For almost two years, scientists had been cautiously relieved that a deadly viral outbreak blamed for the deaths of scores of Atlantic bottlenose dolphins up and down the East Coast had not reached the Keys.
That tepid calm ended this week.
A necropsy performed on an Atlantic bottlenose dolphin that died on Nov. 7 after washing up sick on the Bahia Honda State Park beach earlier that day returned positive Tuesday for morbillivirus -- a measles-like disease that is highly contagious among sea mammals.
According to federal fisheries scientists, this means the outbreak area of the virus, which has killed 1,569 dolphins from New York to Central Florida since July 2013, now includes the Atlantic side of the Keys. And the entire Gulf of Mexico and Florida Bay side of Florida is now considered a "surveillance area" for the outbreak, said Laura Engleby, a biologist and chief of the National Oceanic and Atmospheric Administration's southeast marine mammal branch.
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"It takes a little while to run the tests to confirm morbillivirus," Engleby said in a phone interview Tuesday. "We suspected it was morbilli, but we wanted to wait to say it until we were absolutely 100 percent sure, and now we are."
Until now, the furthest south a morbillivirus case associated with the current outbreak reached was in the Indian River Lagoon in Brevard County. The first confirmed case there was in October 2013. There have since been about 10 dolphins found in the area infected with morbillivirus.
Despite the concern over the Keys case, there is no elevation in the number of strandings associated with this outbreak. In fact, scientists have noticed a slowdown in strandings nationwide, especially from Georgia to New York. Northern Florida strandings are still considered elevated, however.
The Keys are home to several captive marine mammal facilities where dolphins are kept in enclosed lagoons supplied with seawater directly from the ocean.
Since morbillivirus is so contagious, NOAA has informed the U.S. Department of Agriculture, the federal agency with jurisdiction over marine mammal parks, that morbillivirus is now in the Keys.
The virus affects marine mammals' lungs, neurological systems and immune systems. There has never been a case a human catching morbillivirus from a marine mammal, Engleby said. But associated byproduct illnesses can be passed, and that is why scientists are warning people not to touch stranded mammals they might see on the beach. People should also not let their pets approach sick mammals.
The few dolphins and whales with morbillivirus that scientists find alive usually show signs of respiratory problems, brain damage and other illnesses that result from their weakened immune systems caused by the disease. They are usually in such bad shape that veterinarians euthanize the mammals even before tests are conducted.
"Mammals suspected of having morbillivirus are not candidates for rehabilitation," Engleby said.
NOAA scientists began worrying the latest outbreak could spread to the Keys earlier this year. They based their concerns off a case in 1990 when 290 dolphins died from the disease in the Gulf of Mexico.
NOAA biologists theorize those mammals could have had the same strain that killed 742 dolphins on the East Coast from August 1987 to April 1988. This would indicate an outbreak could inflict damage for years before dying out.
Allison Garrett, a NOAA spokeswoman, said anyone seeing a sick or stranded whale or dolphin should call (877) 942-5343. There is also a smart phone app for reporting marine mammal strandings that can be downloaded at http://1.usa.gov/1b1kqfv.