A young Florida male dolphin was spotted in a Dixie County canal in March. Residents of the area have found dolphins trapped between the pier posts and the seawall. The University of Florida School of Veterinary Medicine, which leads the university’s marine animal rescue program.
By the time rescuers arrived, the dolphin was dead, he said. A team of routine autopsies collected various samples from the dolphins and stored them until they could be analyzed in more detail.
At the time, scientists had no reason to suspect bird flu had invaded the dolphins and were in no particular hurry, said Dr. Walsh, who collaborated with veterinary pathologist Dr. Robert Osiboff on the investigation. Both Andrew Allison, Veterinary Virologist, University of Florida School of Veterinary Medicine.
When the results came back this summer, they revealed signs of inflammation in the dolphin’s brain and surrounding tissue, Dr. Walsh said. Scientists have previously documented brain inflammation in fox kits infected with the virus, which can cause neurological symptoms in birds and mammals.
Subsequent laboratory testing detected Eurasian H5N1 in the dolphin’s brain and lungs. “Brain tissue actually showed high levels of virus,” Dr. Walsh said.
It’s unclear whether the virus contributed to the dolphin’s death, and it’s unclear how the animals became infected. But it’s not hard to imagine juvenile dolphins checking for sick birds near shorelines, Dr. Walsh said, adding: So if he comes across a sick, dying or dead bird, he may be very curious about it.