Science - February 14, 2019

Taming the antibiotics monster

Text:
Albert Sikkema

Ten years ago, the Dutch livestock sector was a big contributor to the emergence of antibiotic-resistant bacteria, as a big consumer of antibiotics. Now the Netherlands is leading the way in reducing antibiotic use. Researcher Dik Mevius at Wageningen Bioveterinary Research in Lelystad played a key role in that turnaround. He retired on 1 February. With peace of mind.

Text Albert Sikkema, photo Judith Jockel

When did you discover that the high rate of antibiotic use in Dutch livestock farming was a public health issue?

‘That was in March 1990, at a meeting of the Veterinary Inspectorate of the ministry of Public Health, which was the forerunner of the NVWA (Netherlands Food and Consumer Product Safety Authority). At the meeting, the Leiden microbiologist Hubert Endts presented a study that linked the use of the antibiotic enrofloxacin on poultry farms and the growing antibiotic resistance in Campylobacter bacteria in humans and chickens. A worldwide debate about that antibiotic flared up: should we ban its use in livestock?

The second eye-opener for me was a Danish report in 1995, which linked growth stimulants in livestock with VREs, intestinal bacteria that are resistant to the antibiotic vancomycin, an indispensable drug for humans. These VREs were found in a lot of farm animals. In those days, the Dutch livestock sector used 300,000 kilos of antibiotics per year as growth stimulants, adding them routinely to feed or drinking water. That could not go on. In 1998, I was on a Health Council committee, and we recommended banning the use of growth stimulants. The ban came into effect in 1999.’

Did that ban help?

‘Not really. In 1999, the livestock sector used 300 tons of growth stimulants plus 300 tons of prescription antibiotics per year. In 2007, farmers were not using growth stimulants anymore but got through 600 tons of prescription antibiotics a year. Use shifted. We had an antibiotics policy but we didn’t implement it. In practice, the economy was more important than public health. It was cheaper for livestock farmers to fight diseases with antibiotics than to prevent them with better feed and drinking water, better barns, better chains and better management. The head of the pig industry, Wyno Zwanenburg, said at the time: ‘The economy rules; I want to be able to buy cheap antibiotics, if necessary from abroad.’

Yet a turnaround did come.

‘Yes. We found more and more resistant bacteria. MRSA and ESBL became well-known abbreviations for hospital bacteria that could no longer be defeated with regular antibiotics. Hospitals started checking patients for MRSA, and there was a separate reception point for farmers. But the most important event was the outbreak of Q fever on goat farms around 2008, which cost human lives. After that, public health became priority number one, above the economy. Agriculture minister Gerda Verburg set up a taskforce, to which I was an advisor. An agreement was drawn up for each sector, aiming at responsible use of antibiotics in livestock farming. Nobody dared give figures for the required drop in antibiotic use. That changed in 2010, though, when the ANP reported: “Woman died due to chicken with ESBL.” This was on the TV news and the programme Nova, and there were questions in parliament. The ANP story later turned out to be incorrect, but it did lead to a specified reduction target: 20 per cent reduction in 2011 compared with 2009, and 50 per cent reduction in 2013.’

 Targets are not reductions, though. How was it managed?

‘The establishment in 2010 of the SDa, the veterinary medicines authority, was a very important moment. SDa, an independent institute, started analysing livestock farmers’ antibiotics use and setting goals. I became chair of the SDa’s expert group. Previously we only had the sales figures on the antibiotics, but now we had the usage figures per farm. That meant farmers could compare their use with that of others. There were farms with very low and with very high levels of antibiotic use. The registration led to raised awareness among the farmers, who set to work with vets and feed suppliers to reduce their use. They achieved a tremendous reduction in just three years. The implementation was a success due to the bottom-up approach.’

The role of vets was important too, because they prescribed the antibiotics, didn’t they?

‘The vets sold the antibiotics and made money from them. The government got Berenschot consultancy bureau to do a study on whether vets’ dispensing rights should be taken away. The conclusion then was that it wasn’t the vets but the farmers who played the most decisive role. Yet the vets made an about-turn too. The former chair of the association of vets KNKvD, Ludo Hellebrekers, gave talks to vets throughout the country in 2007. He explained that a shift was needed to a health policy. He played an important role in awareness-raising.’

The livestock sector is no longer based on the systematic use of antibiotics

Who else was important for this turnaround?

‘Christianne Bruschke, the Chief Veterinary Officer at the then ministry of Agriculture, Nature and Food Quality. She was the most important person on the government side, because she managed this dossier for years and still does. Jos Werner, the chair of the SDa, played a key role too. As CDA senator, he knew the political game in The Hague. And lastly, Toon van Hoof, chair of agriculture organization ZLTO. A man with a lot of strategic management experience who understood that it had to happen.’

And let’s not forget Dik Mevius.

‘I was on all the committees as an advisor, both the committees that analysed the development of antibiotic use and resistance, and the management committees that made recommendations on the policy to be implemented. The ‘spider in the web’? Yes, you could say that.’

Do you think we can call this a sustainable revolution in antibiotics use?

‘Yes. The livestock sector is no longer based on the systematic use of antibiotics, but is doing more and more health management. Livestock farmers now look at the quality of the feed, the barn and the drinking water, and they carry out hygiene measures. The use of antibiotics in the livestock sector has gone down by 64 per cent and antibiotics resistance in the animals is going down too. I look back on my work here in Lelystad with satisfaction.’


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