COVID Turns 5: Facts and Remaining Mysteries About the Virus

Five years ago, a mysterious new virus emerged in Wuhan, China, marking the start of a global health crisis.

Initially nameless, the virus and the illness it caused would eventually ignite a global pandemic. The crisis laid bare stark inequities in the world's healthcare systems and transformed public perceptions about managing deadly emerging pathogens. Five years later the virus is widely known as COVID-19.

Why It Matters

The virus persists, but widespread immunity from vaccinations and prior infections has rendered it less lethal than in the pandemic's early stages. While it no longer ranks among the leading causes of death, its ongoing evolution demands vigilant monitoring by scientists.

COVID-19 has claimed the lives of an estimated 20 million people globally. While World Health Organization (WHO) member nations have officially reported over 7 million deaths, the true toll is believed to be at least three times higher, according to WHO estimates.

What To Know

However, COVID-19 has continued to claim lives at an average rate of about 900 deaths per week over the past year in the United States, according to data from the Centers for Disease Control and Prevention (CDC).

Older adults remain the most vulnerable to the coronavirus. During last winter in the U.S., individuals aged 75 and older represented nearly half of all COVID-19 hospitalizations and in-hospital deaths, according to the CDC.

COVID-19 Vaccines

Scientists and vaccine manufacturers managed to develop COVID-19 vaccines at record speed, saving tens of millions of lives globally. These vaccines became the cornerstone of efforts to restore normalcy.

Less than a year after China identified the novel virus, health regulators in the U.S. and U.K. approved vaccines developed by Pfizer and Moderna. These breakthroughs were made possible by years of prior research, including Nobel Prize-winning discoveries that were instrumental in advancing mRNA vaccine technology.

Today, vaccine options include a more conventional formula from Novavax, alongside other alternatives adopted in some countries. While distribution to lower-income nations lagged initially, the World Health Organization (WHO) estimates that over 13 billion COVID-19 vaccine doses have been administered worldwide since 2021.

While highly effective at preventing severe illness, hospitalization and death, COVID-19 vaccines are not without limitations. They have demonstrated strong safety profiles with only rare serious side effects, but their protection against mild infections diminishes after a few months.

Similar to flu vaccines, COVID-19 shots require regular updates to keep pace with the virus's constant evolution, fueling public frustration over repeated vaccinations. Researchers are exploring next-generation options, including nasal vaccines, which could potentially offer stronger protection against infection.

Mysteries

The origins of the virus remain unclear, though scientists believe it likely originated in bats. It is suspected to have jumped to another species—possibly raccoon dogs, civet cats or bamboo rats—before infecting humans. The initial human cases emerged in late November 2019, linked to a market in Wuhan where such animals were handled and butchered.

This transmission pathway is well-documented and was likely responsible for the first SARS epidemic. However, it remains unproven in the case of the COVID-19 virus. Adding to the uncertainty, Wuhan hosts several research labs specializing in coronavirus collection and study, sparking ongoing debate over whether the virus could have leaked from one of these facilities.

Determining the origins of the virus is a complex scientific challenge under any circumstances, but the task has been further complicated by political disputes and accusations from international researchers that China has withheld crucial evidence.

The exact origin of the pandemic may remain a mystery for years to come, and it's possible it will never be fully uncovered.

What People Are Saying

WHO director Tedros Adhanom Ghebreyesus said to The Associated Press: "We cannot talk about COVID in the past, since it's still with us."

In a statement released on Monday, WHO said: "As we mark this milestone, let's take a moment to honour the lives changed and lost, recognize those who are suffering from COVID-19 and long COVID, express gratitude to the health workers who sacrificed so much to care for us, and commit to learning from COVID-19 to build a healthier tomorrow."

What's Next

Like all viruses, the COVID-19 virus undergoes genetic mutations as it replicates, a natural process that has shaped its evolution. Scientists classified these virus variants using Greek letters—alpha, beta, gamma, delta and omicron.

The omicron subvariant currently dominating in the U.S., known as XEC, made up 45 percent of circulating strains during the two weeks ending December 21, according to the CDC.

This article includes reporting from The Associated Press.