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PhD in Biological Sciences from the University of Valencia since 1995, Santiago F. Elena knows viruses up close. His research focuses on the study of the mechanisms that generate and maintain the enormous genetic diversity of microorganisms and, particularly, RNA viruses. He is currently a research professor at the Institute for Plant Molecular and Cell Biology, joint center of the UPV and CSIC, where he leads the research group for virology and evolutionary systems. He welcomes us to his office in the lab to tell us about viral diseases, but a particularly lethal one captures the conversation: the Ebola virus. «Because it interferes with the antiviral response of our cells, there is a period during which all our defences are not enough to control the virus, which will continue replicating and colonising. Moreover, the virus is not adapted to humans, so it causes a generalised infection. It infects any cell that is susceptible to the virus. Then kills it. This virus infects many different tissues and keeps on destroying them.» Nevertheless, Santiago F. Elena hopes there will soon be an effective vaccine against Ebola.
What is a virus?
The simplest structure of a virus is a nucleic acid molecule coated in protein. Unlike bacteria, for example, which are cells. Being a cell means being autonomous, able to replicate for itself. A virus, however, needs to be a parasite, it needs to enter a cell to replicate. But not all viruses are bad, there are absolutely asymptomatic viruses. If a virus is in a cell but is able to replicate without altering the metabolism of the cell, there will be no disease.
What factors favour the emergence of new viral diseases?
Possibly it is related to genetic alteration. If we are cultivating land that was once virgin forest, and we are forcing cultivated and wild plants to be in contact, or if we have livestock in places where there was nothing before, and now they are in contact with wild animals, there may be the possibility that an insect bites an organism and transmits something to another. In the case of human disease the process is basically the same. We are entering at a massive scale in places where no humans existed before, or there were very few. Ebola has existed for years, but if someone ate an infected animal he and his closest people died, and that was the end of it. It is much easier to move now and this favours the emergence of more diseases, and makes it easier for them to spread.
Why is it so difficult to control some infections, or to find vaccines for diseases caused by viruses like Ebola or HIV?
It is a complex issue. Basically, I would say, as the virus is within the cell, it is protected. We need to develop an antiviral that is capable of blocking the replication of the virus within the cell without affecting it. And that’s the problem: how do you interfere without harming the cell? Therefore, the most effective so far is vaccination: injecting pieces of deactivated virus or live attenuated virus. Control, therefore, involves prevention rather than treatment. AIDS is different to other viral diseases because it is a retrovirus, integrated in the genome of host cells, hidden. So far the different drug combinations are used as a therapy. As for Ebola, the virus interferes with the immune response against infection and the natural immunity of the cell is blocked. The virus can then replicate without interference. Why don’t we have a vaccine? Well, I’m not sure. Maybe the investment was not enough, because we did not care about Ebola until now. Or maybe because the tests that have been made are limited and not checked all that well. But I’m sure soon one of them will work well and will be used as a vaccine.
The Ebola virus was identified around forty years ago. However, it is now that is experiencing the most virulent outbreak. Why?
Mobility is one cause, no doubt. There have been a number of outbreaks in the past, but they were very limited geographically, occurring always in very isolated regions. A few people were infected and with their death the outbreak was extinguished. A good thing, in quotation marks, Ebola had before is that, being so aggressive, once symptoms have appeared the person can not move. Therefore, the probability that this person with symptoms will transmit the disease to others is very small compared to other viruses such as the flu. The problem comes when the virus reaches a large, highly populated city. It is very easy, even if you are very sick, that someone will be in contact and get infected. Another reason would be the lack of hygiene and sanitation infrastructure. But the main problem is when the virus comes to a big city, with an international airport.
So from now on the epidemic could spread through Europe?
We could see more cases. A different question is whether an epidemic could start. If the European health-care system becomes aware and every person showing symptoms is managed as a possible risk, the probability of new infections will decrease. But we will see more cases of infection, sure. Of course, the danger lies not with immigrants jumping the fence in Melilla or coming by boat. Those people have been walking around the world for months and months. The problem is carrying the virus by plane, and we have imported it here with full honours.
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«It is much easier to move now and this favours the emergence of more diseases, and makes it easier for them to spread»
«The danger lies not with immigrants jumping the fence in Melilla or coming by boat. The problem is carrying the virus by plane, and we have imported it here with full honours»
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You seem critical with the procedures followed by the Spanish Government. Is that so?
I can understand all the disquisitions on morality and the need not to abandon «our own people». The problem is always the double standards of this government. There have been many cases of sick Spaniards abroad, and they received no attention. They decided to bring the missionaries, I think pressured by the Church, or because of a moral, political or personal issue… But the risk it entailed was not properly assessed. The first thing that they should take into account is whether the facilities and experience in Spain were adequate for a problem like this one. And the answer is no. The job is botched, as we see, over and over again. The protective suits are not appropriate, nor is their disinfection, or the compartments to take it off… An alternative would have been to treat the missionaries in the place of origin of the disease, that is, bring the military to put together a proper field hospital and treat them there with all the guarantees.
To sacrifice or not to sacrifice Excalibur. Did the infected nurse Teresa Romero’s dog pose a threat or an opportunity?
As a scientist I would say that Excalibur was a good opportunity to study how the virus operates in dogs. Now, the question is: do we have the facilities necessary to have an Ebola infected dog? There are two animal safety laboratories in Spain, CReSA in Barcelona and CISA in Madrid, and both have level 4 bio-safety labs, which is already more than we have in the hospital. They could have taken the dog there. I do not know who made the decision to kill him, but surely it was again a political decision by a panic-overwhelmed person who wants to get rid of problems fast. But I wouldn’t have killed it, I would have studied it.
Are the media are being sensationalist?
Absolutely. People panicking is due to the lack of information. People need to be informed seriously, but the media chooses scaremongering. We need to get information, but without the drama, because that increases the fear. Right now there is another epidemic in Spain, Legionella, which has killed a dozen people. If what you evaluate it in terms of victims, Legionella is more important here. But it is not interesting, it is not commented upon.
Laying on of hands, sea water, essential oils of cinnamon and oregano, silver ions or rectal ozone therapy. These are some of the alleged cures for the Ebola virus being advertised already. How does one react to these claims?
The Ministry of Health should prevent the visibility of any pseudo-medicine and pseudo-science. From one day to the next one, a lot of Ebola remedies have been invented. Who did they try them on? How often do they work? It’s all a hoax that exploits the fear and ignorance of people. Given this, the Ministry should take a belligerent position. But considering that it was the Virgin of El Rocío who got us out of the crisis…
Are we nearing total eradication of viral diseases or is there a long way to go?
Much is being investigated in human, animal and plant viruses. We are developing new drugs to treat the symptoms and try to mitigate the effects of infection. There are also many lines of research to control viral diseases, trying to understand the molecular mechanisms of viruses. Once known, we have the opportunity to develop molecules that specifically target each of the processes. In addition, completely alternative therapies based on interfering RNA molecules to make the cell degrade the virus before it acts are also being explored. But we are not close to the eradication of viral diseases. We will develop an antiviral, a resistant strain of the virus will appear and we have to develop a new antiviral, surely a modification of the first one. It is a constant chase. Perhaps the solution is having effective vaccination campaigns, as happened with smallpox, which kept the virus from being transmitted. But ultimately, the absolute eradication of viral diseases is impossible.
Íngrid Lafita. Journalist. Mètode, University of Valencia.
© Mètode 2014.
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«Right now there is another epidemic in Spain, Legionella, which has killed a dozen people. But it is not interesting, it is not commented upon»
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Íngrid Lafita
