The conference, ‘Antimicrobial resistance: from farm to fork and beyond’ was organised by the British Society for Antimicrobial Chemotherapy and was held in association with the Veterinary Laboratories Agency.

In his keynote speech Professor Gary French from Guy's & St Thomas' Hospital & King's College, London told delegates: “We are faced with the potential loss of antimicrobial therapy. Effective national and international programmes of control to combat these problems are urgently needed.”

Presentations from British government scientists showed that a new, almost untreatable, type of antibiotic resistance in E. coli, known as extended-spectrum beta-lactamase (ESBL) resistance, has spread from the handful of farms on which it had been identified, to more than one in three of all dairy farms in England and Wales.

One study linked the rise of ESBL E. coli on farms to the increasing farm use of modern antibiotics classified by the WHO as critically important in human medicine.

The same study will present evidence that the unregulated sale of animals from first infected farms has increased the problem.

The conference heard that ESBL E. coli infections are increasing annually and currently affect approximately 30,000 people each year in England and Wales. They cause about 2,500 cases of blood poisoning. When blood poisoning occurs about half of all patients die within 30 days. ESBL resistance only became a significant problem in human medicine as recently as 2003, and the first case of ESBL E. coli in British farm animals was found on a cattle farm in Wales in 2004.

Despite subsequently finding ESBL E. coli on a number of other cattle and pig farms, the Soil Association said that in 2006 Defra claimed that ESBL resistance was ‘at a very low level in livestock’, and that its emergence had ‘not been a direct result of antimicrobial usage in food producing animals’.

As a result, the Soil Association says that Defra took no significant action to limit the spread of the bacteria throughout UK livestock and with the Welsh Assembly allowed the original affected farm to sell its cattle at auction to 160 different farms, despite knowing this would help spread the problem UK-wide.

A presentation at the conference shows that an estimated 59 per cent of those farms now have ESBL E. coli.

A study by the VLA found that farms which had used 3rd/4th generation cephalosporin antibiotics in the previous year were four times more likely to have ESBL E. coli than farms which had not. Data from the VMD (not presented at the conference) shows that the use of these antibiotics on farms has itself increased four-fold since 2000, the Soil Assoictaion said.

A study not being presented at the conference has shown that chickens from 57 per cent of British poultry companies carry ESBL E. coli.

In a further development, Professor John Thelfall from the Health Protection Agency (HPA) presented evidence on a highly drug-resistant strain of salmonella associated with pigs and pigmeat, which has caused human outbreaks in ten European countries, and he posed the question, ‘Is this the next multi-drug resistant epidemic European Salmonella?’ Alarmingly, this same strain has now also been found in British pigs with additional ESBL resistance.

A British government scientist said that ‘Food remains under-explored as a potential source of ESBL-producing E. coli.’, while a Dutch scientist will say that their investigations already enable them to conclude that, ‘in the Netherlands poultry has contributed to the distribution of ESBL-carrying plasmids towards humans.’

Richard Young from the Soil Association said: “There has been little public scrutiny of farm antibiotic use for over a decade, yet during that time we have seen farmers dramatically increase their use of antibiotics classified by the WHO as ‘critically important in human medicine’ and we have also seen the development of several serious antibiotic-resistant bugs in farm animals which are passing to humans on food and in other ways. It is high time that the government took this problem seriously.”

Philip Lymbery, from Compassion in World Farming, said: “The intensification of agriculture, with pigs and poultry kept in cramped, unhygienic conditions, and dairy cattle pushed harder and harder to produce more milk, has led farmers to rely on hugely important antibiotics to treat the diseases this is causing. We are now getting the evidence that this has real implications for human health too. It is high time that Defra stopped downplaying the evidence and realised that the only way to address this problem is to start keeping farm animals in more natural and less intensive ways.”