Antimicrobial resistance threat: AVA tightens watch on use of drugs in livestock

LOUISA TANG Today Online 12 Nov 17;

SINGAPORE — Over the past three years, fewer than 800 — or 1.5 per cent of the total — food product samples failed food safety standards on average each year, such as exceeding the maximum levels of drug residues including antibiotics.

Responding to TODAY's queries, the Agri-Veterinary Authority of Singapore (AVA) said that enforcement actions were taken upon detection of such cases. It added that it is strengthening its regulatory framework on the veterinary use of human therapeutic products, such as antibiotics, hormones and insulin. These products are registered for human use and treatment, but can also be used in animals.

The agency is also looking to implement a veterinary drug registration system, and require veterinary prescription for all veterinary antimicrobials, including those used in livestock and aquaculture.

Based on its annual reports, the AVA tested about 53,540 samples in the 2016/2017 financial year, 55,160 in FY2015/2016 and 51,930 in FY2014/2015.

Globally, there is growing concern about a post-antibiotic era where people could die from simple infections, known as antimicrobial resistance. Earlier this month, Singapore launched its national strategic action plan to tackle the problem.

Antimicrobial resistance occurs when disease-causing microbes, such as bacteria, viruses or parasites, grow resistant to the effects of medicine that used to be able to kill them.

Currently, farmers are allowed to administer antimicrobials to their animals without a veterinary prescription, the action plan document stated. However, the AVA has in place licensing conditions for the manufacture of animal feed, and has issued directives to farms to ban the use of certain antimicrobials in food-producing animals.

The AVA told TODAY it monitors the use of antibiotics and other veterinary drugs through veterinary drug wholesalers’ records of sales to farms and vet clinics. It has also banned the use of certain antibiotics in food-producing animals, as well as the use of antibiotics for promoting growth of animals.

Farmers who use antibiotics in their animals need to observe a minimum withdrawal period, which ranges from a few days to several weeks, before the animals or its products can be slaughtered or sold. This is to ensure the antibiotics completely pass out of the animals’ systems, and any left are at “trace levels below maximum residue levels”.

In order to reduce the use of veterinary drugs in animals raised locally for produce, the AVA works with local farmers to to implement good animal husbandry practices, such as vaccinations.

Currently, three out of five poultry farms and six out of 118 fish farms in Singapore are certified under the AVA’s Singapore Quality Egg Scheme and Good Aquaculture Practices for Food Fish scheme, respectively. These farms are subject to stringent inspections, including the checking of farm records for vaccinations, feed and antibiotics used.

In terms of imported food, the AVA regularly tests samples for a wide range of food hazards such as pesticide residues and drug residues such as antibiotics, as well as microbial contaminants such as salmonella.

“We recognise that antibiotics are necessary for the treatment of bacterial infections in animals and when used appropriately, contributes to the health of animals. To this end, AVA advises local farmers to use antibiotics prudently,” the AVA added.

For the general public, they should practise food safety habits, as food can be contaminated anywhere along the food chain, the AVA said. Meats should be thoroughly cooked to eliminate harmful bacteria, for instance.

Experts have said the excessive or improper use of antibiotics in food production is a key factor in antimicrobial resistance. For example, if livestock receive antibiotics and develop resistant bacteria in their gut, the bacteria can spread to people who eat improperly-handled food produced from such livestock.

Most people, including many health professionals, believe that hospitals and other healthcare institutions are the main generators and amplifiers of antimicrobial resistance, noted infectious disease experts Associate Professor Hsu Li Yang and Professor Paul Tambyah in a commentary for TODAY, which was published on Tuesday (Nov 7).

However, “the volume of antibiotic use in agriculture and animal husbandry far exceeds that in humans”, they added.

The World Health Organisation (WHO) recently urged farmers to stop using antibiotics to boost growth and prevent diseases in healthy animals.

In some countries, the animal sector accounts for around 80 per cent of the total consumption of medically important antibiotics, according to the WHO.