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How the pandemic ends



Manhattan.

Manhattan. Spencer Platt / Getty Images

New cases, hospitalizations and deaths are falling sharply. What will it take to announce the victory over COVID-1

9? Here’s everything you need to know:

Is the end near?
Virologists are cautiously optimistic that by the end of the summer, COVID-19 cases and deaths in the United States will fall so dramatically that life will return to normal. Today, 135 million Americans – more than half of all adults – are fully vaccinated, and in 10 states, 70 percent have received at least one dose. The Centers for Disease Control estimates that 100 million Americans have acquired some immunity from coronavirus infections (including asymptomatic). As a result, the pandemic is already showing “exponential decay”. This is a rapid decline in transmission that occurs when the virus can find a few new vulnerable people. New cases are declining by more than 90 percent from the January peak of 250,000 a day and are still declining. Pfizer and Moderna vaccines show amazing real effectiveness against serious illness and death by 99 percent, and warm weather allows more Americans to spend time outdoors, where transmission is drastically less likely. By August, the average daily deaths from COVID, which are now around 500, could fall below 100 – roughly the same daily deaths from seasonal flu. “Things will look very good this summer,” said Christopher Murray, director of the Institute for Health Indicators and Evaluation at the University of Washington. “A lot of people will think it’s over. But what happens in the fall is the tricky part.”

Why so?
In the United States, differences in regional vaccines are growing, so there is a high risk of exacerbation of COVID when the weather gets colder. Less than 40 percent of Americans in many southern states have received at least one shot, compared to 65 to 70 percent of New England residents. By the fall, children will return to personal training, many families will hold large indoor gatherings, and immunity developed from previous infections may not provide full protection against options. There have been reports from India and Brazil of people who have already suffered from COVID after having relapsed with variants, and the United Kingdom is becoming ill in cases caused by the Indian strain.

Is herd immunity possible?
This is unlikely for the country as a whole. Because the British version, which is now circulating in the United States, is estimated to be 60% more contagious, most virologists now estimate that about 80% of Americans will need immunity from previous infections or vaccinations to achieve classical herd immunity. where the transmission stops. Mark Lipsic, an epidemiologist at Harvard School of Public Health TH Chan, warns that “the disease is transmitted locally” and may continue in some areas with lower vaccination rates. “If the coverage is 95 percent in the United States as a whole, but 70 percent in a small town, the virus doesn’t matter,” he explained. “He will make his way through the small town.”

Are the options important?
The Pfizer, Moderna, and Johnson & Johnson vaccines appear to provide stable protection against known variants, but studies have shown that they may be 10 to 20 percent less effective. And as the virus continues to spread to much of the world, it can develop new mutations and variants that make vaccines less effective. So far, less than a quarter of the world’s population is infected and many poor countries are not expected to have widespread access to vaccines by 2023.

Can COVID be eradicated?
Only one infectious disease, smallpox, has ever been eradicated, after two centuries of inoculation and a concerted 14-year global vaccination campaign in the 1960s and 1970s. SARS-CoV-2, the virus that causes COVID, has been shown to mutate rapidly, so epidemiologists say it is difficult to predict how long immunity from previous infections and vaccinations will last. Booster photos may be needed. In a survey of the magazine Nature, almost 90 percent of immunologists, infectious disease researchers and virologists believe that the disease will become endemic and circulate in the pockets of the world’s population in the foreseeable future.

What does this mean?
“We will define the virus instead of defeating it,” Lipsic said. This happened with the Spanish flu, which evolved from a deadly disease to normal seasonal flu as the human immune system gained experience in fighting it. There is a good chance that COVID-19 will become less deadly over time, as natural selection favors virus strains that do not kill their hosts; if infected people are alive and walking, they can infect more people. Virologists expect COVID-19 to reappear among the unvaccinated, especially in the winter, but over time it will become more like a common cold – causing runny nose, congestion, a feeling of exhaustion. (About 20 percent of colds are caused by four different types of coronaviruses that have long been circulating in humans.) SARS-CoV-2 is likely to join a long list of viruses we just have to live with. “As the old saying goes,” says Dr. Ashish K. Jha of Brown University, “pandemics end with whining, not crashing.”

The Spanish flu is not gone
The Spanish flu has never disappeared. Known as the “mother of all pandemics,” the flu kills up to 100 million people worldwide and infects a third of the world’s population in two years, but by the 1920s it had lost most of its virulence. Instead of disappearing, the original virus mutated into strains that are the direct ancestor of modern influenza viruses. “You can still find the genetic traces of the 1918 virus in the seasonal flu that is circulating today,” said researcher Jeffrey Taubenberger. He led a team of scientists who in the late 1990s obtained the genetic signature of the Spanish flu by extracting viral RNA from autopsied lung samples from American soldiers and a woman from Alaska whose body was preserved in permafrost. When the descendants of the Spanish flu combined with bird flu or swine flu viruses, creating a new strain, they caused deadly new pandemics, including 1957 and 1968 (1 million people died each in each) and the swine flu pandemic. 2009, which killed 300,000. “We still live in what I would call the ‘1918 pandemic era,’ 102 years later,” Taubenberger said, “and I don’t know how long it will last.”

This article was first published in the latest issue of The week magazine. If you want to read more like this, you can try six risk-free issues of the magazine here.


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