For hundreds of years, people have flocked to a churchyard in a small village in Northern Ireland to gather handfuls of soil known for its healing properties.
Locals believe wrapping dirt from the Sacred Heart Church in Boho, County Fermanagh, in a cloth and applying it to the skin can cure ailments, from toothache to throat infections.
And, in 2018, when scientists ran checks on the soil, they found something extraordinary.
It contained a previously undiscovered strain of a family of bacteria called Streptomyces.
Many bacteria naturally produce ‘home-made’ antibiotics to attack other bugs competing for resources – but Streptomyces are among the most prolific.
Because of this, scientists have been using previously discovered strains for decades to produce antibiotics, such as erythromycin (used to treat everything from chest infections to acne).
But when scientists tested the new strain of Streptomyces, they found it produced a compound that was able to kill bacteria that had become resistant to existing antibiotics – raising hopes that it could ultimately help combat antibiotic resistance.
Resistance has emerged because of overuse – and misuse – in medicine and farming. The World Health Organisation calls it ‘one of the biggest threats to global health today’.
Locals believe wrapping dirt from the Sacred Heart Church in Boho, County Fermanagh, in a cloth and applying it to the skin can cure ailments, from toothache to throat infections
The resistant bugs the new antibiotic were able to destroy included both MRSA and those already immune to vancomycin, widely regarded as the antibiotic of last resort.
Dr Gerry Quinn, a microbiologist at the University of Ulster, and one of the team which found the new antibiotic lurking in the soil, says the bacteria that produce it – which researchers named Streptomyces sp. myrophorea – is common in the limestone hills surrounding the churchyard in Boho. Its presence here and in other limestone-rich areas of the world, he believes, may partly explain why certain sites of religious significance spring up where they do.
Dr Quinn told Good Health: ‘Even if you look at places like Lourdes [a Catholic pilgrimage site in France, where the water is said to have healing properties] or Medjugorje [a similar site in Bosnia and Herzegovina], the same kind of geology exists where you can find these organisms.’
In a paper published in the Journal of Religion and Health earlier this year, Dr Quinn cites numerous examples where, according to folklore, soil is believed to have powerful infection-fighting qualities – he is convinced that such locations could be a goldmine in the search for new medicines.
And potential new antibiotics are being uncovered in other unlikely places.
Scientists at McMaster University in Canada revealed in April that they had found a possible candidate in the back garden of one of the researchers.
Called lariocidin, it was cultivated from a soil sample that contained bacteria called paenibacillus, which can trigger urinary and skin infections and endocarditis (inflammation of the inner lining of the heart), reported the journal Nature.
What made lariocidin so exciting was that it had a completely different mode of action from most antibiotics – which usually attack the wall or coating surrounding the bacteria.
Dr Gerry Quinn, a microbiologist at the University of Ulster, believes organisms within some soil types may partly explain why certain sites of religious significance spring up where they do
Lariocidin instead binds to a receptor on the bacteria and stops it from reading its own genetic instructions on how to survive and reproduce – killing it rapidly. In tests, lariocidin destroyed a bug called mycobacteria, which causes tuberculosis.
The McMaster team are now looking at how lariocidin might be developed into a medicine.
Many drug companies have pulled out of antibiotic research because of the difficulties they face developing drugs that won’t rapidly become ineffective due to resistance – costing them money.
But if bacteria can so easily become resistant to antibiotic drugs used in humans, why doesn’t the same happen when they encounter natural antibiotics in the ground or in water?
The answer, says Paul Dyson, a professor of molecular microbiology at Swansea University, is that ‘bacteria in soil are constantly exposed to a range of different antibiotics produced by rival organisms. They might in theory evolve resistance to one of those but they don’t stand a chance fighting off all of them.’
He adds: ‘Yet in medicine we usually only treat patients with one single antibiotic at a time.
‘If we routinely gave all patients two different antibiotics instead of one, it would mean the bacteria would have to evolve resistance to both – which is much less likely to happen.’
Rather than increase resistance, this strategy would, he believes, reduce the problem.
In a 2021 study at Emory University in the US, scientists tested two antibiotics together – streptomycin and nalidixic acid – against E.coli, and found the bug was less likely to develop resistance when the drugs were given in combination, rather than individually, reported the journal PNAS.
Meanwhile, Dr Quinn says: ‘We are reaching a crisis in antibiotic therapy. But I’m confident that exploring how these antibiotics work in their natural environment in the soil will help us to crack the drug resistance problem.’
… and check your bird bath for clues too!Â
Several initiatives aimed at discovering new antibiotics lurking in the soil or water are utilising the help of the British public.
One called Antibiotics Unearthed, encourages people to collect soil samples from different locations (such as forests), which are then tested for potential new antibiotics by scientists in the lab.
A similar scheme – Citizen Phage – is recruiting volunteers to collect water samples from rivers, bird baths and garden ponds to be tested for the presence of phages (viruses capable of destroying bacteria).
Researchers at Exeter University, writing in the journal Microorganisms last year, described how water samples sent in by the public produced new phages capable of destroying Klebsiella pneumoniae – a common cause of urinary tract and chest infections and a bug that is increasingly becoming resistant to antibiotics.