People vaccinated with mild coronavirus infections may also have Covid-19 long with problems with the heart, brain or lungs, among other parts of the body, according to a study published Wednesday in the journal Nature Medicine.
The research, carried out by scientists at the Washington University School of Medicine in St. Louis (USA) and the St. Louis, warns that, despite the existence of vaccines, more tools are needed against the virus.
The study, made with data from more than 13 million cases, concluded that being vaccinated against the Sars-CoV-2 virus reduces the risk of death by 34% and the risk of developing long-term Covid by 15%.
It also showed that vaccines are effective in preventing some of the most worrisome manifestations of long-term Covid (lung and blood clotting disorders), which have declined by 49% and 56%, respectively, among those vaccinated.
However, while vaccines remain vitally important in the fight against Covid, “they provide only modest protection against long-term Covid,” explains Ziyad Al-Aly, the study’s first author and a clinical epidemiologist at the University of Washington.
Therefore, “now that we know that Covid can have persistent health consequences, even among those vaccinated, we must move towards developing mitigation strategies that can be implemented in the long term, because it doesn’t look like Covid is going to disappear anytime soon,” complements Al-Aly.
Such strategies may include nasal vaccines – more effective and potent than current ones – or other types of vaccines or drugs aimed at minimizing the risks of long-term Covid.
“Getting Covid-19, even among vaccinated people, seems almost inevitable today”, warns Al-Aly, who points out that between 8% and 12% of vaccinated people can develop long-term Covid.
In the future, the disease “is likely to leave large numbers of people with chronic and potentially disabling conditions that go untreated, affecting not only their health but also their ability to work, life expectancy, productivity and social well-being.” the investigator advances.
Since the beginning of the pandemic, more than 524 million people worldwide have been infected with the virus; of them, more than 6 million died, more than a million in the United States alone.
The study, of 13 million affected, mostly older white men, did not include data related to the Omicron variant that began to spread rapidly in late 2021.
Patients were classified as fully vaccinated if they had received two doses of the Moderna or Pfizer-BioNTech vaccines or one dose of the Johnson & Johnson/Janssen vaccine, as booster doses had not yet been given at the time of the survey.
Among other findings, the study confirmed that in addition to complications in the heart, brain and lungs, persistent Covid also causes disorders in the kidneys, blood clotting, mental health, metabolism, and the gastrointestinal and musculoskeletal systems.
In addition, the analysis of 3,667 vaccinated and hospitalized patients with the most severe cases of Covid showed that they had a 2.5 times greater risk of dying than people hospitalized with the flu.
They also had a 27% increased risk of long-term Covid in the first 30 days after diagnosis compared to 14,337 people who were hospitalized with seasonal flu.
The researchers also compared long-term health outcomes with a pre-pandemic control group of more than 5.75 million people (and who never had Covid because it did not yet exist) and found that those who had Covid faced significantly more risk. death and heart, lung, neurological and kidney disease.
“The constellation of findings shows that the burden of death and illness experienced by people with advanced Covid-19 infections is not trivial,” concluded the author.