The microscopic pathogens looked familiar. There was Salmonella, for example, a bacteria found in poultry and associated with food poisoning in people who eat tainted eggs, fruits, or vegetables. There was Staphylococcus, including a type common on human skin but which, if inhaled, can cause pneumonia. And there were startling fungi—weird not because of what they were, but because of where they were found.
(From National Geographic / By Craig Welch)– Scientists didn’t find these microbes in human blood or in something living inside a barn. They were found in the exhaled breath of killer whales that move between Monterey Bay, California, and British Columbia’s Queen Charlotte Islands.
Researchers trying to understand why an endangered population of orcas along North America’s West Coast has dropped to a mere 78 individuals have uncovered another way human beings may be harming cetaceans: infectious disease.
In a new study last week of the West’s southern resident killer whales, scientists captured infectious agents not typically associated with whales in exhalations from the animals’ blowholes. Some of these pathogens were even antibiotic-resistant. That led scientists to suspect these orcas may increasingly be exposed to dangerous microbes that are being flushed into coastal waterways by storm runoff or sewage.
“These animals spend a fair amount of time in ecosystems close to urban environments,” says Brad Hanson, who oversees orca recovery for the National Oceanic and Atmospheric Administration. “Because of runoff, either directly or indirectly, there are a variety of things that may be getting into their system.”
The study, published Friday in Scientific Reports, was the result of several years of sampling of whales and waters around the San Juans, a cluster of small islands near the border between the United States and Canada. Scientists tested waters they call the sea-surface microlayer, the tiny film of fluid on top of the sea where marine waters meet air, some small part of which they assumed would be captured when a whale exhaled.
Read the full article here: http://news.nationalgeographic.com/2017/03/human-diseases-pacific-orcas-killer-whales-salmonella/