The probable case of paralytic shellfish poisoning at Kenai Peninsula's Clam Gulch overnight Sunday was the first ever recorded at the popular Southcentral clamming area, and the second-most northern probable case of the toxin ever reported in Alaska, state officials said Tuesday.
On Sunday, a Kenai resident harvested razor and possibly butter clams -- also known as surf or pink-neck clams, according to Department of Fish and Game sport fish biologist Mike Booz -- and ate the clams later that day. The person became ill overnight , and suffered "classic" paralytic shellfish poisoning symptoms of vomiting, headache, shortness of breath, tingling around the mouth and a floating sensation.
It's the first probable case of paralytic shellfish poisoning ever reported at Clam Gulch, said Dr. Michael Cooper, infectious disease program manager with the state Division of Public health, with records on the beach ranging back to the 1980s.
Paralytic shellfish poisoning is caused by eating shellfish contaminated with toxin-producing dinoflagellate algae. The dinoflagellate are reddish-brown in color and can cause red streaks to appear in the ocean, called "red tides," according to the U.S. Centers for Disease Control and Prevention .
Most reports of paralytic shellfish poisoning in occur in Southeast, lower Southcentral areas such as Kodiak, and Southwest Alaska, Cooper said. There's only one other probable case of paralytic shellfish poisoning from a more northern locale, recorded in Nome earlier this year, Cooper said. A resident had eaten crab in a broth and became sick with the classic symptoms, but later urine analysis and samples of the broth came back negative. However, enough time had passed between the urinalysis that the negative testing "doesn't rule it out," Cooper said, and the broth may not have contained the toxin present in the crab.
While reports on paralytic shellfish poisoning vary from year to year, Cooper said the "vast majority" of cases likely go unreported. Between 2002 and 2011, there were 41 confirmed and probable cases of paralytic shellfish poisoning, but more than half of those cases were during a 2011 outbreak in Southeast Alaska. The last confirmed case of paralytic shellfish poisoning in the Kachemak Bay area, southeast of Clam Gulch, occurred in the 1970's, Cooper said.
"Every year it's hit or miss," Cooper said.
Cook Inlet has largerly been isolated from reported cases of paralytic shellfish poisoning, Booz said. Still, "our message is that you consume at your own risk," he said.
Clam Gulch is famous for the razor clams harvested from the beach adjacent to the state recreation area, according to the Alaska Division of Parks and Outdoor Recreation .
Booz said that aerial surveys estimated that several hundred people were digging clams on the beach on both Friday and Saturday. There were "definitely plenty of people around," he said.
Most people digging razor clams do so near to the beach's access point, Booz said. However, the Clam Beach area ranges north to the Kasilof River, and south to the Ninilchik River, Booz said. The area where the probable case of poisoning occurred on Sunday was listed in a press release as 1.5 miles "down the beach, near the big tower," which Booz identified as a nearby cell phone tower.
Between 2010 and 2012, roughly 330,000 razor clams were harvested on the east side of the Kenai Peninsula, between the community of Anchor Point to the Kasilof River, Booz said.
While all beaches where shellfish are harvested commercially are regularly tested for the toxin, there's no widespread testing of beaches where Alaskans harvest shellfish recreationally. The sheer number of miles of Alaska's coastline "makes it impossible for any agency to go out and test every beach," said Ty Keltner, spokesperson for the Department of Environmental Conservation.
In 2012, the DEC's recreational shellfish monitoring pilot program began testing some popular sites around the state. Last year the Kachemak Bay Research Reserve began testing Clam Gulch shellfish through the program, Booz said.
Last summer, all shellfish tested out of Clam Gulch tested negative for the toxin, Booz said. This year's testing had just begun, with razor and surf clams harvested over the weekend and sent into the DEC's Anchorage office for testing this week.
Fish and Game personnel were returning to Clam Gulch on Tuesday to collect more razor clams for testing, Booz said, following Sunday's report of possible poisoning.
Testing of recreationally harvested shellfish takes roughly five days, said Matthew Forester, a DEC official.
Paralytic shellfish poison can be present in all locally harvested shellfish, including clams, mussels, oysters, geoducks and scallops, according to the state Division of Public Health . Early warning signs of paralytic shellfish poisoning include a tingling of the lips and tongue. The toxins can cause fatalities in as little as two hours.
There's no cure or "anti-toxin" for paralytic shellfish poisoning, Cooper said. There's also no way to clean or cook the toxin out of shellfish, and toxins can be present in shellfish in varying amounts on the same beach, according to the Division of Public Health. Cooper recommended that people who develop symptoms go to their health care provider for monitoring.
The last reported fatalities "likely related" to paralytic shellfish poisoning occurred in the 1990s, when two people died, Cooper said.
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