor case numbers, geographical distribution, characteristics (including age, sex, socioeconomic status and risk factors), drug resistance patterns, treatment completion outcomes, and disease outcomes.  

These data and their analysis tell us that TB disproportionately affects Scotland’s most vulnerable people. In fact, being a refugee or asylum seeker is one of the most reported risk factors for TB. In Scotland, people born outside the UK are over 28 times more likely to be diagnosed with TB than those born within the UK. We have also observed a widening of inequalities associated with TB. Despite a reduction in the TB incidence between the most and least deprived groups in Scotland, this gap has begun to widen in recent years. 

Information to inform policy  

The increase in TB cases has prompted the Scottish Government to review TB services.  As part of the national TB Network, PHS has been working with clinicians, nurses, health protection professionals and the Scottish Government’s policy team to produce a report with findings to be implemented to help improve service provision. Its clear recommendations will outline TB services that are fit for purpose and equipped to cope with the dramatic increase in case numbers in Scotland. 

The data we collect helps us understand how TB passes from person to person and highlights which groups are most at risk, which helps direct interventions. One of the initiatives we’ve introduced is piloting a programme in two health boards to test and treat people with latent TB (who have the infection but aren’t sick yet). This targeted approach is both effective and affordable, helping prevent TB from developing further.  

The importance of collaboration 

At PHS we understand the power of collaboration, and our work with the Scottish Government, local health boards, and academic institutions is key to understanding and tackling the increase in TB cases in Scotland. 

Our team is proud to have recently joined the National TB Surveillance system (NTBS), a unique collaboration with the other UK nations and the first UK-wide infectious disease enhanced surveillance system. The NTBS enables the UK-wide electronic recording and reporting of TB cases and meets the WHO standards and benchmarks for surveillance.   

This real-time system includes data on drug sensitivity, species and genomic relatedness. It will help to improve Scotland’s response to TB infections, strengthen our understanding and help to inform policy. The NTBS also plugs us in to global reporting, meaning that Scotland is benefitting from and contributing to international expertise. 

Responding to a global challenge 

TB is not just an issue for Scotland; it’s a global challenge. Collaboration across the world, shared knowledge and expertise, coordinated prevention and response systems, and international commitment are our best weapons against this ancient and pervasive disease.  

We’re rising to this challenge, protecting the population, and contributing to the global fight by building a robust surveillance system, deploying innovative prevention initiatives, and nurturing strong partnerships at home and abroad. 

View the latest Tuberculosis Annual Report for Scotland (2024)

Read our recently published research article to find out more about the the latent TB pilot  

Read our Getting It Right First Time (GIRFT) Review of Tuberculosis (TB) in Scotland