Are animals to blame for peak antibiotics?

How signing the TPPA and buying New Zealand meat could help the fight against our growing resistance to antibiotics

'Peak Antibiotics' is a catchy headline. Prime TV ran a documentary with that title just this month. Whether that turns out to be a true depiction of this era will depend on changes to policies around their use and regulations surrounding their development.

The big, global problem beneath the headline is that the path to release for a new antibiotic is long and expensive. suggests that pharmaceutical companies spend an average of US$5 billion in research and testing for each new drug they bring to market. These costs cover the approximately 80% of drugs which fail during the testing process (safety or efficacy). The European Observatory on Health systems and policies estimates that large pharmaceutical companies need annual sales of up to US$800 million to recoup research and development costs. Although smaller companies might need only US$100 million to cover investments, they also rely on larger companies to buy their successful drugs.

The overall result is that pharmaceutical companies find it more lucrative to concentrate on drugs that can be used regularly without losing effectiveness, such as antidepressants, statins, and anti-inflammatory medications, than take the risk and expense in developing new drugs. As a consequence, many pharmaceutical companies have ceased research on antibiotics.  

Responding to concerns, the US Congress approved the Generating Antibiotic Incentives Now (GAIN) Act in 2012.  The Act was designed to help companies with antibiotic research and development. It created the Antibacterial Drug Development Task Force, fast-tracks the FDA-approval process, and requires the FDA to provide updated trial guidance. It also extended drug-patent exclusivity for an additional five years. 

The TPPA has agreed with the patent protection: the consequences of not doing so are that drugs will not be available in New Zealand when needed. 

Antibiotic resistance and the Trans Pacific Partnership Agreement are linked. New Zealand is integrated with the rest of the world as a result of interchange of world views, products, ideas and ‘other aspects of culture’.  Further, antibiotic resistance affects New Zealanders whether or not we have played a significant part in creating the problem. 

At the beginning of this month, five patients admitted to Dunedin Hospital were reported to have screened positive for an antibiotic resistant bacteria, known as vancomycin-resistant enterococcus (VRE). 

This news has built on concerns raised at the end of last year when Chinese researchers reported that resistance had been found to colistin, the ‘last resort’ antibiotic. The authors of the report suggested that the cause was likely to be ‘overuse in farm animals’. 

But not in New Zealand; research published in the New Zealand Veterinary Journal in March indicated that New Zealand farmers are very low users of antibiotics.  

In an examination of 26 EU and EEA countries in 2012, lead author Dr Eric Hillerton calculated that the estimated usage of antimicrobials in food producing animals varied from 3.8 mg active ingredient/kg biomass in Norway to 341 in Italy. New Zealand’s usage that year was 9.4, third after Iceland (a country not known for its large animal population). 

A report by PWC to the New Zealand Veterinary Association (NZVA) last year stated that “This level of use reflects regulation, control by veterinarians of prescribing and authorisation practices and how antibiotics are dispensed, and the country’s extensive agricultural systems.”

Dairy cows, for instance, make up half the animal biomass in New Zealand, but account for less than 40% of antibiotic use - even though large dairy cows require large doses of antibiotics when treatment is necessary. Mastitis in the national milking herd of just over 5 million cows is a constant concern for dairy farmers, but the incidence of mastitis is approximately 20 cases per 100 cows a year: the USA has 30, and the UK, 45.  

Although 60-70% of antibiotic use in New Zealand is in animals (including intensively farmed chickens and pigs and extensively farmed cattle and sheep) leaving ‘only’ 30-40% of antibiotics used in humans…. there are fewer people than cows and individuals weigh considerably less than a dairy cow. 

Dr Hillerton and colleagues calculated that the usage of antimicrobials for human health in New Zealand in 2012 was estimated at 121 mg active ingredient/kg biomass. Of the countries compared, New Zealand ranked sixteenth. 

This suggests that use in humans was 12.9 times the use in animals. 

University of Auckland researcher Dr Mark Thomas has stated that ‘antibiotic use in New Zealand in recent years is comparable with those countries considered to have profligate levels of antibiotic use, and so have high levels of antibiotic resistance’. 

He has reported that in the seven years from 2005 to 2012, annual per capita antibiotic consumption by community-based patients in New Zealand increased by 43% - an average of 6% a year. 

Dr Thomas’s research included the recommendation that The Ministry of Health increases efforts to reduce antibiotic consumption in New Zealand by setting reduction targets and then reporting on progress towards these by each of the country’s District Health Boards.

Of note is that the Ministry of Health’s list of causes of antimicrobial resistance does not include antibiotic use in farm animals:

  • Taking antibiotics for the wrong reason. The common cold and the flu are caused by viruses.  Antibiotics are not effective against viruses.
  • Not finishing a course of treatment, which can lead to resistance to certain medicines.
  • Some micro-organisms that cause infection survive exposure to the medicine (antimicrobial) that would normally kill them or stop their growth.
  • Poor infection prevention and control practice, such as not washing hands.

Dr Thomas has stated that New Zealand has relatively effective treatment for most infections due to antibiotic-resistant bacteria, although there can be disadvantages regarding cost, convenience or adverse effects. The overall picture, however, is captured by the World Health Organization: the world is in “a race against time to develop new antibiotics”. 

Patent protection will enable the pharmaceutical companies to recoup their costs of development. If the TPPA goes ahead, New Zealand will agree to that protection.  

The TPPA also means access to the markets where people are prepared to pay a premium for free-range, pasture-fed, antibiotic and growth-hormone free animal protein.  

The NZVA has the vision that ‘by 2030 New Zealand Inc. will not need antibiotics for the maintenance of animal health and wellness’. Scientific research, innovation and adoption will be required, but achieving the NZVA vision puts New Zealand in the premium market and the returns will benefit everybody.  

Dr Thomas has made a similar statement for the human side of the equation: “Sustained reductions in antibiotic use in New Zealand in the coming years will need recognition that this is a goal with major long term benefits – effort expended now is more than repaid in the future.”  

And any New Zealander concerned about the use of antibiotics in farm animals should ensure that they purchase New Zealand meat rather than that from overseas. Over half of all pork products and an increasing amount of red meat, is brought in from other countries – and is often cheaper in the supermarkets than home grown. Money saved on not taking antibiotics for a cold could be spent on supporting New Zealand farmers, and almost everybody would be better off… the drug companies are getting their break in America. New antibiotics are under development. The first new antibiotic to be discovered in nearly 30 years was hailed last year as a ‘paradigm shift’ in the fight against the growing resistance to drugs. A team from Northeastern University in Boston reported in Nature that Teixobactinshowed promise in ‘vanquishing’ drug resistant pathogens.  

Peak antibiotics is more than a catchy headline – it is a problem that should be taken seriously – but just like Malthus predictions of peak food, it could be that scientific research will push the problem ‘peak’ into the future.