"Without effective antibiotics, the achievements of modern medicine will be lost"

Interview mit Christoph Dehio, Mikrobiologe

Medical doctors, veterinarians and environmental scientists should work together more closely to combat antibiotic resistance, says Christoph Dehio.

The problem of antibiotic-resistant bacteria is a familiar topic. Do you personally know anyone who is actually suffering from a condition caused by such bacteria?

Almost everyone knows someone who needed considerable follow-up care after a successful operation because a germ had lodged itself in the wound and triggered an infection. The media are full of tragic reports about people who were fatally infected with a pathogen resistant to a broad spectrum of antibiotics. Outcomes of this gravity tend to affect individuals with a weak immune system, such as people in intensive care. That being said, antibiotic-resistant germs can also infect patients with no pre-existing illnesses. In all these cases, there are no suitable treatment options available to doctors.

Antibiotics are still being successfully used. When do you envisage a situation where otherwise non-vulnerable individuals also become susceptible?

The scenarios for the next ten years or so are alarming. The number of multiresistant bacterial strains is increasing dramatically. Without effective antibiotics, the achievements of modern medicine will be lost: routine operations and bacterial infections that are currently readily treatable will become increasingly life-threatening. But no one can predict for certain exactly what is going to happen. Attempting to make precise projections of the timeframe would be tantamount to scaremongering.

What is the key cause of the acute worsening of the situation?

There are various causes. The broad and sometimes uncoordinated use of antibiotics in human medicine and animal husbandry inevitably leads to the appearance of multiresistant germs. Global movements of goods, animals and people accelerate the worldwide spread of problem germs. On the other hand, the industry hardly develops anymore new antibiotics. This is partly due to the limited number of potential active ingredients and the poor prospects of achieving business success with new molecules, especially given the likelihood of pathogens quickly becoming resistant to them.

Did scientists and politicians simply look on for too long?

Yes, precisely. The problem was long evident. But we clearly all underestimated how acute the situation was becoming and the speed at which it was happening, otherwise more resources would have been poured into research much sooner. Fortunately, things have changed now. Antibiotic resistance was even on the agenda of the G8 summit in 2013 in London. In 2015, the Swiss federal government launched its national antibiotic resistance strategy (StAR) and, in partnership with the Swiss National Science Foundation, our NRP 72.

How can NRP 72 help to solve the problem?

The aim of our research projects is to help develop concrete solutions within 5 years. We examine the different aspects of the resistance problem in three modules: in the first module, for example, we investigate how and where antibiotic resistance occurs, and how it is passed on from bacterium to bacterium. This is important in terms of systematically combating the further spread of antibiotic resistance.

Can research also help people who are already infected with resistant germs?

Yes, in a second module, we are developing faster methods of diagnosis. Today, it normally takes anything from one to several days to cultivate the bacterial pathogens and determine their resistance spectrums. During this time, doctors are groping in the dark as to the best treatment options. If this information were available within a matter of hours, treatment with the right antibiotic could begin at the outset. Under this module, we will also be looking for new active ingredients that the pharmaceutical industry can develop into market-ready products.

Does that mean you’ll leave the job of testing the effectiveness of new active ingredients to industry?

Developing an active ingredient through to market launch is too lengthy and costly a process to tackle under an NRP. This is why the clinical trials that we will conduct in our third module are mainly focused on the goal of reducing antibiotic consumption and minimising the spread of antibiotic-resistant germs.

Can you name any successful examples of preventive measures?

Methicillin-resistant Staphylococcus aureus (MRSA) was in the headlines a number of years ago. In response to the increasingly critical situation, the Netherlands introduced targeted screening at hospital admission. Patients identified as carriers are isolated and treated with specific measures to prevent the resistant germs from spreading. While this search and destroy policy is cost and labour-intensive, it is highly effective. Strategies of this kind are also practised in isolated instances in Switzerland, but unlike in the Netherlands, say, there are no binding guidelines in place at national level.

Aside from antibiotics, are there any other active substances that are effective against bacteria?

Certain disinfectants, but they can only inactivate germs on the body's surface. Antibiotics are by definition selectively toxic active substances. They kill bacteria without harming the human body. Alternative approaches are also available to treat bacterial infections in the body. For instance, some active ingredients, which themselves are non-toxic, can make resistant pathogens sensitive to antibiotics. The use of bacteriophages (viruses which infect bacteria) is another interesting strategy, and one that doctors in Eastern Europe have been practising for decades and was, for example, employed to treat superficial skin infections. The effectiveness of this method has yet to be verified by controlled clinical trials.

NRP 72 adopts a one-health approach. What does that mean?

Human and veterinary medical training follow divergent paths. In many respects, this makes complete sense. But when it comes to overcoming antibiotic resistance, research and treatment need to cross the boundaries between these disciplines as well as factor in the environmental sciences. Pathogens enter the environment and pass back and forth between animals and humans. This is why steps must be taken, for example, to ensure that antibiotics crucial for medical emergencies and operations are reserved for such cases and not used for outpatient treatment, to say nothing of animal husbandry. Intelligent antibiotic stewardship is called for.

There is still a great deal to be done to ensure that livestock breeders, hospital staff and the general public help to enforce such measures. Will NRP 72 be rallying the cause?

The ultimate goal of NRP 72 is to present concrete solutions. As with all NRPs, they will be addressed at policymakers and administrators with the necessary authority to implement them. However, under StAR, we will be involving representatives from the health, agricultural and environment sectors early on. This is why StAR project leader Karin Wäfler from the Federal Office of Public Health has been an observer in the NRP 72 Steering Committee right from the start.

Resistant pathogens travel the globe with their human hosts. In concrete terms, what can Switzerland do about this?

High mobility levels do indeed pose a major challenge for our healthcare sector. For example, highly resistant germs are currently spreading at great speed throughout the world from India. Clearly Switzerland is affected too, which underlines the need for rapid diagnosis and control measures at hospital admission.

What can our small country contribute to international research?

Switzerland is an outstanding research location. In the past decade, it has already developed a high degree of proficiency thanks to the National Research Programme "Antibiotic Resistance" (NRP 49). Our excellent researchers are internationally well connected. Because the international dimension of the problem is so important, part of the budget for NRP 72 has been reserved for participation in the "Joint Programming Initiative on Antimicrobial Resistance" (JPIAMR), which takes a crossborder approach to the problem at European level.

What would need to have been achieved by the time NRP 72 is concluded in five years for you to regard it as a success?

Switzerland has competent researchers, an efficient health and veterinary system and a strong pharmaceutical industry. But one thing is clear: even under the best-case scenario, we'll be facing the phenomenon of antibiotic resistance for a long time to come. If NRP 72 can develop concrete measures to win valuable time to find a more fundamental solution that would be a major step