Antimicrobial resistance is not stopped by national borders

Henrik Duesund, Head of Cermaq’s R&D fish health team

Dr. Patrik Henriksson, forsker Beijer Institute of Ecological Economics, Stockholm Universitet (Science member of Seabos)

By 2050, 10 million people could die from bacteria and other microorganisms that are resistant to antibiotics. Also, countries and regions using little antibiotics will be affected.

Antimicrobial resistance (AMR) is a global threat to human and animal health and welfare. In the World AMR Awareness WEEK (WAAW) 18-24 November WHO the World Health Organization, has chosen Preventing antimicrobial resistance together as the theme for the WAAW 2023

Norwegian salmon farming can be the best in not needing antibiotics

Norwegian animal husbandry has minimal needs for antibiotics. With salmon is included, Norwegian livestock production is among the global best because Norwegian salmon farming uses the very least amount of antibiotics. In Norway, there is culture of restrictive and responsible use of antibiotics for both animals and humans, which has resulted in very low rates of antibiotic resistance. Thus, learnings from Norway could be translated to other countries and farming systems.

Responsibility across borders

With salmon farming in several countries and parts of the world, Cermaq has special follow-up to ensure restrictive and responsible use of antibiotics throughout its business, beyond applying preventive measures such as vaccines and screening of smolts which are always used. Sick fish require follow-up, and sometimes treatment with antibiotics is necessary to ensure animal welfare. Before sick fish are given antibiotics, we check that there is no resistance, to identify the smallest effective dose. The types of antibiotics used is also important from a human health perspective. In the production of food for humans, Cermaq only uses antibiotics that are not critical for human health. We also collaborate with other companies, including through the Global Salmon Initiative (GSI) and SeaBOS, where we share our experiences, research, and test results so that our neighbors and competitors will be the best possible.

Responsibility for other species

Salmon dominates farming in a few countries, but salmon is a small part of global aquaculture*, at volumes less than both shrimp and tilapia. In some regions, there is significant use of antibiotics**, including types of antibiotics that are also used to treat humans.

Through SeaBOS, a collaboration between the largest seafood companies globally and internationally leading research institutions, Cermaq is engaged in strengthening sustainability in the seafood sector globally. Responsible and restrictive use of antibiotics is one of several areas SeaBOS works on. Based on the best practice, we have created simple and clear guidelines for the restrictive and responsible use of antibiotics. These are guidelines that can be used in all types of farming, and which will have a collective gain as more seafood producers adopt them. Only collective actions to reduce antibiotic use will reduce antibiotic resistance in our food system, so we encourage our codes of conduct and demand restrictive and responsible practices. The codes of conduct can be found at www.SeaBOS.org

Transmission from animals to humans?

The risk of emergence and flows of antibiotic resistant genes is something that SeaBOS will map together with researchers at the Stockholm Resilience center, the Beijer Institute of Ecological Economics, SAAFE CRC, and Chulalongkorn University. The research will look at shrimp farming in Thailand and aims to identify methods to determine the sources of AMR genes in shrimp (e.g., water, feed, additives, process water, surrounding ecosystem, and other). The ambition is that such knowledge will allow for more restrictive and effective use of antibiotics in ordinary operations.

Can resistant genes in bacteria in seafood be transferred to humans? There is always a risk of zonotic disease that can affect both animals and humans, and through resistant gene transfer between bacteria. Thus, the best way to reduce risk to humans is to minimize antibiotic use in animal husbandry, as it is the only way to avoid selection for resistant genes.

"There is little risk of transfer of resistant genes to humans from salmon. Salmon lives in colds waters, and salmon and humans do not have overlap of bacteria that can infect", says Henrik Duesund, R&D manager at Cermaq.

Together we can prevent AMR

We may not understand the value of antibiotics until we risk that they have lost their effectiveness. Together we can avoid AMR: everything from hand washing, better biosecurity, improved farming practices, to taking vaccines. We are not giving in; the seafood industry and all animal production must improve. Everyone can and must contribute.

* SOFIA 2022

**Global trends in antimicrobial use in aquaculture | Scientific Reports (nature.com)

About Seabos:

The SeaBOS initiative is unique because of the cross-sector collaboration within the global seafood industry. It involves nine of the world’s largest seafood companies representing over 19% of the world’s seafood production and operating in over 465 subsidiaries. Together with leading scientists across disciplines and universities, they explore transformative risks and opportunities for the global seafood industry and key impact areas.

Seabos Science Partners:

Stockholm Resilience Centre, Beijer Institute of Ecological Economies at The Royal Swedish Academy of Sciences, The Royal Swedish Academy of Sciences, Lancaster University, Center for Ocean Solutions at Stanford University and the University of Tokyo.