Ancient infections still shape modern health, despite being hidden from the headlines
Many people in the UK assume ancient diseases like tuberculosis (TB) are a thing of the past, but outbreaks continue to pose serious threats worldwide. In this Q&A, Associate Professor Conor Meehan, Lecturer in Epidemiology at NTU, explores how pathogens spread, why some remain major causes of illness and death, and how genomic research can help track outbreaks and detect drug resistance.
Published on 12 June 2026
Categories: Press office; Research; School of Science and Technology;
Why do many people think diseases like tuberculosis (TB) are a thing of the past, when they’re still a major global public health threat?
Diseases like TB, malaria and leprosy have been around for thousands of years and still infect millions worldwide.
However, each is a slow disease and so usually won’t make headlines about outbreaks and rapid responses. For example, it can be years between someone being infected with Mycobacterium tuberculosis – the bacteria which causes TB – and when they start to show symptoms.
These diseases are also endemic in many parts of the world, meaning they are constantly present in the population and difficult to eradicate, so it’s an ongoing battle more so than a new threat. Although TB is present in the UK, at around 6000 cases a year and rising, it is not a top concern for many people outside of the geographical pockets where most cases occur, such as in high deprivation areas.
What can studying the DNA of pathogens tell us about how disease spreads and evolves?
The ability to sequence the genome of pathogens has become a core tool in biological research, including the work we are doing in NTU’s Antimicrobial Resistance, Omics and Microbiota research group, as well as clinical diagnostics within the NHS and public health surveillance, such as with the UK Health Security Agency (UKHSA).
By comparing the genome sequences of pathogens infecting different people, we can see whether cases may be linked in an outbreak. It’s a bit like building a family tree of the pathogen and identifying which samples are most closely related.
We can also examine these genomes for signs of antimicrobial resistance or genetic changes linked to more severe disease. This technology is continuing to advance. For example, a project I’m working on with UKHSA, called mSCAPE, is examining whether metagenomics – sequencing all the DNA from microbes in a clinical sample – could replace conventional surveillance systems for quick detection of seasonal trends and novel pathogens.
Could where you live or your income really change your risk of catching certain infections?
It is more about where you sit on what is called the deprivation index. This scale shows how a given area fares in terms of the needs of its people, such as access to good medical care, overall healthy lifestyle (e.g. malnutrition status) and amenities; it often acts as a proxy poverty indicator. In general, the lower on this index the poorer the higher the deprivation and the worse the health of the general population in that area. Poorer health and overcrowding are two strong risk factors for increasing your chance of catching infections. This is especially true for respiratory diseases that require close contact and coughing to spread, like TB.
Why is it so important to get the right treatment for infections, and how does antimicrobial resistance make this more complicated?
Treating an infection not only stops your symptoms but also kills off the pathogen and stops it spreading to other people. Not every infection needs treatment, such as aa common cold, and getting the treatment right is important: for example, antibiotics won’t help you with the flu.
Bacterial pathogens can become resistant to the antibiotic treatments we give them if that treatment doesn’t fully kill off all the pathogen in a person. These resistant bugs can then be transmitted to others, meaning the treatment also won’t work on them. This limits our options for killing off pathogens and stopping them spreading. So, ensuring antibiotic resistance doesn’t happen takes collective responsibility and action.
With some infectious diseases on the rise in parts of the UK, what should the public know about how they are transmitted and prevented?
It can be tough to keep up with what feels like a new outbreak every month. It’s important to remember that most respiratory diseases transmit in a similar way to what we saw with COVID-19, so mask wearing and hand washing during peak season can still be effective.
Prevention is always better than treatment, so vaccination where possible and keeping yourself overall healthy in terms of nutrition and lifestyle can go a long way towards stopping the spread of infectious diseases. The NHS and UKHSA have great fact sheets on different pathogens which can help you keep up to date on the best way to prevent getting infected.
Conor is an Associate Professor in Microbial Bioinformatics at NTU's School of Science and Technology, specialising in the molecular epidemiology of bacterial pathogens and the evolution of microbiomes. He is a member of the Royal Society of Biology and a Fellow of the Higher Education Authority.
Through challenging the status quo, NTU researchers reframe how we see the world and tackle the big questions shaping society