A unique COVID-19 virus that spread through Chicago appears to link directly to an early outbreak in China and might not spread as easily and as rapidly as the virus prevalent in New York and elsewhere in the United States, according to new research.
In a preliminary study of genetic makeup of the coronavirus in Chicago, Northwestern University Feinberg School of Medicine researchers discovered a unique type that is more likely to be found in Chicago than in other parts of the country.
The aim from understanding the genetic difference in virus outbreaks better is to use that to develop effective vaccines.
After studying the genetic makeup of dozens of virus samples of nearly 90 people, the Northwestern researchers determined there were three main types of the virus found in Chicago.
Almost 60 percent of the samples studied were closely related to the virus that is prevalent in New York, which has been traced to Europe.
Thirty percent of the samples belonged to a virus type largely unique to Chicago, which is closely related to the virus from China, the study found. It notes that the second confirmed case in the United States was in Chicago, after a woman traveled in Wuhan, China.
Fewer than 10 percent of the samples were of a type closely aligned with the virus in Washington state, lead investigator Dr. Egon Ozer said.
“This is one of the first studies we’re aware of that is able to show these different groups,” Ozer said. “Does it mean it will transmit more frequently or more easily to people? We don’t know that. But this kind of study starts us looking in that direction.”
The research, which is preliminary and hasn’t been peer-reviewed, suggests that not all variations of the virus act the same, according to Ozer. Early findings suggest that the virus prevalent in New York might spread to people through the nose and throat at a higher rate than the virus that is unique to Chicago.
The research is giving scientists clues about different characteristics of the infections, though they caution that more research is needed.
“These differences might help us understand where a vaccine might be most effective,” Ozer said. “Wherever those differences are, this is a potential weakness in the virus.”
The study was done by collecting virus samples from COVID-19 tests for 88 patients in March. The genetic material was compared with 4,000 genetic samples from across the country and abroad collected in a research database.
Brett Chase’s reporting on the environment and public health is made possible by a grant from The Chicago Community Trust.