FILE – A medical worker takes a swab sample from a worker of the China Star Optoelectronics Technology (CSOT) company during a round of COVID-19 tests in Wuhan in central China’s Hubei province, Aug. 5, 2021. (Chinatopix via AP, File)
![FILE – People attend an exhibition on the city’s fight...]()
FILE – People attend an exhibition on the city’s fight against the coronavirus in Wuhan in central China’s Hubei province, Jan. 23, 2021. (AP Photo/Ng Han Guan, File)
![FILE – This undated electron microscope image made available by...]()
FILE – This undated electron microscope image made available by the U.S. National Institutes of Health in February 2020 shows the Novel Coronavirus SARS-CoV-2, yellow, emerging from the surface of cells, pink, cultured in the lab. Also known as 2019-nCoV, the virus causes COVID-19. The sample was isolated from a patient in the U.S. (NIAID-RML via AP, File)
![FILE – Cemetery workers in protective gear bury a person...]()
FILE – Cemetery workers in protective gear bury a person alongside rows of freshly dug graves at the Vila Formosa cemetery in Sao Paulo, Brazil, April 1, 2020. (AP Photo/Andre Penner, File)
![FILE – Dr. Sydney Sewall fills a syringe with the...]()
FILE – Dr. Sydney Sewall fills a syringe with the COVID-19 vaccine at the Augusta Armory, Dec. 21, 2021, in Augusta, Maine. (AP Photo/Robert F. Bukaty, File)
![FILE – Denmark’s Jonas Vingegaard, left, and teammate Matteo Jorgenson,...]()
FILE – Denmark’s Jonas Vingegaard, left, and teammate Matteo Jorgenson, of the U.S., wear face masks to protect themselves from the Corona virus prior to the start of the fourteenth stage of the Tour de France cycling race over 151.9 kilometers (94.4 miles) with start in Pau and finish in Saint-Lary-Soulan Pla d’Adet, France, July 13, 2024. Several riders had to abandon the race after contracting COVID-19. (AP Photo/Daniel Cole, File)
![FILE – Nancy Rose, who contracted COVID-19 in 2021 and...]()
FILE – Nancy Rose, who contracted COVID-19 in 2021 and exhibits long-haul symptoms including brain fog and memory difficulties, pauses while organizing her desk space, Jan. 25, 2022, in Port Jefferson, N.Y. (AP Photo/John Minchillo, File)
FILE – A medical worker takes a swab sample from a worker of the China Star Optoelectronics Technology (CSOT) company during a round of COVID-19 tests in Wuhan in central China’s Hubei province, Aug. 5, 2021. (Chinatopix via AP, File)
ExpandScientists still aren't clear where it came from, and they are still trying to understand what causes long-term symptoms called long COVID.
