It is happening more and more that antibiotics do not work against pathogenic bacteria and fungi. Doctors and microbiologists are even talking about a new 'silent' pandemic, which is killing hundreds of thousands of people worldwide.

The World Health Organization (WHO) is calling attention to this  during World Antibiotic Resistance Week from November 18 to 24. Professor Constance Schultsz researches antimicrobial resistance and emerging infectious diseases: "There are ICUs outside the Netherlands where bacteria are even untreatable."

Every year, an estimated 700,000 people worldwide - mostly children and the elderly - die from sepsis (blood poisoning), pneumonia and tuberculosis caused by bacteria that common antibiotics cannot control. The majority live in low- and middle-income countries. The United Nations predicts that in the next three decades the number of deaths from infectious diseases against which antibiotics no longer work will rise sharply: to more than 10 million annually.

The Netherlands is still doing quite well
"Most people don't see this and don't notice it," says Constance Schultsz, who is affiliated with Amsterdam UMC and the Amsterdam Institute for Global Health & Development (AIGHD). For some bacteria, the situation is improving in certain European countries. Such as with the notorious "hospital bacteria" MRSA, which is resistant to common antibiotics and appears especially in places where many antibiotics are administered. "Hospitals have taken measures to keep MRSA out. But for other bacteria, you actually see increasing resistance in Europe."

The Netherlands is still doing quite well, Schultsz explains, "Because we do infection prevention, adhere to the rules for antibiotic use - such as not prescribing anything for a nose cold - and because we can only get antibiotics on prescription. But even here, for example in people with urinary tract infections, doctors see that resistance is starting to become a problem. Intensive care units also have problems with bacteria that various antibiotics cannot get a hold of. There are ICUs outside the Netherlands where bacteria are even untreatable."

Poor view of extent of problem
"What the situation is in the rest of the world, especially in low- and middle-income countries, we don't know exactly," the professor continues. "We have a poor view of the extent of the problem." With her research, she is trying to change that. "Why the situation in those countries is also relevant to us? You can bring such a resistant bacterium home from your vacation address, to name but one example." How easy that is to do is shown in a 2017 survey of healthy Dutch travelers. Almost 90 percent of those who visited India came back with a bacterium that produces an enzyme (ESBL) that breaks down antibiotics.

Detecting resistance
Better data on resistance in poorer regions also contribute to the different use of antibiotics in these countries. If you know which drugs no longer help against a particular infection, then you can prescribe more specifically. That is why the OASIS project was started a few years ago. This is an initiative of the AIGHD and research institutions from France, Germany and the African countries Togo and Burkina Faso. They developed a so-called 'surveillance strategy' with which you can determine more quickly and more efficiently how often resistance occurs somewhere. Good results have been achieved in Indonesia. Currently the method is being tested in Togo and Burkina Faso. Schultsz: "Together with the German 'RIVM-for-animals' we want to see whether we can measure resistance in animals more efficiently with this method. Meanwhile, the WHO is also interested."

To reduce resistance worldwide, the AIGHD has entered into a public-private partnership: AMR Global, with Schultsz as chair of the steering committee. AMR Global has an ambitious vision: everyone who needs it should have access to effective and affordable antibiotics.

Behavior of bacteria
To properly combat pathogenic bacteria, knowledge is needed about their behavior. How do they spread? Which genes of a bacterium cause it to become resistant to a particular drug? Can this resistance easily pass from animal to human and vice versa from human to animal? Schultsz investigated this in the case of E. coli, a bacterium that is naturally found in our intestines. This microorganism has a nasty trait, the professor explains: "It is able to pass on its resistance to antibiotics to conspecifics that were not yet resistant." Important information, although you can't do much with it yet in practice. "In theory, you could develop drugs that switch off the genes involved. But we're not that far yet."