An Anchorage man was hospitalized with botulism after eating salmon that had been put in jars, according to a bulletin from the State of Alaska Epidemiology (SOE). The salmon had been improperly canned.
This is the first known case of foodborne botulism in Alaska associated with home-canned food, says the SOE.
“Historically, all previously identified cases of foodborne botulism in Alaska have been linked to consumption of traditionally prepared Alaska Native foods,” said the bulletin. “Elsewhere in the United States, foodborne botulism is primarily linked to consumption of home-canned foods.”
The patient reported that on August 19, 2019 at approximately 7:30 PM, he consumed home-canned salmon that tasted unpleasant. The salmon had not been reheated before being consumed. Upon awakening at 7:00 AM the next morning, he felt light-headed and thereafter developed dysarthria (weak speech muscles), blurred vision, and facial weakness. The patient subsequently developed difficulty breathing. At the emergency department, clinicians quickly suspected botulism poisoning because of the patient’s clinical presentation and suspicious food history.
The patient was admitted to the intensive care unit and received Botulism Antitoxin Heptavalent (A, B, C, D, E, F, G) – (Equine) shortly after admission, roughly 7 hours after initial symptom onset. He was intubated and received mechanical ventilation for approximately 39 hours. After 4 days of intensive care and a total hospitalization of 7 days, he was discharged to home and fully recovered.
The patient stated that he had caught the salmon around July 20 and had canned it around July 25. The fish was refrigerated before canning. The patient heated the fish overnight in a slow cooker (a pressure canner was not used). The cooked salmon was placed into jars. He said that about 5 days after canning, he first noticed that a jar was not fully sealed and had started to smell. It was refrigerated. In total, about 10 jars started to smell and were refrigerated. No other suspect foods were identified and nobody else had reportedly eaten the canned salmon.
The leftover salmon remaining in the consumed jar and the salmon in an unopened jar from the same batch were submitted to the Alaska State Public Health Laboratory (ASPHL) for testing.
Type E botulinum toxin was detected in the patient’s serum and in leftover fish from the consumed jar, and C. botulinum was detected in salmon from both jars and in gastric fluid. A stool sample from the patient was negative for both botulinum toxin and C. botulinum. The salmon submitted for testing plus approximately 15 additional jars of fish and one jar of caribou that had not been properly canned were decontaminated and disposed of by ASPHL.
This botulism case was caused by type E botulinum toxin, said the SOE, which has been associated with a lower case-fatality rate than type A toxin in Alaska.
“Type E botulism spores can withstand colder temperatures than other types of spores, and associated foodborne botulism cases typically involve consumption of fish or marine mammals. In contrast, most foodborne botulism cases in the Lower 48 are caused by toxin types A or B, and associated foodborne botulism cases typically involve consumption of contaminated vegetables (e.g., improperly canned vegetables),” the bulletin continued.
Given the relatively short incubation period (<12 hours) and rapid progression of illness associated with this case, the patient was fortunate to receive antitoxin within 7 hours of symptom onset. Early administration of antitoxin can prevent progression of illness and shorten its duration. In most of the United States, antitoxin can only be obtained by shipping it from CDC Quarantine Stations located in major airports around the nation. However, due to the high rate of foodborne botulism in Alaska, CDC allows federally-supplied antitoxin to be prepositioned at multiple Alaska hospitals for rapid administration.