The National Institutes of Health released a study Tuesday, showing new evidence the Coronavirus was in the U.S. as early as December 2019.
The study looked at 24,000 stored blood samples donated between Jan. 2 and Mar. 18, 2020.
It found samples from people in Illinois, Massachusetts, Mississippi, Pennsylvania and Wisconsin tested positive for COVID-19 antibodies as early as Jan. 7.
Because it takes 14 days on average for antibodies to develop, researchers believe those blood samples are from people who tested positive for the virus before Christmas 2019.
In other COVID-19 news:
- The European Union recommended lifting restrictions on United States travelers for the first time since the pandemic began.
- Tokyo is hoping to start allowing 10,000 people to start attending mass events, potentially including the 2021 Olympic Games, once the state of emergency covering most of Japan is lifted this weekend.