It is the conclusion of a study on the data of over 37 thousand patients around the world. But the dynamics are not yet clear and no causal links have been identified
The countryside vaccine versus Covid-19 accelerates its run, yet some countries of the world may not be securing adequate coverage before early 2023. Prior to that time, i flu vaccines could help ward off more serious outcomes of the disease from Sars-Cov-2, including i admissions to intensive care, the episodes of deep vein thrombosis, of sepsis e stroke. This is what emerges from a large retrospective study by the University of Miami Miller School of Medicine, presented at the European Congress of Clinical Microbiology and Infectious Diseases (Eccmid), but not yet published, which would suggest a certain protective effect of flu vaccine, even without identifying causal links. At the base of these results there would be a non-specific and generalized activation of the immune system following vaccination.
The results of the study
If already some studies of medium size had shown good flu vaccines resource in addressing the Covid-19 pandemic, the analysis conducted by researchers at the University of Miami, led by Susan Taghioff, offers for the first time data on tens of thousands of patients (37.377) who have been infected with Sars-Cov-2, collected in countries around the world (including the United States, United Kingdom, Germany, Italy, Israel and Singapore) thanks to anonymous electronic medical records stored in the search database TriNetX.
To study the effects of influenza vaccineand, the researchers divided the patients into two distinct groups: the members of the first group had received the anti-flu vaccine between two weeks and six months before the diagnosis of Covid-19, the others had not received any vaccines before contracting the virus. They have been evaluated 15 different outcomes adverse disease, from emergency room visits to pneumonia, to even more serious ones, such as sepsis, stroke, thrombosis deep vein and death.
The results confirm what has already been hypothesized by previous studies: those who had not had the flu vaccine had one significantly higher probability (up to 20% more) to be admitted to intensive care. In addition, they were also significantly more likely to go to the emergency room (up to 58% more), develop sepsis (up to 45% more), have a stroke (up to 58% more, and develop thrombosis. deep veins (up to 40% more). However, mortality remained unchanged between the two groups.
Boosting the innate immune system
The data, therefore, would suggest one certain protection against Covid-19, or rather the risk reduction to develop some of the more severe outcomes of the disease. It should be noted that no causal relationship was found between these results and the flu vaccination and it is not clear how this can offer protection against the coronavirus.
Most theories would explain these numbers following the strengthening, by the flu vaccine, not only of the immune system adaptive (i.e. the one that specifically recognizes the pathogens with which it comes into contact), but also of the innate, the body’s general defense system, which intervenes in the early stages of an infection because it is non-specific. If these protective abilities are confirmed, the flu vaccine could be used to buffer the emergency in those countries in which the vaccine for Covid-19 is in short supply.
Why influenza vaccination is important
The authors add that they are more research needed and prospective studies to demonstrate and understand this possible mechanism. Be that as it may, they are always there very good reasons to carry out the flu vaccine. All health care institutions, in fact, including the Ministry of Health and the European Center for Disease Control and Prevention (Ecdc), agree in emphasize the importance of vaccinating against the flu the categories at risk and those most exposed, especially in such a delicate moment for global health.
As stated on the website of the Center of disease control and prevention US, flu vaccines they cannot prevent Covid-19, but surely they will reduce the burden on the health system, hospitalizations and deaths due to flu diseases, and will conserve the scarce medical resources for the care of people infected with coronavirus. “Continued promotion of the flu vaccine also has the potential to help the global population avoid a possible simultaneous flu and coronavirus epidemic – glosses Taghioff -. Regardless of the degree of protection offered by the flu vaccine against the adverse outcomes associated with Covid-19, the simple ability to conserve global health resources keeping the number of influenza cases under control is reason enough to support continued efforts to promote influenza vaccination.