Question

On 18 January 2001, the Alaska Division of Public Health was informed by a local physician of a village in southwest Alaska where 14 people became ill after eating fermented beaver tails and paws on 17 January. Approximately 20 hours after the meal, 3 of the 14 had symptoms including dry mouth, blurry vision, and general weakness. Two patients developed respiratory failure and required mechanical ventilation. They subsequently were evacuated to an intensive-care unit (ICU) in Anchorage. Two patients recovered without further complications, The third required tracheotomy tube placement and mechanical ventilation for 1 month. Of the other 11 exposed persons, 4 reported minor symptoms, including dry mouth and nausea.

Beavers are hunted in southwest Alaska and certain parts are often fermented and eaten later. In traditional fermentation, food is kept in a grass-lined hole in the ground or a wooden barrel sunken into the ground or is placed in a shady area above the ground for several weeks to months. Since the 1970s, however, plastic or glass containers have been used and fermentation has been done above ground or indoors. In this outbreak, the tail and paws have been wrapped in a paper rice sack and stored for up to 3 months in the entry of a patient’s house. Some of the beaver tails and paws had been added to the sack as recently as 1 week before they were eaten. Clinical specimens from the 14 exposed people were tested at the Centers for Disease Control and Prevention (CDC) laboratory. Serum specimens from two of the ICU patients and in stool from the third were positive of a neurotoxin. The toxin was also detected in three beaver paws from the implicated meal.

Bacteria were cultured from the fermentation containers. The cultures grew only under anaerobic conditions. Laboratory tests indicated a bacterium as the causative agent.

1. What was the etiological agent of the outbreak?
2. What was the source of the disease?
3. What is the most likely cause of death of victims of this disease, which was seen in several patients from this outbreak?
4. What is a common source of this pathogen that avoided by infants to prevent transmission in that susceptible population?

Answer 1

1. Etiological agent of the disease is bacteria Clostridium botulinum.

2. The fermentated meal was the source of the disease as it have spores of bacteria.

3. The most likely to death of victim is the neurotoxin that is produced by Clistridium botulinm known as botox.

4. Common source of this pathogen is improper canning techniques that are used to store fermented foods.