The findings “solve a long-standing question about a very serious disease in the ocean,” said Rebecca Vega Thurber, a marine microbiologist at University of California, Santa Barbara, who was not involved in the study.
It took more than a decade for researchers to identify the cause of the disease, with many false leads and twists and turns along the way.
Early research hinted the cause might be a virus, but it turned out the densovirus that scientists initially focused on was actually a normal resident inside healthy sea stars and not associated with disease, said Melanie Prentice of the Hakai Institute, co-author of the new study.
Other efforts missed the real killer because researchers studied tissue samples of dead sea stars that no longer contained the bodily fluid that surrounds the organs.
But the latest study includes detailed analysis of this fluid, called coelomic fluid, where the bacteria Vibrio pectenicida were found.
“It’s incredibly difficult to trace the source of so many environmental diseases, especially underwater,” said microbiologist Blake Ushijima of the University of North Carolina, Wilmington, who was not involved in the research.
He said the detective work by this team was “really smart and significant.”