As a doctor, you can sometimes tackle illnesses better when you work outside a hospital, according to Paul Mertens. But in such cases, you really have to understand what’s going on.
It all began with a simple telephone call at the start of the eighties. Paul Mertens who, at the time, was working for GGD Midden-Limburg (the regional health service for central Limburg) was called by a primary school doctor from Heel, a village close to Roermond. The message: there is a great deal of coughing in the classrooms. A small school with only one hundred and twenty-five pupils. No-one knew what the problem was. Children often cough, so it would have been simple for him just to have provided advice over the phone. But Mertens was wary and decided to get in his car.
For the section Science Cowboys, Geert Maarse speaks to scientists who are prepared to go slightly further than their colleagues.
Paul Mertens specialises in infectious disease control and international health, as well as tropical medicine and policy. Annually, he takes dozens of Rotterdam medical students to remote areas of Africa. At his farewell/relaunch lecture in 2013, he was appointed an Officer in the Order of Orange-Nassau.
It turned out to be an outbreak of whooping cough. Initially he was treated as a fool; after all, the children had all been vaccinated against DKTP (diphtheria, whooping cough, tetanus, and polio). However, Mertens, who had worked for years as a tropical doctor in areas where these sorts of exotic diseases were still rampant, knew he was right. He could hear it.
What does whooping cough sound like?
“It’s an extremely characteristic cough, and immediately recognisable. You could compare it to a conductor who can stand in front of an orchestra and infallibly distinguish one instrument from another and, moreover, hear each out-of-tune note. But this is hard to explain to a layperson, you need years of experience.”
To prove it, he went from door to door in the village each evening for months, until he had examined all 125 children and their families, and could determine the format of the outbreak. It became a well-known case, which eventually led to the conclusion that the effect of a vaccination slowly diminishes, and resulted in the specific and already implemented recommendation: do not only vaccinate children in their first year, but also when they’re four and start going to school.
Why is this such an important example?
“It demonstrates the significance of shoe-leather epidemiology. You have to roll up your sleeves. Like a farmer who walks among his cattle, or a fruit grower among his trees. A farmer can tell from the colour of a cow’s coat whether or not a calf is expected, while the minutest change in a trunk is enough for a fruit grower to know which pests are in his orchard”
The majority of epidemiologists are primarily involved with large-scale population screenings and datasets. In this way, links are made between residential environments and diseases. In fact, they’re more like data scientists.
“That’s the trend, yes.”
Do you think this a negative development?
“You can achieve amazing results with large cohort studies and randomised controlled trials, I’ve done that as well. However, the hypotheses for these studies has to come from somewhere. If you only work with datasets, there’s a danger that you get an incomplete picture of the reality. Take the outbreak of Mexican flu in 2009. At one point, it was determined that ten percent of sufferers were dying; huge panic. But that percentage was based on a limited dataset from one hospital. There, it was true that seven of the seventy patients had died. But that had nothing to do with the development of the illness outside the hospital. Frequently, people who contracted this flu were never even ill. If you don’t look at everything that is really going on, there is a chance that you overlook things or, alternatively, blow them up out of all proportion.”
You take medical students to developing countries, why do you do that?
“To teach them how to look at their population through truly public health glasses. In the Netherlands, young doctors often come from well-to-do families. They lead privileged lives and experience relatively little misery or hardship. That’s fine, but it means you can’t really empathise with people who live in the Schilderswijk or Rotterdam-Zuid, i.e. with people who, relatively speaking, are much more affected by illness and die younger.”
What do you miss then?
“You don’t really learn how to observe. For example, you don’t see the cause of diabetes. You don’t know what it’s like if your family is unemployed and everyone around you smokes and drinks heavily. You don’t even see this when you work as a general practitioner in Rotterdam-Zuid, because you have a different frame of reference.”
How can they learn this?
“We put students in touch with the extremes, in the poorest areas of East Africa. There, they are instructed to observe the living conditions and cultural customs of a remote village without prejudice, and I ask them: which diseases would you expect these people to contract? And – when they find themselves sitting next to a nineteen year-old girl who’s been circumcised, married off at the age of thirteen and already had six children – you can see that they suddenly get it. They understand why uterine prolapse and fistula are the order of the day in these Kenyan villages. Moreover, they realise the problem can’t simply be solved by an extra gynaecologist.”
Can you remember the moment you first ‘got it’?
“Yes, it was during my first job in Africa. I was the head of a midwifery clinic in a provincial hospital in Kenya. My first patient was a woman who was dying in hospital. When I looked at her records they were blank, no-one had examined her; even though she was as good as dead. During the examination, it emerged that she had a ruptured womb, and a dead child in her stomach. And she died of sepsis: blood poisoning. From the first day, I was, on average, operating on two ruptured wombs a day. I wondered: why’s this happening? In the Netherlands, you never see a ruptured womb. To my knowledge there’s only been one case, in Hoorn, and the doctor in question was convicted. Then I became aware that these Kenyan women had all had Caesarean sections; often when there were no medical indications for such. And: once you’ve had a Caesarean section, you usually need to give birth in this way in future, but no-one had explained that to them. This made me realise that we were simply wasting our time. I became aware that good doctors shouldn’t wait at the end of the line until patients come to them. Good doctors are, by definition, also involved with prevention.”
Do you think young doctors have adopted this attitude and ambition sufficiently?
“A quarter of all medical students take part in our minor Global Health; and the block Doctors and Public Health, during which a link to social problems is sought, is compulsory for everyone. In general, I find that students value these programmes highly. However, it’s questionable whether these days doctors can simply say: I’m promoting public health and I’m going to look into this. As far as I’m concerned, during training, more attention could still be paid to public health and social medicine. We have to make doctors more aware of their social and political responsibility. Recently, I heard from a hospital in the region that some heart surgeons were standing outside smoking. In my opinion, that’s simply not acceptable. You have a responsibility. And the misery suffered by your patients should inspire doctors to look beyond the walls of their consulting rooms.”
But public health in the Netherlands is very good, isn’t it?
“Yes it is, but we mustn’t take it for granted.”
Has our prosperity made us lax?
“Sometimes I think it has. If you’ve experienced a polio outbreak, you appreciate how important it is to fight for public health. But lots of people don’t even know anymore that you can die from measles. They choose not to have their children vaccinated because, erroneously, they think they may become autistic. But diseases can become rife again really quickly. In the last decades, we’ve had two natural experiments which have demonstrated that fact. When the wall fell, the level of vaccination in Russia plummeted and suddenly tens of thousands of children were suffering from diphtheria. And when huge numbers of people in England stopped having their children vaccinated, whooping cough resurfaced. But, unfortunately, science is all too often simply viewed as an opinion these days.”
Does this worry you?
“One of the propositions in my dissertation is: ‘Because scientific modes of thought play a central role in today’s society, politicians, judges and religious leaders should all have a good epidemiologic education.’ Currently, all sorts of things are alleged. What I object to is that people often don’t bother to ask themselves: how can I prove that something is true or not? A couple of simple lessons can explain that to someone. It should, therefore, be part of the basic knowledge taught in primary schools.”
A couple of years ago you made your farewells, but you’re still working.
“As long as I can, I’ll keep busy. I really enjoy my work.”
Vindt u het jammer dat u nooit hoogleraar geworden bent?
“Not at all. I’ve discovered that I’m not a very good manager; and I enjoy being involved in the content too much. When I came back after finishing my programme at John Hopkins, I set up a study at the Radboud University examining the relationship between neural tube birth deformities in babies and a lack of folic acid in mothers, with a view to a professorship. However, I wanted to work outside the hospital and, generally, that makes it much harder to become a professor. Field research doesn’t always result in publications which attract a lot of attention. But we absolutely couldn’t do without them.”