Juan Carrique-Mas: Antimicrobial resistance in poultry production
Many households in Vietnam raise animals for food production, particularly chickens, using large amounts of antimicrobials with no veterinary support, and those antimicrobials find their way into the food chain. The ViParc project conducts intervention trials similar to human clinical trials, to help farmers reduce the level of antimicrobials used when raising chickens.
My name is Juan Carrique-Mas, I am based at Oxford University Clinical Research Unit in Ho Chi Minh City in Vietnam. I am currently funded by the Wellcome Trust to carry out a large-scale field intervention to help farmers in the Mekong Delta of Vietnam to reduce their reliance on antimicrobials to produce chickens.
Antimicrobial use and antimicrobial resistance is a considerable problem in animal production, not only in human medicine, and this has been realised only very recently. It is a big problem because farmers use a large amount of antimicrobials to raise the chicks and the chickens, because they basically have no technical support from the veterinary system. It is also a problem because most of these small-scale farms have virtually no bio-security, that is almost no separation between the farming space and the household space. That means that there is a lot of exposure in these communities to the animals they are raising. It’s been estimated that approximately half of the population across the country would raise some form of food animal that can be from a few chickens to several hundred chickens, pigs, ducks etc. Overall in terms of households the census speaks about between 8 and 10 million animal raising households.
Antimicrobial resistance is indeed what we call these days a one-health-issue; we cannot just look at humans or animals or the environment, everything is interconnected. In the case of antimicrobial use in animal production, it is quite clear that there can be transmission of resistant bacteria which are pathogenic to the humans causing disease in those humans through contact, but also indirectly through the consumption of food from these animals: contaminated meat, milk, eggs and so on. Furthermore those resistant bacteria can spread into the environment and contaminate water streams, rivers, crops, and end up in our food as well even though we are not directly raising those animals.
The ViParc Project stands for Vietnamese Platform for Antimicrobial Reductions in Chicken production. I also tell people that the ‘Vi’ stands for Veterinary Intervention because we are trialling an intervention system to help farmers reduce their levels of antimicrobials in raising their chickens. It is very much focused on small scale production systems, we are not looking at the industrial, integrated farms, which are still relatively few, but on the medium and the small scale farmer. What we are doing here is very much like a clinical trial in human medicine, where we have an observation phase and then we randomly allocate two interventions and one control. One novelty of the ViParc Project compared to the other research projects is that we have included a strong, socioeconomic component because we realise that farms are businesses. If we don’t consider them to be running their own business, if we just look at it from a health perspective only, we will not be able to have an impact on them.
What is really challenging about the Vietnamese Mekong Delta situation is that farms are much more complex than we envisaged. Every farmer does things in a slightly different way, and that presents problems because we cannot design an intervention that fits all. That’s why the intervention has to be tailor-made, every farmer will be approached and will be advised on the specific problems on their farms.
I believe that the type of research that I am currently conducting, which is an intervention trial, is very relevant and very necessary. There is a lack of intervention studies that look at the important issue of antimicrobial use and resistance in animal production. Most of their studies are observational, and very few of them attempt to do something at a large scale. But I also feel that my study, my intervention is quite representative of other production systems and even for other countries that conduct similar types of farming to Vietnam.