An outbreak of type A botulism associated with a commercial cheese sauce.

BACKGROUND: Although botulism is rare, recognition of a possible case of this illness represents a public health emergency. To prevent more cases, prompt investigation must be done to determine whether illness is linked to commercial product or restaurant. Botulism can masquerade as other illnesses, and seemingly unlikely foods can harbor botulinum toxin. OBJECTIVE: To confirm the diagnosis and determine the cause and extent of an outbreak of botulism associated with food served at a delicatessen. DESIGN: Retrospective cohort study of patrons of the delicatessen; laboratory analysis of food, serum samples, and stool samples; and traceback of implicated food. SETTING: Community in Georgia. PARTICIPANTS: Patrons of the delicatessen. MAIN OUTCOME MEASURES: Botulinum toxin in food, serum, or stool and Clostridium botulinum in food and stools. RESULTS: 8 of 52 patrons (15%) met the case definition for botulism. In 4 of the 8 patrons, and illness other than botulism was initially diagnosed. Five of the 8 were hospitalized, and 1 died. Stool cultures from 4 patrons yielded type AC. botulinum, and two serum samples contained botulinum toxin. All ill persons ate food from the delicatessen on 1 October 1993. Of the 22 persons who ate at the delicatessen that day, all 8 ill persons but none of the 14 well persons ate a potato stuffed with meat and cheese sauce. An open can of cheese sauce contained type A botulinum toxin and yielded C botulinum on culture. Cheese sauce experimentally inoculated with C botulinum spores became toxic after 8 days at a temperature of 22 degrees C (room temperature). CONCLUSIONS: A commercial, canned cheese caused a botulism outbreak. This product readily becomes toxic when contaminated by C botulinum spores and left at room temperature. Mild botulism caused by unusual vehicles may be misdiagnosed. Botulism should be included in the differential diagnosis of persons with signs or symptoms of acute cranial nerve dysfunction.

Clinical and laboratory comparison of botulism from toxin types A, B, and E in the United States, 1975-1988.

Cases of adult botulism (n = 309) were studied to identify clinical differences between toxin types and to evaluate the sensitivity of diagnostic laboratory testing. Patients with illness from type E toxin had the shortest incubation periods. Sporadic case-patients were more severely ill: 85% required intubation compared with only 42% in multiperson outbreaks. Of patients with type A botulism, 67% required intubation compared with 52% with type B and 39% with type E. Toxin testing was positive for 40%-44% of serum and stool specimens obtained within 3 days of toxin ingestion and for 15%-23% of specimens obtained thereafter, while 37% of stool specimens obtained > 3 days after toxin ingestion were positive by culture. Patients with type A botulism have more severe illness. In general, specimens obtained early are more likely to be positive by toxin assay, and stool cultures are more sensitive than toxin detection for specimens obtained later in the illness.

Type F botulism due to neurotoxigenic Clostridium baratii from an unknown source in an adult.

Type F botulism was confirmed in a 54-year-old male with signs compatible with botulism who reported to the emergency unit of a hospital. Botulinal neurotoxin was detected in the patient's serum and fecal specimens, and a neurotoxigenic organism whose physiologic characteristics correspond to those of Clostridium baratii was isolated. The toxin produced by the isolate was neutralized by type F botulinal antitoxin and cross-neutralized with lower efficiency by type E antitoxin. The patient's food history was not suggestive of botulism, and it seems likely that the illness was due to colonization of the gut.

Laboratory findings in four cases of adult botulism suggest colonization of the intestinal tract.

There was laboratory evidence of intestinal colonization in four cases of adult botulism confirmed by the Centers for Disease Control. No performed toxin was detected in available foods, but Clostridium botulinum was isolated from foods in two instances. Botulinal toxin was detected in the sera of all four patients, in one case at 47 days after ingestion of suspected food. C. botulinum was demonstrated in the stool of all four patients and persisted for 119 days after the onset of illness in one patient. Two patients had surgical alterations of the gastrointestinal tract, which may have promoted the colonization. The apparent lack of ingestion of performed toxin in these cases and the persistence of botulinal toxin or C. botulinum, or both, for long periods in three of the patients suggest that colonization of the intestinal tract occurred.

Examination of feces and serum for diagnosis of infant botulism in 336 patients.

In the 12-year period 1975 to 1987, feces from 336 infants were examined for botulinal neurotoxin and Clostridium botulinum. All the infants had illnesses which prompted their physicians to consider infant botulism in the diagnosis. Stool specimens from 113 of the infants yielded organisms that produced botulinal neurotoxins assumed to be responsible for the illness. The types of botulinal toxin in the confirmed cases were distributed as follows: 38 A, 69 B, 2 atypical B, 1 E, 1 F, 1 A + B, and 1 B + F. The type A and B toxins in a single infant were produced by two different strains of organism, and the type B and F toxins in another infant were produced by a single strain. The physiological characteristics of all the isolated toxigenic organisms except two were consistent with those of group I (proteolytic) C. botulinum. The toxigenic isolate from the infant with type E botulism was identified as C. butyricum, and that from the infant with type F botulism was identified as C. barati. Toxin of the same type as produced by the isolated organisms was identified in feces of 98 of 111 culture-positive infants. Botulinal toxin was identified in the serum of 9 of 67 culture-positive infants (8 of 22 infants with type A organisms; 1 of 43 infants with type B organisms; neither of 2 infants with A + B or atypical type B organisms). Botulinal toxin was not detected in feces (206 infants) or in serum (114 infants) of the culture-negative infants. The culture-positive infants had clinical features and a course of illness consistent with those of infant botulism. Most of the culture-negative infants probably had illnesses other than botulism, but specimens might have been obtained late in some infants' illnesses, when the organism had disappeared.

Two cases of type E infant botulism caused by neurotoxigenic Clostridium butyricum in Italy.

The first two confirmed cases of type E infant botulism occurred in two 16-week-old girls in Rome, Italy. The original diagnosis for the first patient was intestinal blockage due to an ileocecal invagination, which was treated surgically. Postoperatively, the patient became unresponsive and required ventilatory assistance. A diagnosis of infant botulism was then made. The second infant presented to the same hospital 7 1/2 months later with profound weakness, hypotonicity, mydriasis, and areflexia. This case was recognized as possible botulism at admission. Both cases were confirmed by detection and identification of type E botulinal toxin in stool specimens and in enrichment cultures of those specimens. The toxigenic organisms isolated were quite different from Clostridium botulinum type E. The apparent causative organism in each case resembles Clostridium butyricum but produces a neurotoxin that is indistinguishable from type E botulinal toxin by its effects on mice and by its neutralization with type E botulinal antitoxin.

Characterization of an organism that produces type E botulinal toxin but which resembles Clostridium butyricum from the feces of an infant with type E botulism.

The apparent causative organism from the only reported case of type E infant botulism was isolated and characterized. Except for its ability to produce type E botulinal toxin, this organism (strain 5262) would be unquestionably identified as Clostridium butyricum. This is the second time an organism resembling a defined Clostridium species other than a member of the C. botulinum group has been implicated in infant botulism.

Isolation of an organism resembling Clostridium barati which produces type F botulinal toxin from an infant with botulism.

All reported cases of infant botulism except one have been caused by proteolytic strains (group I) of Clostridium botulinum, toxin types A or B. We describe the cultural and biochemical characteristics of the causative organism of this singular case of infant botulism, caused by type F botulinal toxin. Although this organism produces type F botulinal toxin, it is quite different from proteolytic (group I) C. botulinum, being more closely related to Clostridium barati.

Atypical toxin variant of Clostridium botulinum type B associated with infant botulism.

An atypical toxin variant of Clostridium botulinum (strain 657) was isolated from the feces of a 6-week-old female infant whose symptoms and clinical history were consistent with infant botulism. Toxin detected in the feces and the toxin produced by isolates from the feces and from two rectal swabs could be neutralized by type B botulinal antitoxin only at very high ratios of of antitoxin to toxin in the neutralization mixture. One international unit of type B antitoxin neutralized only about 10 lethal doses of 657 toxin as compared with approximately 10,000 lethal doses of conventional type B toxin from the Beans strain. Antitoxin prepared against 657 toxin was 10 times more effective against the conventional toxin than against the homologous toxin. Toxoid-antitoxin-binding studies indicate that both 657 toxin and type B toxin are heterogeneous and that both toxins may contain the same molecular variants, but that the proportions of the variants are different in each.

Selective medium for isolation of Clostridium botulinum from human feces.

A selective medium, Clostridium botulinum isolation (CBI) agar, was developed for the isolation of C. botulinum from human feces. This medium contains cycloserine (250 microgram/ml), sulfamethoxazole (76 microgram/ml), and trimethoprim (4 microgram/ml) as selective inhibitory agents. Qualitative tests indicated complete recovery of C. botulinum types A, B, F, and G on CBI medium. It was more difficult to recognize type G colonies on the medium because of their lack of lipase activity. Except for a few species of Clostridium, the growth of other obligate anaerobes and of the facultative anaerobes tested on CBI medium was suppressed. Quantitative studies of C. botulinum on the selective medium yielded counts comparable to those obtained on egg yolk agar control plates. Isolation of C. botulinum types A, B, and F from seeded fecal specimens was easily achieved with CBI medium. The use of CBI agar should aid the rapid isolation of C. botulinum from fecal specimens associated with foodborne and infant botulism.

Susceptibility of Clostridium botulinum to thirteen antimicrobial agents.

A total of 224 strains of Clostridium botulinum (including isolates from 14 patients with infant botulism and 4 with wound botulism) and 15 strains of C. sporogenes were tested by agar dilution for susceptibility to tetracycline, metronidazole, erythromycin, penicillin, rifampin, chloramphenicol, clindamycin, cephalothin, cefoxitin, vancomycin, sulfamethoxazole-trimethoprim, nalidixic acid, and gentamicin. At least 90% of the C. botulinum strains tested (except for nonproteolytic strains of toxin type F with penicillin) were susceptible to all drugs except sulfamethoxazole-trimethoprim, nalidixic acid, and gentamicin. Minimal inhibitory concentrations for strains from patients with infant and wound botulism were similar to those for other C. botulinum strains.

Production of phenylacetic and hydroxyphenylacetic acids by clostridium botulinum type G.

Phenylacetic and hydroxyphenylacetic acids were present as major acids in spent growth medium from Clostridium botulinum type G. These aromatic acids were identified by gas-liquid chromatography and mass spectrometry.

Cultural and physiological characteristics of Clostridium botulinum type G and the susceptibility of certain animals to its toxin.

Strain 89 of Clostridium botulinum type G, isolated by Gimenez and Ciccarelli in 1969, was characterized culturally, biochemically, and toxigenically. It was motile, hemolytic asaccharolytic, weakly proteolytic, lipase and lecithinase negative, and it produced acetic, isobutyric, butyric, and isovaleric acids in peptone-yeast extract-glucose broth. No spores were seen in smears from solid or liquid media. Very low levels of toxin were produced in regular broth cultures, but dialysis cultures yielded 30,000 mouse 50% mean lethal doses (LD50 per kg, orally and subcutaneously, respectively; and for guinea pigs, 10,000 to 20,000 and 100 mouse LD50 per kig, intragastrically and intraperitoneally, respectively.

Coproexamination for botulinal toxin and clostridium botulinum. A new procedure for laboratory diagnosis of botulism.

Stool or serum specimens or both from 318 persons pertaining to 165 botulism investigations over a three-year period were examined. Botulinal toxin was detected in stools of 19 of 56 patients and in sera of 20 of 60 patients with clinical botulism; it was not detected in specimens from 246 persons with an illness other than botulism or well contacts of patients. Clostridium botulinum was identified in stools of 36 of 60 clinical botulism patients and in four of 27 asymptomatic contacts of patients with botulism victims, but not in stools of 65 persons not associated with confirmed botulism. When stool and serum samples were examined, confirmatory evidence was obtained for 72.9% of the botulism cases. Detection of botulinal toxin or C botulinum in the stool of a persons should be considered evidence supporting the clinical diagnosis of botulism.