ROME To further relax the measures “it is necessary to keep the RT below 1, to approach the threshold of 50 cases per week per 100 thousand inhabitants (now it is 157), to further reduce the pressure on health services and to have half the population vaccinated”. Professor Silvio Brusaferro, president of the ISS and spokesperson for the CTS, draws the line beyond which we can regain another good slice of freedom. Despite the variations.
Professor, Rt, albeit slightly, has increased, reversing the trend. Do we still risk a tailwind of the epidemic?
«We are in a delicate transition phase, of slow but steady decline in the spread of the virus. To prevent the curve from growing again, it is necessary to intervene at three levels: first, to continue vaccinating at the rapid pace of the last few days; second, to monitor the situation well and intervene locally where necessary; third, but certainly not last, until we have a greater number of immunized people continue to adopt prudent behavior in order not to be forced to adopt restrictive measures ».
What would you say to those 14 million Italians who only received the first dose of the vaccine?
“To continue being cautious. First of all because it takes no less than two to three weeks before a first immune response forms, which is completed after the second dose. Masks and distancing will still be needed until a large part of the population is vaccinated, even those who are immunized cannot exclude the risk of infecting those who are not ».
With what values can we think of loosening the measures again, perhaps starting from the curfew?
«First of all, it is necessary to keep the RT below the safety threshold of 1. Then further reduce the pressure on the health services and get closer to that threshold of 50 cases per week per 100 thousand inhabitants, which allows us to resume a systematic tracking of cases. Until we have the majority of the population vaccinated we need prudence and progressiveness ».
Because of the variants?
“Not all of them should cause concern. Attention must be paid to those that can increase the transmission of the virus, cause more serious cases of disease or reduce the immune response of those who have recovered from Covid or have been vaccinated. We know that the English one, which is now 90% of the virus circulating in Italy, is more transmissible and probably leads to an increase in hospitalization ».
And the others?
“The latest ECDC surveillance studies suggest a possible increase in the risk of hospitalization for the population infected with the three variants and in some cases in the population under 60 even in intensive care”.
But do vaccines lose some of their effectiveness with these mutated forms of the virus?
“Compared to the English one, they work very well, while some a little less so with the South African one, which fortunately circulates very little in Italy. For the Brazilian the studies are in progress and for the Indian it is too early to tell ».
Recombinant protein vaccines are also on the way. Are they more or less effective than the current ones?
“They use proven technologies for the hepatitis B vaccine and we know that they offer an effective immune response, even if we have to wait for the EMA to finish evaluating the huge amount of experimental data that is subjected to its examination. I believe that the trial will be over by May ».
What does it say to those who are afraid of the recall with AstraZeneca?
“That the recommendations provided by Ema, Aifa and the Ministry of Health to continue with the same vaccine come from the continuous analysis of an incredible amount of data on possible specific risks”.
Who completed the vaccination course in February, when will they have to revaccinate?
«We still need time to evaluate the duration of the immune response generated by vaccines. As we go on, times get longer. Before the ECDC indicated the minimum duration of immunization at 6 months, but new studies raise the bar to 8 months and it is likely that it will eventually be set even higher. As soon as we have acquired more stable data we will know when to make the calls ».
Are salivary tests reliable?
«The molecular ones, which however must be processed in the laboratory, have a reliability equal to similar buffers. For do-it-yourself antigenic salivaries, sensitivity and specificity must be assessed: research in the diagnostic field is rapidly evolving and we will soon have even more sensitive salivary tests ».
Is it possible to imagine covid free restaurants, hotels and concerts with the green pass?
“It is certainly a very important tool for acquiring a degree of greater freedom in many contexts. But until the majority of the population is immunized we will have to live with the rules on spacing and masks. With vaccinations and respect for the rules we could find ever greater freedom even around the corner ». –