Leave your comments
Five years ago, an organization of people in Wuhan, China, fell to a virus never before detected in the world.
The germ had no name, nor did the disease it would cause. Ultimately, it sparked a pandemic that exposed deep inequalities in the global fitness formula and reframed public opinion on how to combat deadly emerging viruses.
The virus is still among us, although humanity has developed immunity through vaccines and infections. It is less fatal than at the beginning of the pandemic and is no longer among the main causes of death. The virus is evolving, which means scientists want to follow it closely.
We don’t know. Scientists think the most likely scenario is that it circulated in bats, like many coronaviruses. They think it then infected another species, probably racoon dogs, civet cats or bamboo rats, which in turn infected humans handling or butchering those animals at a market in Wuhan, where the first human cases appeared in late November 2019.
That’s a known pathway for disease transmission and likely triggered the first epidemic of a similar virus, known as SARS. But this theory has not been proven for the virus that causes COVID-19. Wuhan is home to several research labs involved in collecting and studying coronaviruses, fueling debate over whether the virus instead may have leaked from one.
It is a difficult clinical enigma to solve at times. That effort has been made even more complicated by political wrangling over the origins of the virus and what foreign researchers see as a resolution across China to hide evidence that could help.
The true origin of the pandemic may not be known for many years, or never.
Probably more than 20 million. The World Health Organization has said member countries reported more than 7 million deaths from COVID-19 but the true death toll is estimated to be at least three times higher.
In the U.S., an average of about 900 people a week have died of COVID-19 over the past year, according to the U.S. Centers for Disease Control and Prevention.
The coronavirus continues to age people further. Last winter in the United States, other people over the age of 75 accounted for approximately part of the country’s COVID-19 hospitalizations and in-hospital deaths, according to the CDC.
“We cannot talk about COVID in the past, since it’s still with us,” WHO director Tedros Adhanom Ghebreyesus said.
Scientists and vaccine manufacturers have broken records in the speed of producing COVID-19 vaccines that have saved tens of millions of lives around the world and were a step in returning life to normal.
Less than a year after China learned about the virus, the U. S. and British governments have legal vaccines made through Pfizer and Moderna. mRNA vaccines are a plus.
Today, there is also a more classic vaccine manufactured through Novavax, and some countries have tried other options. The rollout in poorer countries has been slow, however, the WHO estimates that more than thirteen billion doses of COVID-19 vaccines have been administered worldwide since 2021.
The vaccines are perfect. They do a smart job by preventing severe illness, hospitalization, and death, and have been shown to be very safe, with rare serious side effects. But coverage against a milder infection begins to decline after a few months.
Like flu vaccines, COVID-19 vaccines will need to be up-to-date to adapt to the ever-changing virus, contributing to public frustration over the need for repeat vaccinations. Efforts are underway to expand next-generation vaccines, such as nasal vaccines that researchers hope can better block infection.
Genetic changes called mutations happen as viruses make copies of themselves. And this virus has proven to be no different.
Scientists named these variants after Greek letters: alpha, beta, gamma, delta and omicron. Delta, which became dominant in the U.S. in June 2021, raised a lot of concerns because it was twice as likely to lead to hospitalization as the first version of the virus.
Then in late November 2021, a new variant came on the scene: omicron.
“It spread very rapidly,” dominating within weeks, said Dr. Wesley Long, a pathologist at Houston Methodist in Texas. “It drove a huge spike in cases compared to anything we had seen previously.”
But on average, according to the WHO, it causes a less serious illness than delta. Scientists believe this may be due in part to the fact that immunity has evolved through vaccination and infections.
“Since then, we continue to see those other omicron subvariants accumulate more mutations,” Long said. “Right now, everything is locked on this omicron branch of the tree. “
The omicron parent now dominant in the United States is called XEC and accounted for 45% of the variants circulating nationally during the two weeks ending Dec. 21, the CDC said. Existing COVID-19 drugs and the latest vaccine booster deserve to be effective against this virus, Long said, because “it’s really kind of a remix of variants that are already circulating. “
Millions of people remain in limbo with a sometimes disabling, often invisible, legacy of the pandemic called long COVID.
It may take several weeks to recover from a COVID-19 attack, but other people develop more persistent disorders. Symptoms that last at least 3 months, years, come with fatigue, cognitive disorders called “brain fog,” pain, and cardiovascular disorders, among others.
Doctors don’t know why only some people get long COVID. It can happen even after a mild case and at any age, although rates have declined since the pandemic’s early years. Studies show vaccination can lower the risk.
It’s also unclear what causes long COVID, complicating the search for treatments. A vital clue: More and more researchers are discovering that remnants of the coronavirus can persist in the bodies of some patients long after their initial infection, although this cannot be the case. all cases.
The Associated Press Health and Science Department receives reporting from the Howard Hughes Medical Institute’s Science and Education Media Group. AP alone is to blame for all content.
Thank you. Please check your inbox to confirm.
© 1996 – 2025 NewsHour Productions LLC. All rights reserved.
PBS is a 501(c)(3) nonprofit organization.
THANK YOU. Please your inbox to confirm.