Long He is also one of the three CSIC researchers - along with Luis Enjuanes y mariano esteban- who are working on Spanish-made coronavirus vaccines. Their project consists of placing a gene for a SARS-CoV-2 antigen in a synthetic DNA vehicle (a plasmid) that can be introduced into the patient's body and induce protection against infection. There are two advantages of its vaccine candidate: it can be stored at room temperature and, as it is a synthetic DNA vaccine, it can be quickly remade to adapt it. to virus variants that are more resistant.
What assessment do you make of the announcement made by Moderna about work on a single vaccine against flu and Covid-19?
What it is about is preparing a double vaccine. On the one hand, the annual one they face against the flu virus and that of SARS-CoV-2 will be added to that. That is what I have understood reading the statements. But the ad itself suggests much more than it says. These people from Moderna are very smart and, precisely in a context where the pandemic could 'spread the flu', they have thought: 'Let's go ahead and say that we are going to do this.' Whoever talks about Moderna (in this case the pharmaceutical company's CEO, Stephane Bancel) does not speak so much for the scientists, but for the markets. They are strategies. They think about seeing how to get the stock to go up.
But does it make sense to work in that direction?
It does make sense, of course. It's sensible and it can be done. Of course. As an idea it is not crazy. Which can be useful, too. It can be done perfectly; From a theoretical and conceptual point of view, it is perfectly plausible and, indeed, a double vaccine that protects against influenza and SARS-CoV-2 would be an advantage. But, before 2023, it cannot be done. Because it has a series of drawbacks related to the temperature of each vaccine, which complicates distribution.
How would the distribution be complicated?
A seasonal flu vaccine is made every year using the latest strains from the previous year's infection. It is prepared so that, the following year, people who are in risk groups have less chance of catching the infection and that is maintained at four degrees. Moderna's SARS-CoV-2 vaccine requires freezing to at least minus twenty degrees. If you put the two vaccines together, unless the company has a way to do it that requires less freezing, all you do is complicate the distribution of the flu vaccine. It's a technical complication, nothing more than that.
In any case, is this the first time that there is talk of a joint vaccine for Covid and flu?
Yes. It's logical. Because it is the first time that, after the appearance of the omicron variant, it is being seen that the mutations are directed towards conversion into a seasonal respiratory infection, which theoretically had to happen. Another thing is that it will arrive quickly. So they (the pharmaceutical company Moderna) have taken advantage of it and said: 'Well, we are going to make a double.' Except, I insist, they have to solve the issue of conservation.
Does Moderna advance now that it is working on a unique vaccine have to do, then, with that Covid-19 'flu' scenario towards which we seem to be heading?
From the beginning, all of us experts thought that, if it behaved like other infections, that should happen and it seems that yes, it is indeed behaving as we all expected. The 'flu' is going to occur, but not within three months. With a little luck it will be next year. It does seem that this omicron variant is less aggressive in the lung and transmits much more quickly, but that does not mean that it is less serious. People continue to die in hospitals. Until it produces another mutation that is more dominant and actually milder, it will be months. We must keep in mind that we are having Omicron here and in other countries, but there are other places in the world where this variant is not present. When this wave ends we will not be experiencing 'flu', no joke, we will still have an infection that is transmitted much more quickly and that, as a percentage, sends fewer people to the hospital compared to those who become infected. But the percentage is one thing and the people who continue to enter the ICU and continue to die are another. It is normal that people have taken the 'flu' thing with great enthusiasm because they are tired.
What do you think about the administration of a fourth booster dose?
This new variant is less sensitive to the action of specific antibodies. Because it's different. Much more attention has been paid to antibodies than to the cellular memory response and that is becoming very important now. If a good and long-lasting cellular response is achieved, then people will not have to be vaccinated so many times. You have to think in the medium term. You cannot be vaccinating every three months with the same thing because the immune system becomes 'tired' and the response is lower. The third dose is still working very well. Produces a 23-fold increase in protection. But, the fourth dose, at least in the case of Israelis, is not giving such good results. You cannot think: 'I start vaccinating everyone every three months'; not only for strategic reasons, but scientific ones.
You are one of the three CSIC researchers who are developing projects to achieve a vaccine against covid-19. What phase is yours in?
We are finishing the preclinical phase. We know that we protect the "humanized" mice one hundred percent against a lethal dose of the virus.
