Half of children in the UK were now resistant to some of the most common antibiotics, as fears mount that future treatment could be rendered ''ineffective'' according to a major study.
Bristol University and Imperial College London researchers studied levels of resistance in urinary tract infections caused by E.coli – a bacteria known to cause four out of five such infections.
The global research analysed 58 previous studies, which considered 77,783 cases of UTIs from 26 across the world, including the UK. The study found that many of the most commonly prescribed antibiotics had high levels of resistance.
Within western countries, more than half of all samples showed resistance to ampicillin, along with almost a quarter to trimethoprim and three in 10 to co-trimoxazole.
Children who are the most common consumers of antibiotics and routine use in early had been shown to up the risk that drugs would not work in adulthood.
Studies had suggested that antibiotics in adults might fail due to superbugs.
''Prevalence of resistance to commonly prescribed antibiotics in primary care in children with urinary tract infections cased by E Coli is high, particularly in countries outside the OECD.
This could render some antibiotics ineffective as first-line treatments for urinary tract infection,'' according to a Bristol PhD researcher Ashley Bryce and colleagues.
They say GPs were to blame, as they were prescribing antibiotics to children too often.
''Routine use of antibiotics in primary care contributes to antimicrobial resistance in children, which can persist for up to six months after treatment,'' they add, in a paper published in BMJ.
Their conclusions are based on an analysis of 58 previous studies looking at 77,783 cases of UTIs in 26 countries, including the UK, which were linked to the bacteria.
According to NHS UTIs were ''a relatively common infection during childhood''. It had been estimated that about one in 10 girls and one in 30 boys had had a UTI by the time they turned 16.
According to NHS figures, about 5 per cent of children who visited a GP when they became acutely unwell had a UTI and around 40 per cent of them are given up to three different prescriptions for antibiotics.