After the brutal summer surge caused by the highly contagious delta mutant, the coronavirus has receded again.
In the United States, about 90,000 new infections are recorded daily, a decrease of more than 40% since August. Hospitalizations and deaths are also decreasing.
The crisis isn’t everywhere, and the situation in Alaska is particularly dire, but trends are clear nationwide, raising expectations that the worst is finally behind us.
Over the past two years, pandemics have struck the country like waves, flooded hospitals, and then retreated, but returned after Americans were alert.
It is difficult to distinguish why the virus is so declining and flowing, and it is even more difficult to predict the future.
But as winter approaches, there are optimistic reasons. About 70% of adults are fully vaccinated, and many children under the age of 12 may be eligible for injections within a few weeks. Federal regulators may soon approve Covid-19’s first antiviral drug.
Dr. Nahid Badelia, director of the Center for Emerging Infectious Diseases Policy Research at Boston University, said:
But the pandemic isn’t over yet, scientists warned. Nearly 2,000 Americans are still dying every day, and another winter surge is plausible. Given how many Americans remain unvaccinated and how much remains unknown, they said it was premature to abandon basic precautions.
“We repeated this many times, but it was too early to take our feet off the pedals,” said Dr. Badelia. “We’re trying to reach that finish line, so we need to be a little more careful.”
When the first wave of cases struck the United States in early 2020, there was no Covid vaccine and essentially no one was immune to the virus. The only way to flatten the proverbial curve was to change individual behavior.
That was the purpose of the first round of stay-at-home orders, business closures, mandatory masks, and a ban on large gatherings. While there is still debate as to which of these measures was most effective, many studies have collectively suggested that people stayed home, curtailed an increase in the number of cases, and made a difference. I am.
Researchers say these policies, coupled with voluntary social distance, are likely to have helped end the initial surge.
Jennifer Nuzzo, an epidemiologist at Johns Hopkins University, said:
Eventually, the case will reoccur and a similar pattern will occur. Businesses and local governments will re-enforce regulations, and those who are re-entering the world will bend over and mask.
For example, the percentage of Americans who reported going to bars and restaurants or attending major events during the surge last winter surveyed an average of 44,000 Facebook users every day since April 2020. According to the US Covid-19 Trends and Impact Survey. ..
“Curves are shaped by public consciousness,” said Dr. Nuzzo. “We are lurking between crisis and self-satisfaction.”
Delta arrived during a period of severe pandemic fatigue, the moment many vaccinated Americans finally felt relaxed. The data suggest that the new variant did not cause more serious behavioral changes than the previous wave.
According to the Institute for Health Metrics at the University of Washington, in mid-July, only 23% of Americans said they always wear masks in public, the lowest percentage since March 2020. ..
By August 31, the peak of the delta wave, that number had risen to 41%, well below 77% of those who reported wearing masks during the winter surge.
“Just looking around, people are far more than normal or pre-Covid life,” said Dr. Christopher Murray, director of the institute.
Still, even the slightest changes in behavior can help slow down communication, especially in combination, and Delta has driven changes at both the individual and organizational levels. Schools have adopted new precautions, businesses have postponed reopening, and organizations have canceled the event, reducing the chances of the virus spreading.
Meanwhile, warmer autumn weather has arrived, allowing Americans in many parts of the country to socialize outside where the virus is unlikely to spread.
“We are in the shoulder season, cooler in the south than in the middle of summer and warmer in the north than in the middle of winter,” he said. David O’Connor, a virologist at the University of Wisconsin-Madison.
In fact, many of today’s virus hotspots, from Alaska to Minnesota, are at the northernmost tip of the country, and when temperatures are even colder, people can return to the country.
Behavioral changes are a temporary, short-term way to reduce cases.The true end of the pandemic comes from immunity..
The delta wave was the first major national surge that occurred after the vaccine became widely available and provided substantial protection against the virus for many adults. (Delta also probably led more Americans to be vaccinated.)
At the same time, the subspecies is so infectious that it spread rapidly throughout the vulnerable population, immunizing many unvaccinated Americans.
Neither vaccination nor pre-infection provides complete protection against the virus, but they dramatically reduce the chances of catching the virus. So by September, the virus had a lot of trouble finding a kind host.
Jeffrey Sherman, an infectious disease epidemiologist at Columbia University, said:
The fact that the number of cases is declining does not mean that the country has reached herd immunity. This is a goal that many scientists currently believe cannot be achieved. However, increased levels of vaccination and infection, coupled with milder behavioral changes, may have been sufficient to end the surge.
Joshua Salomon, an infectious disease expert and modeler at Stanford University, said:
In fact, scientists have said that a combination of factors that can differ in different parts of the country ultimately determines when and why the virus declines.
“Various waves and waves depend on the size of the previous wave, the number of people vaccinated, and the different varieties when school reopens,” said Alessandro Vespignani., Director of the Network Science Institute at Northeastern University in Boston.
In particular, some degree of randomness is also involved, as a small number of “super spreaders” appear to play a disproportionate role in the occurrence of outbreaks. Christina Ramirez, a biostatistician at the University of California, Los Angeles, said:
What you need to know about Covid-19 booster shots
The FDA has approved booster shots for a specific group of people who received a second dose of the Pfizer-BioNTech vaccine at least six months ago. The group includes: Pfizer recipients over the age of 65 or living in a long-term care facility. Adults at high risk for severe Covid-19 due to underlying illness. Healthcare workers and other people whose work puts them at risk. People with weakened immunity are eligible for a third dose of Pfizer or Moderna four weeks after the second injection.
Regulators have not yet approved booster shots for recipients of Moderna and Johnson & Johnson vaccines, but the FDA panel has …