The thinking prevalent among American public health experts and scientists has changed. Now, they think it’s unlikely United State Achieve the so-called “Herd immunity“against Covid-19, The point at which enough people will be protected virus So that the country gets rid of the disease.
The new prediction is that the virus will likely continue to spread in the United States in the coming years, but it will be possible to manage the threat and allow it to return to normal. Therefore, hospitalizations and deaths will continue to occur. However, the numbers will be much lower than those recorded at the start of the pandemic.
Conclusions from the experts heard by The New York Times. Although the country has vaccinated half of its adult population with at least one dose of immunity, there is consensus that herd immunity will not be achieved in the near future. Some estimate that this will never be possible.
It is not yet known how much the hospitalizations and deaths from the Coronavirus will decrease in the country. This depends, according to experts, on the progress of vaccination in the United States and the rest of the world, in addition to the evolution of the virus itself.
Coronavírus, covid-19 – Foto: Gerd Altmann / Pixabay
As more and more mutations are recorded in other areas, they explain that a vaccination sequence, especially for people at higher risk, will be necessary to reduce the severity of outbreaks and even the recurrence of new waves of infection. .
“It is unlikely that the virus will disappear,” Rustam Antia, a biologist at Emory University in Atlanta, said in an interview with The New York Times. “But we want to do as much as possible for that [a covid-19] Become a mild infection. ”
A change in perspective is a new challenge for health authorities. The search for herd immunity captured the public’s imagination. Saying that this goal will not be achieved adds another reason skeptics have not received the vaccination.
Anthony Fauci, Chief Adviser to President Joe Biden’s government on COVID-19, acknowledged the shift in thinking among experts. That is why, he says, the White House has stopped using the term “herd immunity.”
He told the “New York Times”: “People were confused and thinking that we would never reduce infection until we reach this mysterious level of herd immunity, no matter what that number.” “What I’m saying is, forget it for a second. If you vaccinate enough people, it will calm down.” Infection. ”
At the start of the pandemic, experts said herd immunity could be achieved if around 60% to 70% of the country’s population were immunized against the virus. Most experts, including Fauci, expected the United States to reach this level as soon as vaccines became available.
However, as vaccination speeds up in the country, estimates are starting to rise. That’s because the calculations were based on the transmissibility of the original version of the virus. Variant B.1.1.7, from the UK, now prevalent in the USA, is 60% more contagious.
As a result, some experts now estimate that herd immunity can be achieved with 80% of the protected population. However, they indicated that the emergence of more contagious variables could cause a new adjustment in the forecast. It is still necessary to consider the possibility of immunized people transmitting the virus.
Research shows that 30% of the American population is still reluctant to get vaccinated. This number is expected to improve as the campaign progresses, but may not be sufficient to achieve collective immunity.
“It is theoretically possible that we could reach 90% vaccine coverage, but I’d say it’s very unlikely,” said Mark Lipsitch, an epidemiologist at Harvard School of Public Health.
In addition to vaccine resistance, the regional dimensions of the United States are another factor that hinders the search for herd immunity. “The transmission of the disease is local,” Lipsitch said. If coverage is 95% in the United States as a whole, but 70% in some small cities, the virus doesn’t care. He will make his way in this city. ”
Global connectivity also underscores the need to promote a more equal vaccination campaign between countries, according to experts. Recent data from the World Health Organization (WHO) shows that the richest countries concentrate more than 80% of the vaccines applied so far.
“We will not achieve mass immunity as a state or state or even as a city until we have adequate immunity in the population as a whole,” said Lauren Ansell Myers, director of the Statistical Modeling Consortium at the University of Texas.
