[ad_1]
Coronavirus – All the news: Everyone is waiting for the vaccines for the new coronavirus SARS-CoV-2, to have a substantial response to the Covid-19 pandemic.
Scientists certainly recognize the critical importance of vaccinesBut be sure to note that there are uncertainties about vaccines, some of which will remain after the first one appears. That is why they emphasize the need for clarity and honesty about what we will know about new vaccines and what we will not, even if this partly fuels some people’s excessive suspicions.
As Peter Doshi reports, Deputy Editor of the British Medical Journal (BMJ) and Assistant Professor at the University of Maryland School of Pharmacy, in a BMJ article, said vaccine trials weren’t designed to tell us whether vaccines could actually save lives. No vaccine test is designed to detect whether the vaccine will reduce admissions to hospitals and intensive care units (ICUs) or deaths from coronavirus.
According to the APE-MPE, several tests are in their third and final phase, but even if one of them is declared “effective”This does not mean that it will be shown to prevent people from becoming seriously ill or dying from Covid-19. It will not even prove, as Dr. Doshi points out, that the vaccine will effectively prevent transmission of the coronavirus from the person who has been vaccinated.
As he explains, all phase 3 clinical trials evaluate mild, not severe, symptoms of the disease. “The clinical trial is underpowered to assess whether the vaccine can actually reduce hospital admissions,” Tal Jacks, the medical director of Moderna, who is testing one of the vaccines, told BMJ. This, according to Dosi, is in part due to the fact that most people only have mild symptoms of Covid-19 and therefore in vaccine trials, e.g. relatively few serious cases will occur in 30,000 people.
“Covid-19 hospitalizations and deaths,” he adds, “are simply very unusual in the study population for an effective vaccine, to show statistically significant differences in a trial of just 30,000 people.” The same can be said about whether a vaccine can save lives or prevent the spread of the virus. The tests are not designed for such a thing ”, something that Zax de Moderna confirmed in BMJ.
Otherwise, the population sample size and the duration of the vaccine trial should be much longer, which is unacceptable due to the urgency of the situation. The Moderna test is designed to simply determine whether the vaccine can prevent Covid-19 disease in a human.
As in the corresponding Pfizer and Johnson & Johnson vaccine trials, the goal is to find a 30% reduction in the incidence of laboratory-diagnosed Covid-19 in the vaccinated group relative to the control group. The pharmaceutical industry and many scientists believe that, as with the flu vaccine, the coronavirus vaccine will protect even better against severe Covid-19 than against mild illness, something that will be seen in practice after a while. .
Question marks for the elderly
On the other hand, according to Dosy, few, if any, vaccine trials have been designed to determine whether older people in particular will benefit from the vaccine, although they are at especially higher risk than Covid-19. This is because there are not enough older people in the vaccine trial to show that a vaccine actually reduces the incidence in older people. There is a similar uncertainty for other groups (children, immunosuppressed, pregnant women) who are also underrepresented in vaccine trials. Dosi, however, estimates that there is still time to improve the design of the tests.
In another Science article, Mark Lipsic (Professor of Epidemiology, Harvard University School of Public Health) and Natalie Dean (Assistant Professor of Biostatistics, Epidemiology, University of Florida) point out that the possibility of an anti-Covid-19 vaccine that provides little or no protection to high-risk groups such as the elderly and those with other chronic diseases (comorbidities), but reducing the risk of infection or transmissibility of the coronavirus to young adults. In this case, there will be indirect protection for the elderly, but only if a large percentage of the very young are vaccinated.
Furthermore, they emphasize that even after the approval of some vaccines, questions will remain such as to what extent vaccines can prevent infection or reduce person-to-person transmission. Therefore, further post-marketing vaccine trials will be needed to assess the efficacy of more than one vaccine (ideally, by individual population group).
In an article in Nature, Dr. Kanda Subarao, director of the World Health Organization Influenza Research Center in Australia, who advises each year on the composition of the influenza vaccine to make it more effective, points out that “we have many uncertainties regarding vaccines against Covid-19.”
Among other things, even when vaccines that have been shown to be safe and effective are approved, It remains to be seen if one vaccine is more effective than another (each vaccine will be approved after being compared to a placebo-type vaccine and not to other vaccines), how effective the vaccines will be in vulnerable groups (who are underrepresented in clinical trials phase 3). ), if the vaccines will prevent the transmission of the coronavirus (therefore, if the vaccinated can go back to work without further precautions), if they will avoid the severe and life-threatening Covid-19, how long the immunity will last after vaccination. to.
The authorities of each country will be asked to decide which of the approved vaccines they will use, in which part of the population, with what priority and with what frequency the vaccinations will be. He also emphasized that it should be understood that even an effective vaccine will not prevent infection of all vaccinated people, nor will it certainly prevent vaccinated people from infecting others. “The best the authorities can do,” he says, “is to be very clear about what is known and what is unknown, engage the public in the dialogue by taking their views seriously, and build trust through transparency.” .
Two out of three need to be vaccinated
As stated, it is essential to have a broad willingness to be vaccinated, Since achieving herd immunity will require the participation of more than 60% of the population or even more than 70%, that is, at least two out of three. At the same time, it should be clarified that the existence of vaccines should not disable other measures, such as the use of a mask, hand washing and distance.
Finally, a recent study by the US analytics firm Rand concluded that if a “vaccine nationalism” prevails and some large countries exclude others from “their” vaccine, then this could cost the world economy a GDP loss of up to 1.2 trillion dollars a year. This will happen if some countries not only give their own citizens top priority, but also “stockpile” vaccine stocks, leaving other countries without vaccines.
The study shows that as long as the coronavirus is not controlled globally, something that requires coordinated vaccination action, there will be economic costs for all countries, even those that have shown vaccination nationalism. Even if only poor countries are left without access to vaccines, the hit to the global economy will reach 153 billion dollars a year (40 billion for Europe). If there is no vaccine, which is unlikely, the global cost is estimated to increase to $ 3.4 billion a year.
See the latest news from Greece and the world, as it happens, on Newsbomb.gr.
Read also:
Coronavirus: terror over the explosive increase in deaths and imports: the worst ahead
