Professor Mantovani, the decisions of various countries to change the criteria for administering the AstraZeneca vaccine have confused many people.
«I understand the hesitation in the face of contradictory messages, which generate uncertainty. All the available data on possible adverse events in young women should be analyzed to protect public health. According to a recent publication, the serious cases of thrombosis observed in relation to the vaccine could possibly be caused by the formation of autoantibodies, as happens, in very rare cases, during treatments with heparin: a condition called Vipt (Vaccine induced prothrombotic immune thrombocytopenia). If confirmed, observation could guide the diagnosis and therapy of these, albeit very rare, adverse events. For now, the analysis conducted by Ema on the Oxford AstraZeneca vaccine has reassured that it does not cause an increase in the frequency of thromboembolism, we await further analysis. In Great Britain there was no excess of thromboembolic events in the 20 million people vaccinated with Oxford AstraZeneca compared to those vaccinated with BioNTech Pfizer and compared to what is normally expected. In Humanitas we have vaccinated over 22,000 people without unexpected problems. We await more data, but three young women in my family have been vaccinated with Oxford AstraZeneca and I am calm ».
In general, does anyone who has had Covid-19 have to get vaccinated?
“We know that the disease gives a certain degree of protection, estimated at 80% over an observation period of 5 to 7 months. Very recent data on 12 thousand subjects who are part of the British health personnel and on 4 million people in Denmark have confirmed that those who have had Covid, confirmed with molecular tests, have an important degree of protection, but only in the order of 40 % in those over 65 years of age. So those who have had Covid must get vaccinated, but several studies show that a single dose is enough, which, among other things, would save two million doses of vaccine in Italy, while on a global scale this strategy would “save” one hundred million of vaccines at no cost. Worrying about this is in our best interest. This is the strategy of the two: solidarity for ethical reasons and our own safety, because if we do not get the vaccines to low-income countries, we will be overwhelmed by the variants. In this regard it is important, albeit somewhat overlooked, that the Prime Minister recently mentioned in the Senate as a global health activity that we must support Covax (Covid-19 Vaccine Global Access), the international program to provide poor countries access to anti-Covid vaccines ».
Is the second dose of vaccine necessary for everyone?
“In the largest population studied, in Israel, after the first dose of Pfizer the data indicated a protection of 60% against severe disease and 90% after the second dose given at the right time, then the second dose, in general. , serves. The Oxford AstraZeneca vaccine was born as a single dose then it was decided to do the second one too, delayed up to 12 weeks, when it was realized that there was a problem with the duration of the immune response. As for the Johnson & Johnson vaccine, also based on adenovirus, the data indicate a protection of 77% after a single dose, lower in South America and Africa, where it is around 50%. As for Sputnik V, also on an adenovirus basis, the rates are apparently even better but the data for now refer to 27 days after the first dose ».
Is vaccine protection effective in fragile individuals?
“The data indicate that in some categories of fragile subjects the vaccine may work a little less well: we must certainly vaccinate fragile people, but also study how to protect them as much as possible, then understand when to vaccinate them, identify which of them have a greater or lesser response. We must accompany vaccination with research programs that make it possible to better respond to their needs. In this sense, collaborative studies are underway between various institutes that will probably have the support of the Ministry of Health ”.
Some think that if we continue to vaccinate we will select more variants.
«The more the virus replicates, the more variants it generates. We need to stop the virus rush. We must prevent it from circulating, here and elsewhere ».
Is the reduction in infections in the UK more due to widespread vaccination or more to closures?
“I believe they both contributed. As for vaccines, we have seen it too: in the first population we vaccinated, that is health workers, there was a collapse in infections. And the lockdown is needed for the reason just mentioned: to prevent the virus from circulating. One of the large population studies, conducted in Scotland, shows that both are needed. The important thing is to conduct serious studies in order to have solid answers, and this also applies to drug therapies ».
Speaking of drugs, where are we? And what prospects are there?
“Unfortunately, there have been several failures: for example old antivirals, ivermectin, colchicine, the azithromycin-hydroxychloroquine combination did not stand up to the tests of rigorous trials although they had given hope in observational studies limited to a few tens or hundreds of subjects. In reality it is not strange because these studies can have value if they generate hypotheses, but the hypotheses must then be verified in rigorous prospective studies, otherwise we risk giving toxicity to patients. Caution is needed, even more so if these trials are not published by accredited scientific journals. Another paradigmatic case was those of the hyperimmune serum on which the American National Health Institute suspended the experimentation in outpatients due to lack of efficacy ».
Does cortisone work?
“Dexamethasone, and by extension cortisone drugs, has been shown to be active in patients with respiratory failure and in need of respiratory assistance, while in other conditions the data suggest that it may even be harmful. This is clearly stated by the IDSA (Infectious Disease Society of America) guidelines, which are very strict and represent a point of reference. Even Anthony Fauci, moreover, on Jama (the magazine of the American Doctors Association), expressed concern because we see, and we see them in Italy too, arriving patients in the emergency room treated with dexamethasone outside the indications. The reason is that it is a drug that inhibits inflammation but also the immune response, which, in most cases, in otherwise healthy people, usually manages to fight the infection. Treatment with dexamethasone in the early home phase in the absence of severe respiratory insufficiency is not foreseen in any guideline that I know of, and the Emilia-Romagna Region has warned the use of it in the early home phases. A lesson that can be learned from the dexamethasone case is the importance of a public and universal health service also as a large research laboratory, since we have a lot of information, positive or negative, from the Recovery Trial which is a study carried out in the context of the service. English health care ».
What about vitamin D?
Vitamin D failed in the verification study, even though there was a rationale for conducting it, as an association was observed between low vitamin D levels and a poor course of infection. And we know both that vitamin D is often deficient in the elderly and that it is important for the immune system. However, those who need vitamin D in general must continue to take it ».
Covid, vaccines and treatments: the insights
No hope then on the drug front?
“On the contrary, for example, there are interesting data for strategies that aim to inhibit molecules such as interleukins 6 and 8 and the Jak enzyme that play an important role in the serious inflammatory phenomena that occur during Covid. We await the results of rigorous testing in this regard. For monoclonal antibodies the situation is in the making, but combinations of monoclonals are already more than promise. The dream we all have is to have a pill like those for the HIV virus, which can keep the infection under control, and there are compounds in phase 2 of experimentation that give us reasons for hope in this regard. If things go well, by the end of the year perhaps we will be able to have an armamentarium of tools studied in serious protocols from which to choose according to both the patient and the stage of the infection ».
Could we learn more from genetic studies?
«The disease is a cross between genetic predisposition and autoimmunity. Many have tried their hand at genetic risk analysis. Recently all those who have conducted studies on genetic polymorphisms and the risk of Covid-19 have come together in a global effort and their work has resulted in a scientific document submitted for verification to be published in a very authoritative journal and in the meantime is already available in open access (accessible to all for free). What is striking is that there are 2,800 authors. An unprecedented proof of collaboration ».
April 6, 2021 (change April 6, 2021 | 11:24 am)