“It doesn’t prove that this new strain is in fact more infectious,” Gottlieb said on CNBC’s “Squawk Box.”
According to researchers at the Los Alamos National Laboratory, the new strain of the coronavirus started to spread in Europe in early February and then migrated to other parts of the world, including the U.S. By the end of March, this new strain became the dominant form of the virus in the U.S. and Canada.
“The analysis could be confounded by the fact that this just became the dominant strain in Europe because it got into Europe early and then got into the United States from Europe,” argued Gottlieb, the former head of the U.S. Food and Drug Administration. “It really doesn’t prove anything.”
Gottlieb said the study, which has not yet been peer reviewed, is only based on computational analysis and therefore more work needs to be done. “We don’t have any other data to support it, including cell culture data.”
“We saw a change like this with Ebola and we initially thought that it also made Ebola more contagious and we actually had cell culture data to support it at that time,” said Gottlieb, a CNBC contributor who sits on the boards of Pfizer and biotech company Illumina. “We found that when we put it into animal studies, in fact the change in the virus didn’t change its contours at all, didn’t make it more infectious.”
Pfizer is developing a vaccine. If the study were to be proven correct, it may complicate vaccine development.
The Los Alamos researchers said the mutation was of “urgent concern” because of the more than 100 vaccines in the process of being developed to prevent Covid-19. Some vaccine researchers have been using the virus’s genetic sequences isolated by health authorities early in the outbreak, which began late last year in China.
So far, the Los Alamos researchers have identified 14 mutations. Their analysis was assisted by scientists at Duke University and the University of Sheffield in England.
Gottlieb said there are different strains of the coronavirus circulating, but argued that mutation alone does not mean it is more contagious.
“Just because it mutates doesn’t mean it’s changing in ways that’s going to make it more virulent or more infectious,” he said. “It is going to drift over time. Generally the drift should be in the direction of making it less virulent, less dangerous, not more, if it’s selected for because it wants to keep its host alive.”
The study did not conclude that the new strain causes a more severe illness, based on a comparison of 447 people in Sheffield, England. Hospitalization rates for people with the original strain and the new strain “remained relatively constant across this time period,” researchers wrote.
There are nearly 3.7 million confirmed cases of Covid-19 across the world, according to Johns Hopkins University data Wednesday morning. Globally, 257,096 people have died. In the U.S., which has the most infections of any country, there are more than 1.2 million cases and at least 71,000 deaths.
— CNBC’s Berkeley Lovelace Jr. contributed to this report.