Coronavirus: MLB Reveals COVID-19 Antibody Test Results


The coronavirus epidemic has largely spared the world of baseball, with data released Sunday to prove it.

Of the 5,603 major league employees who have undergone what the researchers have called the largest national antibody study to date, only 60 have tested positive, the researchers said on Sunday.

The researchers announced an estimated positive rate of 0.72% after adjusting the results for what they called false positives and false negatives.

Angels’ employees had the highest positive rate among the 26 teams that participated, but the relatively small number of tests administered to each team – 123 for Angels – made it difficult to draw conclusions, said lead researcher Jay Bhattacharya, professor of medicine at Stanford. He said the rate of positive tests among Angel’s employees was lower than the infection rate in the local community.

Yet the tiny percentage of positive tests has provided a data point as scientists determine the extent of the coronavirus in the United States. Bhattacharya said he expected a higher positive rate.

“The epidemic has not gone far,” he said. “We have a long way to go. “

However, in other antibody studies limited to specific regions, positive rates ranged from 2.8% in Santa Clara County to 24.7% in New York. The Major League Baseball study researchers noted that their participants were not representative of the general population: 95% under the age of 65, 80% white, 60% male and 100% employees.

“What we are seeing is an indication of a socio-economic gradient,” said Bhattacharya.

Antibody tests verify the presence of proteins produced by the body in response to the virus, not the presence of the virus itself. Scientists have not determined the level of immunity that antibodies could provide and the duration of that immunity.

But by providing evidence of the spread of the virus, antibody studies offer useful data to authorities on how to reopen cities and states.

The false positives and false negatives of these and other antibody tests offer a warning to employers – not just MLB – when reopening workplaces. The researchers said that one test, either for antibodies or for the active virus, would produce enough false positives to require more than one test to certify that a person is safe to return to work.

The researchers did not identify the number of players who participated in the tests, who were volunteers. They pointed out that the MLB offered assistance from a public health perspective, not advice to get baseball back on the field.

The owners are expected to present players with a shortened season proposal this week, with an opening day scheduled for early July. Although the researchers were able to isolate the study results based on geography, they said that the participants on each team were too few to advise the league on the safest places to return.

“To say, look, you can go play in Arizona or anywhere based on this study would be difficult,” said Bhattacharya. “I would have designed the study very differently if I tried to answer this question.”


Please enter your comment!
Please enter your name here