A researcher’s lifelong investigation of the botulinum bacteria
Millions of juvenile salmon died mysteriously in hatcheries across the Northwest from 1979 to 1982. Bankruptcy loomed for seafood companies as fish wobbled around the hatchery tanks and then expired.
Eventually, they brought in Mel Eklund ’55, a microbiologist and pathogen expert with the National Marine Fisheries Service in Seattle. His wife, Helen, had seen a news report about the dying salmon and when she told him, Eklund got to work.
He analyzed the fish samples in his lab and discovered what he suspected: The salmon were poisoned with botulism, one of the most powerful toxins in the world. Some of the hatcheries’ rearing ponds had earth bottoms where the C. botulinum bacteria had grown and produced the neurotoxin in dead juvenile fish. These fish in turn would get buried in pond sediments where live salmon cannibalized them, says Eklund. “On a warm day around 70 degrees, one dead fish contained enough toxin to kill 70 others.”
He trained hatchery managers on proper handling of the fish and corpses, and the following year, “They had so many fish, they had to truck them out.”
Eklund received the Gold Medal Award from the U.S. Department of Commerce for his work. It was just one recognition for Eklund’s work and discoveries, particularly with the bacteria that cause botulism. Over his 35-year career with NMFS, scientists and regulatory agencies from around the world applauded Eklund’s efforts in understanding and controlling this toxic danger.
Botulism is a paralytic illness caused by C. botulinum bacteria. Fortunately, the neurotoxin is destroyed by chlorine in municipal water systems and also by heat. The spores of this bacteria are often found in freshwater and marine sediments and in soil. Botulism in humans is relatively rare. Eklund and his NMFS lab researched botulinum, making a number of key discoveries and helping the seafood industry control this bacteria.
Eklund grew up in the tiny town of Saco, Montana, but when his mother died he moved to Chehalis, where he became involved with FFA. Thanks to his FFA leader, Eklund visited and then attended Washington State College, majoring in animal husbandry and pledging with the Alpha Gamma Rho fraternity.
When Eklund’s advisor realized he didn’t know about spoilage bacteria, he steered Eklund into a microbiology class, which fascinated him. His enthusiasm led to a 1957 master’s degree at WSC in food science and microbiology, and then to Purdue University for a doctorate in the same field. Eklund credits WSC professors John V. Spencer and William Stadelman with his success.
Although he studied microbiology, Eklund says he had no interest in working with C. botulinum after a professor took them to the U.S. Army quartermaster lab in Chicago. “They were working with botulism, and I thought, ‘I’m never going to work with that. It’s too dangerous,’” he says.
That changed after Eklund went to work for the NMFS in 1961. In the 1960s, botulism in packaged smoked fish and canned tuna sickened people in the Midwest, which led to surveys around the world to determine incidences of botulinum bacteria. Eklund’s lab analyzed marine and freshwater environments from Alaska to southern California for that study, which led to some discoveries.
Strains of C. botulinum are designated Type A through G based on the neurotoxin produced and split into groups based on whether they can digest proteins (proteolytic) or not (nonproteolytic). During the survey, Eklund isolated nonproteolytic Type F for the first time. He also determined that it could grow at lower temperatures than previously believed, thriving as low as 38°F.
Other findings caught Eklund’s attention. “During the incident study, I got interested in bacteria that look like botulinum but wouldn’t produce toxin,” says Eklund. He explains that his lab found for the first time that bacterial viruses called bacteriophages govern lethal toxin production in Types C and D botulinum.
His findings—published in the journal Science, with a follow-up study in Nature—opened a new line of research. Letters from prominent genetics researchers, such as Nobel Prize winning microbiologist Joshua Lederberg, praised the significance of Eklund’s work in understanding how C. botulinum produces toxins.
Laboratories and companies applied Eklund’s research to produce specific antigens and antitoxins to help protect animals from the disease.
Later, Eklund confirmed the first case of infant botulism in Seattle in 1978. He developed protocols for Alaska Natives to control bacterial pathogens in smoked and dried salmon. Eklund also developed and patented a selective and differential medium for the isolation of pathogen Listeria monocytogenes.
Eklund says the recommendations from his lab for time, temperature, and salt levels in processed seafood are still FDA requirements.
He retired from the NMFS in 1996, but continued consulting with seafood companies. Eklund received the WSU Alumni Achievement Award in 1998. He still keeps busy at the Seattle home he built and his 51-acre farm near Chehalis. He has two daughters, Cheryl Eklund and Lynda Eklund.