BERLIN- Christian Drosten, a virologist at the University of Bonn in Germany, is among those leading the effort to understand the Middle East respiratory syndrome (MERS) and contain the disease. It is also one of the very few Western scientists who worked in Saudi Arabia, in collaboration with local researchers.
Friday, Drosten returned to Germany after a week in Saudi Arabia, where he studied what is behind the sudden explosion in reported MERS. Science Insider caught up with him during a stopover in Berlin
Q :. There were nearly 400 MERS cases and over 100 deaths in Saudi Arabia in the past two years. What is the situation like at the time
C.D:. There is a huge public awareness of the disease. Many people wear masks now. In fact, more than when I left when I arrived. In this 1 week, there was a net increase. People know that there is this virus and are cautious, and I think that will really help reduce the number of new infections
Q :. It certainly does not feel that way. Saudi Arabia has reported more infections in April that the world during the previous two years. The United States announced its first case on Friday, and before that there were cases imported in Greece and Malaysia. Is the disease out of control
C.D:. There has been much discussion about whether the virus has mutated to pass easily from human to human. But we sequenced three genomes of samples taken at the beginning of April to Jeddah, where most cases have occurred, two others later in the epidemic of Jeddah, and another of a patient to Mecca. They all look quite normal
Q :. But can you really tell from the genome if the virus has adapted to humans
[1945001?] CD It is almost impossible to tell from the sequence that there was a functional change in the virus. But we know that some parts of the genome are particularly important, and one of those is the binding domain of the receptor protein spikeQ :. The part of the virus that binds to human cells.
CD Exactly. And we see no changes. The remainder of the genome of the virus is also very closely related to previously sequenced genomes MERS. You really have to look quite hard to change at all, and when you find changes, there are other MERS genomes that have had these changes, too. It is not as the influenza viruses, which have a higher mutation rate way. Coronaviruses have enzymes correction so in general they are more stable genetically
Q: .. Yet the number of infections is rising
CD You can not compare the new numbers to those of the last few months. Until March 26, 459 tests were done throughout Saudi Arabia this year. Then, in just one month, just in the city of Jeddah, the 4629 PCR tests were performed. Something has changed dramatically, and that is the case definition.
Before the tests were done on patients who had pneumonia and needed [intensive care]. But now, people are tested not because they are sick, but because they have been in contact with a patient. Some of them tested positive, but many of them are not really sick
Q:.? Could the wrong test results
CD No, when I was in Jeddah I really tested the central laboratory where all PCR for MERS is done. I made them run nearly 0 RFP with water, interspersed with some real samples. The tests were carried out on all the machines they use, with two different PCR assays and by two different technicians. To my surprise, there were no false positives at all
We also rebroadcast samples of six health care workers who had taken care of a patient in Tabuk. they seemed to be positive for a low level. I can say unequivocally, these results are real. When you look PCR data on all recent tests, they are often very weak signals. These people probably just a very low concentration of virus in the throat. It is difficult to interpret. It is possible that they are infections which are rapidly controlled by the immune system. This can happen frequently in workers health care face many really sick patients
Q :. You say these people should not have been tested at all
[ CD: When the epidemic [03] SARS [severe acute respiratory syndrome], there was a definition strictly case. People who had contact with SARS patients, but no symptoms has not been tested with PCR. Instead, they were tested for antibodies later to see if an infection happened. This should happen now in Saudi Arabia, too. Asymptomatic individuals should not be tested with PCR. Currently, there are no available antibody test in the country. But you can list all these contacts and take a blood sample from each 14 to 21 days later and tested it outside the country. Three people in my lab are in Riyadh to establish an ELISA for antibodies
Q:.? But is not it good to know all cases, even if they are mild
CD: The question of whether there is a benign acute infection some people is scientifically interesting. But in cities like Jeddah, it brings the health system close to collapse. That's the big problem. So many samples are tested as laboratory capacity will not be enough for the actual event. And as more and more samples are tested, errors are inevitable. On top of that, if you identify all these mild cases and put them in isolation beds, then you have no beds left for the real case
. Q: What should be done with mild cases, then?
CD: This is a good option and is isolation at home. You can have people to call agency for public health every day to ensure that people stay at home. You can give them written information on what they are allowed to do, and what not. There are numerous examples for this. It has been used very successfully in Singapore during the SARS epidemic
Q :. Obviously, there are also very serious cases. At least 38 people died of MERS in Saudi Arabia in April.
C.D. I've seen the results of patients with huge concentrations of virus. These patients are highly contagious. Now, in some emergency rooms in some Saudi hospitals, patients are kept for a very long time, because there are no beds available in the rooms. If there are such highly infectious patients among them, it is clear that you get nosocomial infections and which is the other thing we see at present. You must remember that the absolute number of cases is still small. Few hundreds. So, just a hospital home may increase significantly and give the impression that the whole of the epidemic is changing
Q:.? You also looked at how easily the virus is transmitted at home
CD We will present a paper on this soon. We examined 26 index cases and 280 people they had close contact with. These are almost all family members in some cases also maids or drivers. We looked very closely with PCR and antibody tests, and at the end you can say nine of the 280 contacts were infected. And these are people who really huge exposure. This means that the virus reproduction rate is 0.3, not close to 1, as others have argued
Q:.? So the only real chance MERS moments to spread is in hospital
CD I think those hospitals where there are problems hygiene fueling this small outbreak
Q :. What about the political situation? Deputy Health Minister Ziad Memish, you work, received a little criticism.
C.D :. Some people have accused that he holds important information to secure high ranking publications and things like that. But this is false. I work with him since October and I had a good impression of him from the beginning. It is an epidemiologist Western-educated who knows what he's talking
Q: .. Others have accused it requires to be the first or last author of a publication just return to provide samples
CD Get really good samples under controlled conditions is not easy in a country like Saudi Arabia. I think Memish organizes there is a huge contribution that deserves a first or last author. It does not have a problem. Memish really motivates people, he is very busy and built an incredible network over the past two years. It is a great loss that weakened his political position
Q:.? You mean the new Health Minister Adel Fakieh is marginalize
CD He formed a new advisory committee and Memish not part of it. This is a big problem, I think. This means they are starting from scratch. All the knowledge and the network Memish established is not used. My impression was that the committee is dominated by clinicians and clinical microbiologists. They know how to treat patients of course, but not necessarily how to deal with an epidemic. I think Memish really developed a kind of gut feeling MERS for the past two years and is not used more. I think this is the biggest mistake being made in Saudi Arabia at the time
Q :. The ministry also announced that three hospitals in Jeddah, Riyadh and Dammam will be devoted to treating patients MERS. Is it a good idea
C.D:. Of course, it is a good idea to build these facilities so that patients can be treated better. But what is most needed at this time is a massive campaign to hospital hygiene. Sending teams in hospitals to retrain health workers, who come from all over the world. Teach them the proper infection control. That would change a lot
Q: .. Even when this is done, there have been many studies suggesting that camels are a major source of infections as well
CD camels remain a source. Interestingly also, when we talk about Jeddah: Most camels are imported to the Arabian Peninsula come through the port of Jeddah. So you might think to test all young camels arrive and quarantine at the port until the virus is gone. But it would be a huge logistical challenge. Who would do the testing? When the camels must be locked all this time? A vaccine is more realistic and there are some good candidates
Q: .. But none of those tested in camels still
CD: is really difficult to get a sufficient number of animals that have not already had an infection. Where are you going to get? You can not just buy a circus. And you would have them are not adult animals, because they are really big and barely fit in all research laboratories. It is a real challenge.
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