You are a doctor of internal medicine, epidemiologist and professor of travel medicine. However, you originally trained as a flight surgeon in the Swiss Air Force. Did you always want to be a doctor, and what made you change direction?

No, I didn't always want to be a doctor. At first I thought I wanted a quiet profession. I found chemistry interesting. Then I thought about becoming a dentist because I thought I would be able to master this limited field of knowledge intellectually. During the second propaedeutic exam, however, the examiner persuaded me to become a doctor. After a week at the dental institute, where I had to shape a plaster tooth, I finally realized that I was not at all gifted in manual skills. So after a week, I switched to medicine.

So you wouldn't have become a surgeon either.

No, not at all (laughs).

And how did you come to join the aeromedical service?

I have always been fascinated by flying and traveling. I have been interested in the whole world since I was a child and I was enthusiastic about studying abroad as an exchange student. In the medical student organizations, I first became responsible for student exchanges in Zurich, then for Switzerland and finally for the whole world. In the end, I was president of the international medical student associations. That meant I had to visit the member countries. As a junior doctor at the Aeromedical Institute, I was able to negotiate a deal with the chief physician: if I stayed for two years instead of just one, I was allowed to go on longer trips abroad in between.

So you had already traveled quite a bit around the world. How did you get into travel medicine afterwards?

For the many trips to South America, Africa and Asia, there were still no guidelines as to how to protect oneself. The books on tropical medicine at the time contained different and contradictory vaccination recommendations. I was also vaccinated against the plague back then.

That's why it remained in the back of my mind that this should actually be scientifically investigated in order to obtain evidence about what was really necessary and what priorities should be set. So I started to take an interest in travel medicine. However, it was only at the beginning of the 1970s that I started to set up "hand-knitted" epidemiological studies with a few colleagues.

Today you are regarded worldwide as the "father of travel medicine". One of the reasons for this is that you set up the first international conference on travel medicine in 1988, here in Zurich at ETH. Can you tell us how it came about? Who was there?

That was many encounters and years later. To explain this, I need to expand a little. First of all, travel medicine had to be established here.

In the mid-1970s - I was the first senior physician in internal medicine at Zollikerberg Hospital at the time - I was offered a position as chief physician at a smaller hospital and I asked myself "Is that it?". I decided to turn it down and accept a fellowship at the University of California in San Francisco instead.

When I returned to Switzerland, nobody was really interested in travel medicine. I had knocked on the door of Meinrad Schär^[2],  the head of the Institute of Social and Preventive Medicine at the time, and he said it wasn't really necessary. And so, somewhat frustrated, I opened my own practice in Küsnacht in 1978.

Almost 3 years later, I received a call from Prof. Schär, who offered me a 50% position as head of the vaccination center (as it was called at the time). Of course, I gratefully accepted and built up the travel medicine department over the following years.

And you organized the first international conference on travel medicine with this team?

No, there was an incident that you may be aware of. In the past, other drugs were used for malaria prophylaxis, including FANSIDAR®, which contains a sulphonamide (sulphadoxine) and this occasionally led to very severe skin side effects. Roche contacted me to participate in a hearing to discuss this problem. A Dutch malariologist from the CDC^[3]  Dr. Hans Lobel^[4]  was present. We quickly found out that we were both interested in keeping travelers healthy, and so we started doing malaria research together. At the same time, I was speaking at a gastroenterology congress in Stockholm on the subject of traveler's diarrhea. An American approached me and said he would like to work with me as we were the first to have data on this. That was Herbert DuPont^[5],  who we later awarded an honorary doctorate here in Zurich for the collaboration and his pioneering research in the field of gastrointestinal infections. These were my two main partners. Of course, I also collaborated with many other colleagues, including the WHO^[6]  early on.

Hans Lobel suggested one day that it would be useful to organize a congress on travel medicine in order to achieve a global assessment of the situation and that Switzerland would be an attractive venue. And so I organized the first international congress for travel medicine.

Initially, we didn't even have a name for "this child". We wondered whether it should be called "Tourism Medicine" because there was a booklet with that title from Germany. In France, the term "emporiatry" was floating around. It came from the Greek and referred to the rear part of the ship where the passengers were located. But we found that nobody understood this elitist term. At some point, we decided on the term "travel medicine", which could also be easily translated into other languages.

So you gave this medical field its name?

Exactly. We didn't even know how many people would come to this congress.

How many people did come?

We hoped to be able to welcome at least a few dozen people, but in the end there were around 500 participants. There was a very good atmosphere because we were finally able to exchange ideas. Other countries had also started to conduct travel medicine research with limited resources, but we were the first to systematically and broadly record health problems. This was based on a study of over 10,000 tropical tourists and a control group of travelers returning from North America. It was finally decided that there should be a next conference. This was organized by Dr. Hans Lobel and Prof. Phyllis Kozarsky^[7] in Atlanta, took place in 1991 and was attended by around 800-900 people.  The International Society for Travel Medicine^[8] was founded there.

Who spoke at the first congress?

The keynote speech was presented by Prof. David Bradley^[9]. He described the necessity of travel medicine based on a historical comparison. His great-grandparents were still traveling in horse-drawn carriages in the north of London, while he was an eminent malaria researcher and traveled around the world. He showed that travel medicine is needed because more and more people are traveling further and more often than ever before.

There were also various speakers from the WHO, although the WHO was somewhat divided, as travel medicine was considered "luxury medicine" in this environment, and the WHO saw itself more as serving the "needier" population groups in low and middle income countries^[10]. Nevertheless, the WHO showed interest from the outset.

Luxury medicine? Is it?

No, certainly not only, we also advise backpackers. The square circle here is that a particularly large number of measures, such as vaccinations, would be indicated for them if the budget is tight. In addition, the longer we work with migrants, the more we deal with them. Thanks to the GeoSentinel network, travelers are also so-called "sentinels" and thanks to this international cooperation, we may even be able to find out more quickly if an epidemiological problem occurs in a developing country because the health authorities there often lack diagnostic capabilities.

If you compare travel medicine today and in the past, what has fundamentally changed?

As I have already described, as a student I was almost flying blind when it came to health, as there were only contradictory recommendations. A little later, three main areas of travel medicine emerged, which we also actively researched in Zurich. The first focus was on vaccinations, particularly with regard to the question of priorities. Secondly, malaria was very important, as we realized that we were losing many lives here. There were one or two deaths from malaria in Switzerland almost every year. The third accent that particularly interested me was traveler's diarrhea.

Gradually, we realized that in terms of mortality, other risks are much more relevant abroad. It is accidents in particular that cost the most lives among travelers. These include not only traffic accidents, but also sports accidents, such as mountaineering or swimming. It quickly became clear that we needed to educate and warn travelers about this.

Another topic that interested me early on was sexually transmitted diseases. There was hardly any talk about it at the beginning, but that was at a time when there were an increasing number of HIV cases with a high mortality rate. Today you can live well with it under therapy. We have also conducted several studies on this.

There were of course many other interesting topics. I once made myself particularly popular with the staff when I carried out a whale safari study in Norway. Many of the institute's employees were allowed to go to Norway for two weeks to recruit volunteers who had booked a whale safari. They were given various medications for seasickness to determine which was the most suitable. We knew from the captain that without prophylaxis, 80% of the passengers fell ill.

This led to more and more fields being researched, which were ultimately also addressed in travel advice. An important keyword here is certainly acute mountain sickness and high-altitude medicine. We worked with an expert from Triemli Hospital on this: Professor Oswald Oelz^[11]. The NZZ has just conducted an interview with him^[12].

Thanks to digitalization, the current generation of researchers has opportunities that I somewhat envy. I am particularly fascinated by how the state of mind of our customers can now be recorded on the move. Apparently, a variety of problems that we have neglected so far are causing difficulties. These often seem trivial, but they are very important for the quality of life abroad.

You have studied and worked in many countries. What does travel medicine look like in other parts of the world?

Initially, there were discussions around the world as to where travel medicine belonged. Does it belong in tropical medicine? Is it part of infectiology? Is it independent? I have always emphasized that travel medicine is interdisciplinary. Think, for example, of advice for pregnant women, infants, the chronically ill and immunosuppressed. When it comes to high-altitude medicine or diving, we are back in the domain of general internal medicine, physiology and ENT. That's why I found that travel medicine is a separate but very interdisciplinary medical field.

The longer the travel period, the more congruent the recommendations for travelers in industrialized nations, based on evidence from epidemiological studies. Differences are often due to the fact that the same range of vaccines or drugs for prophylaxis and therapy are not available on the market everywhere. However, there are still differences: in the USA, for example, the vaccine against abdominal typhus is the one that is administered most frequently. In Japan, it will take a few more years before preventive measures are as important as they are here.

So tropical medicine is part of travel medicine and not the other way around?

It goes without saying that tropical and travel medicine should work together, but they should be on an equal footing. Travel medicine should not have to sail under the umbrella of tropical medicine.

All right, and with all this experience and knowledge under your belt, did you create the Travel Clinic UZH from the "vaccination center" that Mr. Schär appointed you to head?

Exactly. At that time, the vaccination center primarily carried out smallpox vaccinations, which were still necessary for all trips to the USA and many other destinations. When I started there in 1981, things slowly changed. We were increasingly consulted by travelers who had previously received a smallpox vaccination from us and wanted to find out about vaccinations for a new trip.

When I started work, the doctors gave vaccinations and the administrative staff carried out the consultations and decided which vaccinations should be given. Within two weeks, I turned that around by making the doctors do the intellectual work of reading up and being informed. We had a "nurse" (DE: "Krankenschwester), as they were still called back then, and a secretary who we trained and who could also vaccinate. These two vaccinated.

In the beginning, we had two offices at Gloriastrasse 30 and people queued up on the stairs, which was not at all customer-friendly. That's why we looked around for another location. Around 1984, we moved to Sumatrastrasse 30 and we moved to Hirschengraben 84 around the year 2000, because together with the director of the institute at the time, Prof. Felix Gutzwiller^[13], I thought this was the ideal address for us.

In fact, our location is very much appreciated. Before the pandemic, we only had walk-ins. Has it always been like this? Why were no appointments made here?

Yes, the decision to use a walk-in clinic was purely pragmatic. We never had staff to make appointments by telephone. There were no electronic options yet. The waiting times were often up to 2 hours, which was unpleasant. I would have liked to hire more nursing and medical staff, among other things to be able to offer consultations on Saturdays, but unfortunately this was not approved.

They weren't open all day back then either, but sometimes only half days. Tuesdays were completely closed.

Yes, Tuesday was always the day for our internal conferences, for discussing research projects and, of course, the annual institute excursion (smiles). Today, of course, you have a lot more staff, so it's possible to work all day. When I started at the Institute of Social and Preventive Medicine, we had a total of 14 employees.

That's right, today around 150 people work for the clinic alone, so a lot has happened. But the ZRM is your baby. When you look at it today, what goes through your mind?

Beautiful. I really enjoy what has come out of the last renovation. I find it inspiring every time I come in. Just reading the room names: ABCD - Accra, Baku, Capri, Dubai, that's the scent of the wide world. I think they've done an excellent job here and I only hear good things.

We are naturally delighted. Thank you very much for this excellent feedback and the interesting conversation.

Interview: Cécile Rasi

^[1] Robert Steffen: Emeritus Professor of Travel Medicine at the University of Zurich

^[2] Meinrad Schär: first social and preventive physician in Switzerland

^[3] CDC: Centers for Disease Control and Prevention, Agency of the US Department of Health and Human Services

^[4] Hans Otto Lobel: Dutch malariologist

^[5] Herbert L. DuPont: US-American infectiologist

^[6] WHO: World Health Organization

^[7] Phyllis Kozarsky: Professor of Medicine in the Division of Infectious Diseases at Emory University School of Medicine

^[8] International Society of Travel Medicine (ISTM): ISTM now has more than 4,000 members in 96 countries and is the largest organization of professionals dedicated to advancing the field of travel medicine.

^[9] David Bradley: Ross Professor of Tropical Hygiene Emeritus, London School of Hygiene and Tropical Medicine

^[10] Low and middle-income countries

^[11] Oswald Oelz: internist and high-altitude physician, head physician at Triemli City Hospital from 1991 to 2006

^[12] «Es kam gut, abgesehen von den Hirnschäden und den verlorenen Zehen»: Oswald Oelz, der Höhenarzt von Reinhold Messner, über sein Leben in den Bergen, NZZ. (01.11.2023)

^[13] Felix Gutzwiller: Swiss social and preventive physician and politician