In three separate incidents this summer, a nine-year-old Virginia boy, a 16-year-old Florida teen, and a Louisiana man in his early 20s all died after being infected with a rare “brain-eating amoeba.”

Now, the Centers for Disease Control and Prevention is asking for samples of Virginia waterways to try and develop a test for detecting deadly microscopic amoeba.

“It’s a terrible disease that we would like to know more about and be able to tell the public more about from a prevention standpoint,” said Michael Beach, the federal agency’s associate director for healthy water. “We are trying to learn more, but it’s a tough one because it’s such a rare occurrence.”

The Times-Dispatch reported that the Virginia boy’s case is the first amoeba death in Virginia since 1969.