Botulism from chopped garlic: delayed recognition of a major outbreak.
Diagnosis of botulism in two teenaged sisters in Montreal led to the identification of 36 previously unrecognized cases of type B botulism in persons who had eaten at a restaurant in Vancouver, British Columbia, during the preceding 6 weeks. A case-control study implicated a new vehicle for botulism, commercial chopped garlic in soybean oil (P less than 10(-4)). Relatively mild and slowly progressive illness, dispersion of patients over at least eight provinces and states in three countries, and a previously unsuspected vehicle had contributed to prolonged misdiagnoses, including myasthenia gravis (six patients), psychiatric disorders (four), stroke (three), and others. Ethnic background influenced severity of illness: 60% of Chinese patients but only 4% of others needed mechanical ventilation (P less than 10(-3]. Trypsinization of serum was needed to show toxemia in one patient. Electromyography results with high-frequency repetitive stimulation corroborated the diagnosis of botulism up to 2 months after onset. Although botulism is a life-threatening disease, misdiagnosis may be common and large outbreaks can escape recognition completely.
St Louis
M E
ME
Enteric Diseases Branch, Centers for Disease Control, Atlanta, Georgia.
Peck
S H
SH
Bowering
D
D
Morgan
G B
GB
Blatherwick
J
J
Banerjee
S
S
Kettyls
G D
GD
Black
W A
WA
Milling
M E
ME
Hauschild
A H
AH
D001905:Botulinum Toxins / Q000097:blood; D001906:Botulism / Q000150:complications / Q000453:epidemiology / Q000208:ethnology / Q000209:etiology*; D001955:British Columbia; D002681:China / Q000208:ethnology; D004196:Disease Outbreaks; D005511:Food Handling; D005737:Garlic / Q000009:adverse effects*; D006801:Humans; D009422:Nervous System Diseases / Q000209:etiology; D010946:Plants, Medicinal; D012131:Respiratory Insufficiency / Q000209:etiology; D012147:Restaurants; D013029:Space-Time Clustering; D013696:Temperature
D001905:Botulinum Toxins