Germany has gradually begun lifting the confinement since 27 April. What will happen from there?

At the moment, we are seeing that the intensive care units in Germany are full up to half. This is because we started large-scale diagnostic tests and the epidemic stopped, that is, we managed to have the infection rate for each patient (reproduction rate) lower than 1.

In the current context, I call it the "paradox of prevention." There are people who argue that our reaction was disproportionate and there is political and economic pressure to return to normal. The plan of the federal government is to gradually lift the lockdown, little by little, but since each Lander can decide and can enforce its laws, I fear that in implementing that plan we will see great creativity and imagination. I fear that the reproduction rate will increase and we will know a second wave of contagion.

If the containment was prolonged, could the disease be eradicated?

In Germany, there is a group of specialists studying the future behaviour patterns of this disease, which proposes that by extending the confinement a few more weeks, the circulation of the virus would be greatly destroyed and a reproduction rate of less than 0.2 would be achieved. I usually support your approach, but I have not yet taken a decision. In fact, the reproduction rate is only a measure, an approximation. It does not indicate where the most vulnerable groups, such as nursing homes, are, and in these groups it may take longer to end the disease and the infection re-escalate at high speed, even in a confinement state.

If there is another manifestation of the disease, could it be delimited?

Yes, but this cannot be done if we only take into account contact between human beings. We already have evidence that nearly half of the infections occur before the person who transmits the contamination develops symptoms and that people remain infected for at least two days before symptoms develop. This means that the experts who make contacts are in a race against time. They need help to know as soon as possible which are all potentially contaminated people, which will require the use of electronic contact tracing methods.

Are we close to achieving herd immunity?

In order to achieve collective immunity, it is necessary that 60 or 70% of society has antibodies to the virus. Antibody tests have shown that in Europe and the United States we are below 10%, but these tests are not entirely reliable. Everyone has problems and false positives. Collective immunity is not the total solution. It's based on citizenship being confused, but taking into account the networks that people create to relate, we have reason to think that not all society can be infected at once. These contact networks are constantly changing and then other people are put in front of the virus. In this way, waves of infection can occur. Another factor that can influence herd immunity is whether other coronaviruses, such as the common cold, offer protection for this. We don't know, it's an option.

Should all countries be testing all citizens?

I'm not sure. In Germany, with the great testing capacity we have and most tests have targeted people with symptoms, the positivity rate does not exceed 8%. I think it is better to test specific parts of society, to which they are really vulnerable. Hospital workers and nursing homes, for example. That is not being done in Germany, but we are moving in that direction.

Another goal to consider in the tests is that first-week patients with symptoms, especially older ones, come to the hospital too late, already with bluish lips and instead of intubation. We need an inspection system that, looking from the watchtower, takes samples regularly among the population, and that is attentive to the rate of reproduction of the virus.

What do we know about seasonality of the virus?

Not too much. The modelling team led by Marc Lipsitch, from Hardvar, has indicated that transmission of the virus could slow down in summer, but that the effect will be very low. I don't have better data.

Can we say scientifically that the pandemic originated in China?

He thinks so. On the other hand, I cannot sign that he left at the Wuhan food fair. You're more likely to start where another animal grows. In an intermediate host.

What do we know about that middle host, he's "poor pangolin"?

Nothing leads me to think that the virus passed to humans through the pangoline. Interesting information exists in the literature on SARS disease.

The virus appeared in the Cibelets, but also in the Raccoons, and the press did not echo it. Raccoons are at the core of the Chinese industry. They breed them on farms and hunt them in nature. For her skin. If someone gave me a few hundred million dollars and access to China to find the cradle of the virus, I'd like to look at the raccoon nurseries.

Will it be useful to find the first human being infected by this virus, sick zero?

No, the patient would probably have been infected with a very similar virus, so it wouldn't help us solve the problem we have now. I don't think it can be argued that it would help us prevent future pandemics, because once we've seen this coronavirus, humanity will be immune to the next coronavirus associated with SARS. There will be other coronaviruses threatened, one of the great candidates is Middle East Respiratory Syndrome, but to understand that risk you have to see how this virus progresses in the Middle East ganglia.

Is human activity responsible for the virus passing from animals to humans?

The coronaviruses, as soon as they have the opportunity, try to change the organism they are based on. The use we make of animals is contrary to the principles of nature and we ourselves create the possibility of viruses moving from animals to humans. Farm animals are in contact with other wild animals. Accumulation in large groups increases the chances of infection of the virus among them. Man comes into contact with these animals, for example, by eating meat. This may be one of the coronavirus emergence routes. In the Middle East, ganglia are farm animals, and in them they have MERS disease and coronavirus 229 E, which is one of the causes of the common cold. Our livestock is the original host of coronavirus OC43, for example.

Common influenza has always been considered to be the highest risk of the pandemic. Is that still the case?

No doubt, but we cannot rule out another coronavirus pandemic. When Ebola first exploded in 1976, many thought it wouldn't happen again. But he came back before he was 20 years old.

Is all the science that's been developed about this coronavirus correct?

No! At first, in February, there were a lot of interesting sketches. Now you have to look at 50 to find a well-grounded and interesting report. Many of the research resources are being misused.

German Chancellor Angela Merkel has taken the flowers for her leadership in this crisis. What does a good leader do?

He is well informed. It helps him to be a scientist by training and to know how to manage numbers. But I think fundamentally it's their way of being, which has the ability to make solid base decisions and transmit security. Perhaps one of the hallmarks of the leaders is to use the situation for political gain. They know that this may be contradictory.

Is there anyone who keeps you from sleeping?

In Germany, people see that hospitals are not crowded and do not understand why shops have to be closed. They only look at what happens there and not at what, for example, happens in New York or in Spain. That is the "paradox of prevention." For many Germans, I am a devil who is sinking into the economy. I get death threats and pass them on to the police. But other emails cause me more discomfort: those who tell me they have children and care about the future. They're the ones that keep me from sleeping at night.