Emily Chan
Samples from the deer were extracted and sent to the Washington Animal Disease Diagnostic Laboratory (WADDL) for testing.
“When we received the samples, the eyes appeared highly abnormal,” Fisk said. “Usually, when you cut into the eye, it contains clear fluid, but in this case, it was filled with thick, reddish-brown debris. The other interesting thing was the retina was detached, and there was significant inflammation and necrosis.”
Plague is incredibly rare, but the deer’s symptoms were similar to cases seen in Wyoming and Oregon, so the researchers decided to test for plague to rule it out.
They used a polymerase chain reaction test to analyze small amounts of DNA. It confirmed the deer suffered from the plague.
The plague was only detected in the deer’s eye samples, not in any organs or tissues. It is unclear why that is, but the researchers suspected that the bacteria from the plague may have already cleared from the other tissues by the time the samples were gathered and examined.
It is a challenge to determine how prevalent ocular plague in deer is because infected animals will likely die from natural causes or fall prey to predators before humans run into them.
“It’s probably just a super rare finding that anyone came across this animal before it died in the wild,” said Dr. Kyle Taylor, a pathologist at WADDL.
After testing, the samples were destroyed for safety purposes, and the case was reported to the Centers for Disease Control and Prevention.
