Researchers at the University of Hong Kong say they have found evidence that urinary tract infections are becoming drug resistant.

BBC News reports that overuse of antibiotics in the farming industry is leading to the drugs entering the food chain and fuelling the rise of drug-resistant infections.

The researchers investigated Escherichia coli bacteria (E coli), which is responsible for causing most urinary tract infections (UTIs) in humans.

The team looked at samples of bacteria from both humans and animals and discovered an identical gene in both for antibiotic resistance, known as the aacC2 gene. The gene is responsible for causing resistance to the widely-used antibiotic gentamicin and was present in around 80 per cent of the samples from both human and animal sources.

Lead researcher Dr Pak-Leung Ho said:

‘These resistance genes may possibly spread to the human gut via the food chain, through direct contact with animals or by exposure to contaminated water sources.

‘When the resistance genes end up in bacteria that cause infections in humans, the diseases will be more difficult to treat.’

The research was carried out solely in Hong Kong, but the team says that the problem is global.

‘With the international trading of meats and food animals, antibiotic resistance in one geographic area can easily become global,’ said Dr Ho.

‘Health authorities need to closely monitor the transmission of resistance between food-producing animals and humans and assess how such transfers are affecting the effectiveness of human use of antibiotics.’

An expert in bacteria at the University of Birmingham, Professor Chris Thomas, said that

doctors in the UK were also seeing drug-resistant strains of UTIs – and travelling and farming methods made the problem ‘global’.

Prof Thomas added that more expensive antibiotics could sometimes be used to treat drug-resistant UTIs, but in time these might also fail.

In the UK, it is estimated one-third of women will have had a UTI by the age of 24.

The findings of the Hong Kong study are published in the Journal of Medical Microbiology.

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