Several studies have found that the proportion of SARS-CoV-2 coronavirus reinfection is between 1% and 10% among individuals immunized from the Covid vaccine or previous natural infections. Although in most cases they have no symptoms, there is still a risk that they can spread the virus in the community. Therefore, experts emphasized the importance of speeding up vaccination campaigns and complying with anti-infectious laws and regulations until a large part of the population is immunized.
The results of clinical studies show thatEffectiveness God Coronavirus disease vaccine Approved by the European Medicines Agency for emergency use (EMA) And the Italian Medicines Agency (FIFA) Are variable: Although cold numbers cannot be compared for many reasons, they range in 66% Single dose Johnson people 95% There are about the following messenger RNA vaccines Pfizer-BioNTech E Hyundai NIAID.This effect refers to freedom from symptom of Coronavirus disease.This means that many vaccinated people will not only develop typical symptoms of infection, but also part of the infection while remaining Asymptomatic.Fortunately, vaccine protection is Almost always Against this risk Hospital stay E deathHowever, infected people who have been vaccinated (and cured) can still spread the virus in the community.Since we are still far away from the place where we dream of vet Herd immunityIn fact, we may never reach it. Coronavirus can reach the risk of unprotected people, so there is a risk of contracting coronavirus. complication The life threat is still high.For this reason, until most people are not vaccinated, they must continue to comply Social isolation And put on mask.
According to several surveys Quoted in Spanish newspaper El Pais, The situation in which an infection occurredOne percent and ten percent Among those who have been immunized, “depends on time, population, research location and vaccination schedule.”In most cases, these people are positive people Molecular buffer, But asymptomatic, thanks to the immune barrier guaranteed by the immunity triggered by the vaccination or the previous vaccine Natural infection. As Professor Guillermo López Lluch, Professor of Cell Biology at Pablo de Olavide University (UPO), pointed out, these patients can continue to infect the virus in the body for a certain period of time and spread it to other people. The risk: for those who have not been vaccinated. According to the vaccination chart of “Data World”, so far, Italy has received 32.4 million doses of Covid vaccine, but only 10.9 million people are fully immune (equivalent to 18.1 million of the total population).
I learn”SARS-CoV-2 infection after vaccination among health care workers in California“An article published in the authoritative scientific journal “The New England Journal of Medicine” found1.19% University of California San Diego and 0.97% Students from the University of California, Los Angeles: all receivedmRNA-12731 -NIAID or Suitability Provided by Pfizer-BioNTech. In the article “COVID reinfection is rare-but it can still help the virus spread“Published in Nature and Articles”So far, what we know about covid-19 reinfectionIn the British Medical Journal. Therefore, a certain proportion of mainly asymptomatic vaccinators and cured patients can continue to spread the virus, and with the vaccination coverage rate still limited, this may be a problem that should not be underestimated. “Because these cases do not produce symptoms in most cases, these cases are likely to be more than those found. Therefore, these people who are considered to have been immunized will not undergo PCR tests.” There is dichiarato for El Pais Mark Pandori, director of the Nevada Public Health Laboratory.
Professor Lluch said that another problem may be Variations of interest Characteristic is bigger Transitability, Such as that English variant B.1.17 And the second Indian variant (50-60% more contagious than the first variant). The virus can use these mutations to continue to spread easily among people, even among immunized people.It should also be borne in mind that some studies have found several cases Re-infection between young people; For example, a survey of 200 Marines found that they would be infected by 10% after natural infection. “The SARS-CoV-2 seropositivity among healthy young people and subsequent The risk of infection: a prospective cohort study” is the same. Since the younger population will be the last to be vaccinated, scientists recommend extra caution and at least wait until a large proportion of the population is immunized before canceling anti-virus measures, such as masks and spacing.