[Botulism in infancy]

According to international references the publication ascertains the etiologic role of neurotoxin producing Clostridial spp., other than C. botulinum in Infant botulism. Authors report on the first Hungarian case of Infant botulism. The organism isolated -- C. barati -- is responsible only for a small proportion of published cases. Authors point out the conjunction of Infantile botulism and crib death.

Botulism: the present status of the disease

The main form of human botulism throughout the world is the classic foodborne intoxication. Would botulism is very rare, and most of the documented cases have been found in the United States. While infant botulism remains rare throughout the world, it has become the most frequent form of the disease in the United States in recent years. On very rare occasions botulism results from growth and toxin production in humans other than infants. Botulism occurs in animals with much higher frequency. The causative organisms constitute a diverse group of clostridia, resulting in nomenclature problems. Human botulism is largely limited to toxin types A, B, and E, while type C botulism predominates in avian and nonhuman mammalian species. The diagnosis of botulism is made on the basis of the neurologic signs and symptoms that it causes in humans and animals. The diagnosis is confirmed by tests that identify the toxin and toxigenic organisms in patient and food specimens. Treatment includes supportive intensive care and use of therapeutic antitoxin.

Application of PCR to a clinical and environmental investigation of a case of equine botulism

PCR for the detection of botulinum neurotoxin gene types A to E was used in the investigation of a case of equine botulism. Samples from a foal diagnosed with toxicoinfectious botulism in 1985 were reanalyzed by PCR and the mouse bioassay in conjunction with an environmental survey. Neurotoxin B was detected by mouse bioassay in culture enrichments of serum, spleen, feces, and intestinal contents. PCR results compared well with mouse bioassay results, detecting type B neurotoxin genes in these samples and also in a liver sample. Other neurotoxin types were not detected by either test. Clostridium botulinum type B was shown to be prevalent in soils collected from the area in which the foal was raised. Four methods were used to test for the presence of botulinum neurotoxin-producing organisms in 66 soil samples taken within a 5-km radius: PCR and agarose gel electrophoresis (types A to E), PCR and an enzyme-linked assay (type B), hybridization of crude alkaline cell lysates with a type B-specific probe, and the mouse bioassay (all types). Fewer soil samples were positive for C. botulinum type B by the mouse bioassay (15%) than by any of the DNA-based detection systems. Hybridization of a type B-specific probe to DNA dot blots (26% of the samples were positive) and PCR-enzyme-linked assay (77% of the samples were positive) were used for the rapid analysis of large numbers of samples, with sensitivity limits of 3 x 10(6) and 3,000 cells, respectively. Conventional detection of PCR products by gel electrophoresis was the most sensitive method (300-cell limit), and in the present environmental survey, neurotoxin B genes only were detected in 94% of the samples.

Polymerase chain reaction for detection of Clostridium botulinum types A, B and E in food, soil and infant faeces

The application of the polymerase chain reaction (PCR) for detection of Clostridium botulinum types A, B and E in foods, environmental and clinical samples was evaluated and compared to the mouse bioassay. Samples inoculated with 10, 100 and 1000 spores of Cl. botulinum types A and B included pasteurized milk, UHT milk, infant formula, infant faeces, meat juice, canned tuna, mushrooms, blood sausage and soil. Clostridium botulinum type E spores were inoculated into fish eggs, canned tuna, picked herring, raw fish and soil at similar levels. Spores were added to 2.5 g of each sample with the exception of soil which was inoculated in 10 g samples. The presence of Cl. botulinum in sample enrichments was determined by both PCR and the bioassay. An overall correlation of 95.6% was observed between PCR results and the mouse bioassay. Of the total of 114 samples tested there was disparity between the mouse bioassay and the PCR in three samples of soil inoculated with 100 type A or E spores and 10 type B spores per 10 g, respectively, and two samples of infant faeces inoculated with 10 type A or B spores per 2.5 g. All of these samples gave negative animal results and positive PCR results.

Landfill sites, botulism and gulls

Botulism due to Clostridium botulinum type C causes considerable mortality in gulls in the UK, and refuse disposal sites are suspected as a major source of toxin. C. botulinum types B, C and D were each found in 12 (63.2%) of 19 landfill sites examined. Type E was detected in only one (5.2%) and types A, F and G were not found. The prevalence of type C spores was much higher than that demonstrated in the UK environment by earlier surveys. The presence of these spores, together with the rotting organic matter and generated heat associated with landfill sites, undoubtedly leads to bacterial proliferation and toxigenesis. This is likely to result in botulism in scavenging gulls unless skilled landfill management prevents the ingestion of toxic material. Type D spores were previously shown to be rare in the UK environment and their high prevalence on landfill sites was therefore surprising. Four composite samples of refuse collected before distribution on a landfill gave negative results for C. botulinum and it seems likely that the gulls themselves play a major role in introducing contamination.

Type C botulism in turkeys: determination of the median toxic dose

The median toxic dose (TD50) of type C botulinum in turkeys was determined using an up-and-down method for toxicologic testing. Birds were dosed intravenously with 10, 20, or 40 mouse lethal dose per kilogram body weight (MLD/kg) of type C botulism toxin and observed for 5 days. Administration of toxin resulted in acute death, posterior paresis, or no effect, depending upon the dose. The TD50 causing posterior paresis was calculated as 25.75 MLD/kg (confidence interval = 17.08-38.82 MLD/kg). Posterior paresis was identified as the principal sign associated with sublethal botulism toxicosis in turkeys. The resultant posterior paresis was similar to the clinical syndrome observed in an unsolved field investigation.

Sequence of the gene coding for the neurotoxin of Clostridium botulinum type A associated with infant botulism: comparison with other clostridial neurotoxins

The neurotoxin gene from a strain of Clostridium botulinum type A causing infant botulism was cloned as a series of overlapping polymerase chain reaction (PCR) fragments generated using primers designed to conserved regions of published botulinal toxin (BoNT) sequences. Translation of the nucleotide sequence derived from cloned PCR fragments demonstrated that the toxin gene encodes a protein of 1,296 amino acid residues. Comparative alignment of the derived infant BoNT/A sequence with those of other published neurotoxins revealed highest sequence relatedness with BoNT/A of classical food-borne botulism. The sequence identity between infant and classical BoNT/A was 94.9% for the light chain (corresponding to 23 amino acid changes) and 87.1% for the heavy chain (corresponding to 109 amino acid changes).

Infant botulism: a review in South Australia (1980-89)

Between March 1980 and March 1989 there were six identified cases of infant botulism. The presenting symptoms were predominantly poor feeding, lethargy and constipation, and the presenting signs were predominantly hypotonia, weak gag reflex and respiratory difficulty. All required intensive care and prolonged hospital stays. Recovery was eventually complete in all cases. Infant botulism is an uncommon condition but early recognition with adequate intensive care usually results in complete recovery.

Effect of pH on the stability of type-C toxin of Clostridium botulinum

Stability of type-C botulinum toxin at pH 1.8-12.0 and during exposure to 5 and 28 degrees C for 20 and 16 h, respectively, was tested by titration on adult mice. The toxin was found in the samples kept at pH of 2.7-10.2, whereas, at the pH extremes of 1.8 and 12.0, it was inactivated.

Clostridium botulinum and sudden infant death syndrome: a 10 year prospective study

It has been proposed that sudden and unexpected death in infants due to intestinal infection with Clostridium botulinum may mimic the clinicopathological features of sudden infant death syndrome. Between 3.3 and 3.8% of infants in some series have had this neurotoxin-producing bacterium isolated on faecal culture. Prospective screening of 248 infants presenting with the sudden infant death syndrome to the Adelaide Children's Hospital over a 10 year period from 1981 to 1990 was conducted. Faecal samples were obtained from both small and large intestines and cultured specifically for C. botulinum. No samples were positive. The results of this study suggest that routine post-mortem culture of faeces for C. botulinum has been of limited use within the South Australian infant population over the last decade, and that occult botulism has not been a significant factor in the causation of sudden death.

Clostridium botulinum toxins: a general review of involvement in disease, structure, mode of action and preparation for clinical use

The neurotoxins produced by Clostridium botulinum are the most potent acute toxins known and are the causative agents of the neuroparalytic disease botulism. The toxins act primarily at peripheral cholinergic synapses by blocking the evoked release of the neurotransmitter acetylcholine. There are seven distinct serotypes of toxin. All are polypeptides of Mr about 150 kDa that have similar structure and pharmacological action. In their most active forms the toxins exist as dichain molecules in which a heavy (H) chain is linked by disulphide bonding to a light (L) chain. The H chain is believed to be associated with the highly specific and avid binding of toxin to the motor nerve end plates and also with the process of internalisation of the toxin. The toxic activity appears to be associated with the L chain which blockades the calcium-mediated release of acetylcholine, probably by interfering at the molecular level with the mechanisms whereby neurotransmitter-containing vesicles merge with the plasmalemma. The type A toxin is now used therapeutically to treat a variety of conditions involving involuntary muscle spasm. The therapeutic toxin is a neurotoxin-haemagglutinin complex isolated from cultures of C. botulinum. A controlled manufacturing process has been developed for the therapeutic toxin which is specially formulated to give a freeze-dried product having good stability.

Characterization of neurotoxigenic Clostridium butyricum strain by DNA hybridization test and by in vivo and in vitro germination tests of spores

The germination of spores of a neurotoxigenic Clostridium butyricum strain (BL 6340), which was isolated from infant botulism in Italy, and that of a nontoxigenic C. butyricum type strain (NCIB 7423) were studied. The spores of BL 6340 strain were killed at 80 C for 10 min, and required the mixture of L-alanine, L-lactate, glucose and bicarbonate for their optimal germination. These characteristics are the same as those of Clostridium botulinum type E strain, but different from those of NCIB 7423 strain. In a hybridization test, however, the labeled DNAs extracted from NCIB 7423 strain highly (98%) hybridized to the DNAs of the BL 6340 strain, but little (45%) to the DNAs of C. botulinum type E strain. The biochemical properties of the BL 6340 and NCIB 7423 strains were identical, but different from those of C. botulinum type E. These data confirmed that the BL 6340 strain belongs to C. butyricum species, but that only its characteristics of toxin production, its minimum requirements for germination, and the behavior of its spores to heat treatment are the same as those of C. botulinum type E. When conventionally raised suckling mice were injected with 5 x 10(7) spores of BL 6340 strain intra- or orogastrically, botulism was not observed. However, 8- to 13-day-old mice had type E botulinum toxin in the large intestine 3 days after introduction of its spores.

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.

Distinction between Clostridium botulinum type A strains associated with food-borne botulism and those with infant botulism in Japan in intraintestinal toxin production in infant mice and some other properties

Two strains of Clostridium botulinum type A associated with food-borne botulism and six strains associated with infant botulism in Japan were compared in intraintestinal toxin production in infant mice, in vitro toxin and hemagglutinin production, molecular sizes of the toxins, and some other properties. The infant botulism-associated strains, producing M toxin (Mr 300 kDa) but no hemagglutinin, showed significantly lower 50% infective doses in infant mouse intestines. The antigenicities of the toxin differed between the two groups, while the biochemical properties of the cultures did not. Besides infant botulism-associated strains, this set of properties were found only in a strain isolated from honey of South American origin.

[Botulism in cattle and meat inspection]

Three animals suspected of the presence of botulism, which were found to be infected with Clostridium botulinum type D were slaughtered in a special slaughter-house. The presence of C. botulinum in cattle and the decision reached by the meat inspection are discussed. Central registration of all cases of botulism observed in The Netherlands is advocated.

Distinct characters of Clostridium botulinum type A strains and their toxin associated with infant botulism in Japan

Four strains of Clostridium botulinum type A having been associated with infant botulism in Japan, and another strain isolated from honey not associated with infant botulism, were found to be hemagglutinin (HA) negative. These strains do not produce L (Mr 500 kDa) nor LL toxin (Mr 900 kDa) but M toxin (Mr 300 kDa) only. No marked difference was found between the HA-positive and HA-negative strains in other biochemical properties, but the HA-negative strains tended to colonize more easily in the intestines of infant mice than did HA-positive strains. The toxin of HA-positive strains and that of HA-negative strains differed in the antigenicity of part of the toxic component and that of the nontoxic component, and in the molecular size of the toxic component.

Comparative studies on Clostridium botulinum type A strains associated with infant botulism in Japan and in California, USA

Twenty strains of Clostridium botulinum type A associated with infant botulism cases, six in Japan and 14 in California, USA, were compared in their characters. All six Japanese strains produced medium-sized progenitor toxin (M toxin; Mr 300 k) but no hemagglutinin and showed lower 50% infective doses (ID50) in the infant mouse test; whereas most American strains produced large-sized progenitor toxin (L + LL toxins; Mr 500 k and 900 k) and hemagglutinin in addition to M toxin and showed higher ID50 in infant mice. No marked difference in the biochemical properties was found between the two groups except for two American strains.

Infantile botulism

A 4 month old boy presented with respiratory difficulty and hypotonia. Clostridium botulinum and its toxin were isolated from his faeces and he had electromyographic changes typical of infantile botulism. This is only the second case in the United Kingdom: unfamiliarity with the presentation could result in misdiagnosis.

[Type D and A Clostridium botulinum in necropsy samples from bovines with "mal de Aguapey"]

Bacteriological studies were carried out on several necropsy samples from five animals whose deaths had been attributed to bovine botulism. This disease, regionally called Mal de Aguapey, enzootically affects animals from a wide area of the north-east of Argentina (Province of Corrientes) with a bovine population estimated at near to 2,500,000. Either C. botulinum type D, its toxin or both were identified in all animal samples, alternatively in contents of rumen, jejunum, ileum, caecum and in samples of spleen, liver and kidney (Table 1). C. botulinum type A was isolated respectively from the liver and the kidney of two animals. Cultures of 100 soil samples taken in the enzootic area were positive only for C. botulinum type A (3%). These results enlarge and confirm previous findings and lend support to the botulinic etiology of the Mal de Aguapey.

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.

Quantification of Clostridium botulinum type A toxin and organisms in the feces of a case of infant botulism and examination of other related specimens

Bacteriological examinations were performed on the first case of infant botulism in Japan (an infant boy aged 79 days at onset of illness). Clostridium botulinum type A toxin and organisms were detected continually in the stools of the infant for at least 31 days and 39 days, respectively. The highest levels of the toxin and of the population of the organisms, 7.8 X 10(4) LD50/g and 1.3 X 10(6) colony forming units (cfu)/g, were detected in the stool specimen taken on the 20th day of illness. Type A organisms were detected also in the honey fed to the infant before onset of illness, teats of his feeding bottle, soil specimens taken at the house entry and the vacuum-cleaner dust. Fecal excretion of the toxin and organisms was no longer detected from the 68th day of illness and he recovered.

Infant botulism. Three cases in a small town

Through Dec 31, 1985, there have been six cases of infant botulism reported in Colorado. Three of these infants have lived in the same town of 800 people in western Colorado. Two of these three infants developed infant botulism within a six-month period in late 1981. The infants lived approximately 400 m apart; they had used the same crib at the time each developed botulism. A specimen from the crib yielded Clostridium botulinum, as did four soil samples from the town and house-dust samples from the home of a relative of the second infant. The third infant developed infant botulism in September 1984. This infant had not shared the crib. In this case, all seven samples of soil from various locations in the town yielded C botulinum, as did a sample of house dust from the home of this infant. The occurrence of these three cases in such a small town seems unlikely to be only coincidental. Investigations and reports of other such clusters may provide insight into modes of transmission of infant botulism.

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.

Two fatal cases of type E adult food-borne botulism with early symptoms and terminal neurologic signs

Type E botulism, one of the least common forms of botulinal intoxication on the East Coast of the United States, is described for two elderly patients with chronic underlying disease. Both patients consumed tainted kapchunka, a salted, ungutted whitefish. Gastrointestinal symptoms and signs were prominent, but neurologic complaints, although noted soon after the consumption of the fish in one patient, did not progress until late in the course of the patient's illness. One patient exhibited both urinary retention, which was reported mainly in one outbreak of type E botulism (M.G. Koenig, A. Spickard, M.A. Cardella, and D.E. Rogers, Medicine [Baltimore] 43:517-545, 1964), and muscular fasciculations, which have been rarely reported.

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.

Kinetics of growth and toxigenicity of Clostridium botulinum in experimental wound botulism

An animal model of wound botulism was developed in mice using an inoculum of Clostridium botulinum type A spores. The number of C. botulinum in infected wounds was quantitated by culturing on egg yolk agar, and the level of C. botulinum toxin in infected wound tissue was measured by a bioassay in mice and by an enzyme-linked immunosorbent assay. All infected mice receiving no further treatment developed neuroparalytic symptoms consistent with botulism after an incubation period of ca. 48 h, and all of these animals died. Serotherapy with C. botulinum type A antitoxin initiated 24 h postchallenge reduced the mortality rate to 5%. Treatment with metronidazole 2 to 24 h postchallenge resulted in recovery rates of 40 to 91%.

Improved selective medium for the isolation of lipase-positive Clostridium botulinum from feces of human infants

Isolation of lipase-positive Clostridium botulinum from fecal specimens establishes the diagnosis of infant botulism, contributes to the diagnosis of food-borne botulism, and is most easily accomplished by use of selective media. Modification of an available selective medium, C. botulinum inhibitory medium (CBI), enabled more rapid isolation of C. botulinum. The modified medium (botulinum selective medium [BSM] contained (per liter) 25 g of dehydrated heart infusion broth, 20 g of agar, 30 ml of egg yolk suspension, 250 mg of cycloserine, 76 mg of sulfamethoxazole, 4 mg of trimethoprim, and 100 IU of thymidine phosphorylase at pH 7.4. The two media were compared by using 15 fresh fecal specimens from infant botulism patients (10 type A and 5 type B) and a C. botulinum isolate that had been obtained from an infant botulism patient and that was mixed into a fresh stool specimen from a healthy human infant. In comparison to CBI, BSM always provided better suppression of the nonbotulinum fecal flora and earlier emergence of lipase-positive colonies. Diagnosis of infant botulism was accomplished sooner with BSM than with CBI because isolation of lipase-positive C. botulinum was easier.

Clinical, laboratory, and environmental features of infant botulism in Southeastern Pennsylvania

Forty-four cases of botulism occurred in infants in Southeastern Pennsylvania between 1976 and 1983. Forty-three were caused by Clostridium botulinum type B. Progressive weakness necessitated ventilatory support in 39 infants. Complications during hospitalization included otitis media in 13 patients and aspiration pneumonia in 11. Eight infants developed the syndrome of inappropriate secretion of antidiuretic hormone and two developed adult respiratory distress syndrome. One infant died of progressive bradycardia despite adequate control of ventilation. Manifestations of autonomic nervous system dysfunction recognized on admission to the hospital were constipation, distention of the urinary bladder, and decreased salivation and tearing. During hospitalization, some infants had unexpected fluctuations of skin color, blood pressure, and heart rate. Infants' strength improved despite persistent intestinal elaboration of toxin. C botulinum was isolated from seven of nine home or work environments sampled. All 44 infants were white and were receiving breast milk at the time of onset of symptoms. The majority had first feedings of nonhuman food substances within 4 weeks prior to onset of symptoms. Delineation of fecal flora in seven infants revealed predominance of enterobacteriaceae. Perturbations of intestinal flora during infancy, especially at weaning, may cause transient permissiveness to colonization by C botulinum.

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.

Continuous microbiological and pathological study of 70 sudden and unexpected infant deaths: toxigenic intestinal clostridium botulinum infection in 9 cases of sudden infant death syndrome

As part of a programme to exclude infection as the cause of death in infants who died suddenly and unexpectedly necropsies were carried out on 70 such infants. In 11 cases (15%), a pathological diagnosis could be made at necropsy; in 9 of these, causative bacteria or viruses were found. The 59 cases in which the cause of death could not be found had histological features characteristic of sudden infant death syndrome (SIDS). Botulinum toxin was found in 9 SIDS cases (15%). 8 of these infants had botulinum toxin and organisms of different types (A, B, C, F, G) in the contents of the ileojejunum or colon. 4 of them also had toxin in the serum. No botulinum toxin or organisms were found in the 11 infants who died of identified causes or 18 other infants who died in hospital of known causes.

Botulism intoxication after surgery in the gut

Botulism intoxication is described in a 45-year-old woman who was hospitalized with symptoms suggesting an intestinal obstruction. At intervention a 20-cm length of necrotic small intestine was excised and prophylactic antibiotics were given. Five days after surgery--during which time the patient was fed only parenterally--dryness of the mouth, difficulty in swallowing, general weakness, and difficulty with speech and in keeping her eyes open were noted. The patient was alert and well oriented. The clinical symptoms and the electrophysiological studies suggested the diagnosis of botulism. A serum sample caused death in mice upon inoculation and two samples of feces were positive for the presence of Clostridium botulinum organisms. Supportive treatment with botulinum antitoxin was given and the patient was discharged in good condition.

Botulism in metronidazole- treated conventional adult mice challenged orogastrically with spores of Clostridium botulinum type A or B

Conventional adult mice were pretreated with metronidazole to make their intestinal tracts receptive to colonization by Clostridium botulinum. These mice, in groups of 10, were fed 0 (controls), 10(2), 10(3), 10(4), or 10(5) C. botulinum type B spores and were placed for observation in filter-lid cages whose screen floors minimized the amounts of feces available for coprophagy. The opportunity to eat feces was made equal for all mouse groups by placing one mouse of every group in each of 10 cages. Mice given a spore inoculum began to develop botulism after incubation periods of slightly less than 2.75 days. Morbidity rates, which reached maxima within 5 days of challenge, were related to inocula levels. Mortality rates were also dose related. Mice given 10(5) spores and then type B antitoxin intraperitoneally, a treatment not affecting intraintestinal toxin production, remained healthy. Morbidity among control mice was seldom more than 10% and could be ascribed to toxin ingested with feces. A C. botulinum type A spore suspension gave similar results, although morbidity and mortality rates were generally lower than after challenge with a comparable number of type B spores. Mice challenged with 10(2) or 10(5) spores had similar toxin levels in their large intestines 48 h later. Morbidity rates correlated better with toxin levels in the small intestines.

Botulism and tetanus: selected epidemiologic and microbiologic aspects

Botulism is rare in both developing and developed countries. During 1980 only 89 cases (18 food borne, 68 infant, 2 wound, 1 unspecified) were reported in the United States. Coproexamination is essential for laboratory confirmation of infant botulism. Botulinal antitoxins of equine origin are used for treating food-borne and wound botulism but are usually not recommended for infant cases. Tetanus is much more common in some developing countries than in developed countries. During 1980 only 95 cases of tetanus were reported in the United States; in 68 (72%) of these cases, the patient was 50 years or older, and in only two (2.1%) cases was the patient younger than one year. Tetanus neonatorum is a major problem in some developing countries. Diagnosis of tetanus is based primarily on clinical findings, but laboratory studies can be helpful, especially in epidemiologic investigations. Human hyperimmune immunoglobulin is now used in the treatment of tetanus.

Type C botulism in young dogs

A diffuse lower motor neurone paralysis developed in a 6-month-old male Australian cattle dog pup 4 days after it had eaten the carcase of a rotting duck in Centennial Park, Sydney. Two other dogs which ate smaller portions of the same carcase were less severely affected. Clostridium botulinum type C was isolated from and C. botulinum type C toxin was detected in faeces from the severely affected dog. The serum contained 25 LD50 of toxin/ml. The high C. botulinum count and toxin level in the faeces declined progressively during the ensuing weeks, but 114 days after ingesting the carcase C. botulinum type C was still present in faeces and a low toxin titre persisted. Soil, mud and water samples in the area of the duck ponds in the park contained C. botulinum type C spores. Spores and high toxin titres were also found in the intestine of the carcases of 2 birds in the area.