Recent models and evidence from successful lockdowns suggest that behavioural changes can reduce the spread of COVID if most, but not necessarily all, people comply.
Two decades of pandemic war games failed to account for Donald Trump. Last week, the number of confirmed COVID infections passed 15 million globally, with around , deaths. Lockdowns are easing in many countries, leading some people to assume that the pandemic is ending, says Yonatan Grad, an epidemiologist at the Harvard T. If immunity to the virus lasts less than a year, for example, similar to other human coronaviruses in circulation, there could be annual surges in COVID infections through to and beyond.
Here, Nature explores what the science says about the months and years to come. The pandemic is not playing out in the same way from place to place. Countries such as China, New Zealand and Rwanda have reached a low level of cases — after lockdowns of varying lengths — and are easing restrictions while watching for flare-ups. Elsewhere, such as in the United States and Brazil, cases are rising fast after governments lifted lockdowns quickly or never activated them nationwide.
The latter group has modellers very worried. In South Africa, which now ranks fifth in the world for total COVID cases, a consortium of modellers estimates 2 that the country can expect a peak in August or September, with around one million active cases, and cumulatively as many as 13 million symptomatic cases by early November. Cinemagoers in Hangzhou, China, follow new norms of distancing and mask-wearing.
But there is hopeful news as lockdowns ease. Early evidence suggests that personal behavioural changes, such as hand-washing and wearing masks, are persisting beyond strict lockdown, helping to stem the tide of infections.
Researchers in virus hotspots have been studying just how helpful these behaviours are. Profile of a killer: the complex biology powering the coronavirus pandemic. However, the government lifted lockdown measures on 1 June and, rather than falling, the high number of weekly COVID deaths plateaued.
In regions where COVID seems to be on the decline, researchers say that the best approach is careful surveillance by testing and isolating new cases and tracing their contacts.
This is the situation in Hong Kong, for instance. He expects that the strategy will prevent a huge resurgence of infections — unless increased air traffic brings a substantial number of imported cases. Pandemic on campus: tell us how your institution is coping.
But exactly how much contact tracing and isolation is required to contain an outbreak effectively? Source: Data from ref. For now, mitigation efforts, such as social distancing, need to continue for as long as possible to avert a second major outbreak, says Bhatt.
It is clear now that summer does not uniformly stop the virus, but warm weather might make it easier to contain in temperate regions. In areas that will get colder in the second half of , experts think there is likely to be an increase in transmission.
Many human respiratory viruses — influenza, other human coronaviruses and respiratory syncytial virus RSV — follow seasonal oscillations that lead to winter outbreaks, so it is likely that SARS-CoV-2 will follow suit.
Evidence suggests that dry winter air improves the stability and transmission of respiratory viruses 8 , and respiratory-tract immune defence might be impaired by inhaling dry air, she adds. In addition, in colder weather people are more likely to stay indoors, where virus transmission through droplets is a bigger risk, says Richard Neher, a computational biologist at the University of Basel in Switzerland. According to Dr. David Hirschwerk , an infectious disease specialist with Northwell Health in Manhasset, New York, said while vaccination may be the way out of the pandemic, vaccine hesitancy, especially regarding children, makes him skeptical about the outcome.
Health officials and other experts have predicted that the pandemic will improve significantly by sometime next year. Experts say that although some of these predictions may prove accurate, factors like the United States reopening too soon this year and vaccine hesitancy could delay progress.
As coronavirus cases continue to rise throughout the United States — driven by the highly infectious Delta variant — many are wondering when this…. And yet, there is no shortage of fresh end-of-world prophecies for the coming year. The following predictions are now particularly trendy among doomsday enthusiasts:. If all this has got you worried, have a look at some of the more notorious doomsday scenarios in history that failed to materialize, just like hundreds of other prophecies through the ages.
While some of the listed events had tragic consequences for many involved, a look at the track record of prophets and prophecies is a good reminder that there is no need to panic. After all, predicting the end of days is a tricky business.
The end of the world was predicted to occur on December 21, , when one of the great cycles in the Mayan calendar came to an end. Faced with the wealth of alarmist information available on the world wide web, even NASA was compelled to publish an information page about why the world would not end on December 21, See our countdown to the end of the Mayan calendar.
The world was also supposed to end on October 21, Start with J. Richard Gott III. In , Gott was a physics undergraduate fresh out of Harvard, spending the summer in Europe. Demolition on the wall began 21 years later. This motivated Gott to write his method up. He published it in the journal Nature in There, Gott wrote of the future of humanity itself. He forecast a 95 percent chance that the human race would cease to exist within 12 to 18, years.
Not all Nature readers were convinced. Goodman complained in a letter to Nature. He has become a sort of scientific soothsayer, successfully predicting the runs of Broadway plays and when the Chicago White Sox would again win the World Series they did in Gott calls his prediction technique the Copernican method. Copernicus, the great Renaissance astronomer, asserted that the Earth is not the center of the universe.
Our sun is an ordinary star in an ordinary galaxy. This allows an order-of-magnitude estimate of the future duration.
Suppose you had visited the wall at the 25 percent point in the timeline. Or pretend you visited at the 75 percent point. Then the future would have been only one-third the past duration. This statement would have turned out to be true for anyone who visited the wall in the shaded part of the diagram. Gott made that prediction, except that he also made use of the knowledge that the wall was then eight years old. He reasoned that this prediction had a 50 percent chance of being right.
You may feel that 50 percent is too wishy-washy and Gott just got lucky. No problem: The method can supply predictions with any degree of confidence you choose.
This is less impressive, given the extremely wide range — but it would have been correct, too.
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