Five years ago, a cluster of people in Wuhan, China, fell sick with a virus never before seen in the world.
The germ didn’t have a name, nor did the illness it would cause. It wound up setting off a pandemic that exposed deep inequities in the global health system and reshaped public opinion about how to control deadly emerging viruses.
The virus is still with us, though humanity has built up immunity through vaccinations and infections. It’s less deadly than it was in the pandemic’s early days and it no longer tops the list of leading causes of death. But the virus is evolving, meaning scientists must track it closely.
Where did the SARS-CoV-2 virus come from?
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’s a difficult scientific puzzle to crack in the best of circumstances. The effort has been made even more challenging by political sniping around the virus’ origins and by what international researchers say are moves by China to withhold evidence that could help.
The true origin of the pandemic may not be known for many years — if ever.
How many people died from COVID-19?
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 affect older adults the most. Last winter in the U.S., people age 75 and older accounted for about half the nation’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.
What vaccines were made available?
Scientists and vaccine-makers broke speed records developing COVID-19 vaccines that have saved tens of millions of lives worldwide – and were the critical step to getting life back to normal.
