COVID-19 Found in People’s Blood Months After Infection

Researchers have detected COVID-19 viral proteins in the blood of 25 percent of patients, even up to 14 months after the initial infection with SARS-CoV-2. This means that for some Long COVID patients, their symptoms could come from ongoing infection.

With the strongest evidence to date that pieces of the COVID-19 virus can go on living and actively replicating inside patients long after the initial infection, a new research study provides an important clue to Long COVID. In the paper, published in Lancet Infectious Diseases, a UC San Francisco/Harvard Medical School team found viral proteins from COVID in the blood of a quarter of patients over a year after their first infection. The team used a new ultra-sensitive blood test to detect SARS-CoV-2 viral proteins in the blood of 171 people who had been infected with COVID.