Officially, the first case of Covid-19 was detected on January 21, 2020, in a Washington state man that had recently traveled from Wuhan, China
New data is changing what we know about the Covid-19 timeline. A blood sample analysis taken from 24,000 Americans suggests that Covid-19 was possibly circulating in the US undetected earlier than was previously thought.
On January 24, 2020, the first two known cases of Covid-19 in Illinois were reported. A woman who had traveled from Wuhan, China contracted the virus and passed it on to her husband. They both fully recovered after treatment at St. Alexius Medical Center in Hoffman Estates.
ABC7 Chicago spoke to the woman's husband, Tom Panocha, last January. "They just did a real good job taking care of me," Panocha said. "They treated me like a person, not an illness. It was almost two weeks before I found out that I had it and I really didn't think I was sick."
New evidence shows Covid-19 could have been in Illinois earlier than thought
However, new evidence suggests Tom Panocha and his wife were not the first Covid-19 cases in Illinois.
A recent study by the journal Clinical Infectious Diseases found coronavirus antibodies from seven individuals in the US much earlier than was reported. Three of the participants were from Illinois. The others were from Massachusetts, Mississippi, Pennsylvania, and Wisconsin.
One of the participants from Illinois was infected on Christmas Eve or earlier, according to the study's lead author, Keri Althoff, an associate professor at the Johns Hopkins Bloomberg School of Public Health.
It's not known exactly where in Illinois the three participants that tested positive for Covid-19 were located. But experts seem to be increasingly in agreement that Covid-19 in the US was circulating several weeks before the previously thought timeline of mid-January 2020.
The blood samples were taken as part of an ongoing study that tracks 1 million Americans over the years to research health.
CDC found evidence Covid-19 was in the US in December 2019
This recent study builds on further evidence from the Centers for Disease Control and Prevention (CDC) that showed coronavirus antibodies detected in participants' blood as early as December 2019.
Previously, the CDC had announced that the novel coronavirus began to spread throughout the US during a three-week period starting in mid-January.
Natalie Thornburg principal investigator of the CDC’s respiratory virus immunology team said, “The studies are pretty consistent. There was probably very rare and sporadic cases here earlier than we were aware of." She continued, "But it was not widespread and didn’t become widespread until late February,” said Thornburg,
Thornburg believes this new information emphasizes the importance of countries working together to identify emerging health threats such as the emergence of new viruses.
Why are some experts cautious about the new information?
Covid-19 is a form of coronavirus, otherwise known as a common cold. People with antibodies to the common cold can sometimes produce false positives when testing for the novel coronavirus antibodies of SARS-CoV-2.
Researchers used multiple tests to avoid false-positive results. But it is possible these early cases were caused by the common cold, and not the Covid-19 virus.
Why is it important to determine how Covid-19 began to spread?
By understanding exactly how the new coronavirus gained a foothold in the US and how it began to spread so quickly once it did, health experts can learn how to be ready, and hopefully, prevent the next viral outbreak.
Researchers with the University of California Los Angeles found that a spike in hospitalizations on the West Coast could mean Covid-19 began circulating there around Christmas 2019. Dr. Joann Elmore, professor of medicine at UCLA said, "We may never truly know if these excess patients represented early and undetected COVID-19 cases in our area.”
Dr. Elmore added, “But the lessons learned from this pandemic, paired with health care analytics that enable real-time surveillance of disease and symptoms, can potentially help us identify and track emerging outbreaks and future epidemics.”