Infant botulism in a breast-fed infant from rural New South Wales

Viable Clostridium botulinum spores not detected in the household dust of major Canadian cities

Clostridium botulinum causes infant botulism by colonising the intestines and producing botulinum neurotoxin in situ. Previous reports have linked infant botulism cases to C. botulinum spores in household dust, yet the baseline incidence of C. botulinum spores in residential households is currently unknown. Vacuum cleaner dust from 963 households in 13 major Canadian cities was tested for C. botulinum using a novel real-time PCR assay directed against all known subtypes of the botulinum neurotoxin gene. None of the samples tested positive for C. botulinum. Analysis of a random subset of samples by MALDI Biotyper revealed that the most common anaerobic bacterial isolates were of the genus Clostridium and the most common species recovered overall was Clostridium perfringens. Dust that was spiked with C. botulinum spores of each toxin type successfully produced positive real-time PCR reactions. These control experiments indicate that this is a viable method for the detection of C. botulinum spores in household dust. We make several recommendations for future work that may help discover a common environmental source of C. botulinum spores that could lead to effective preventative measures for this rare but deadly childhood disease.

Global occurrence of infant botulism, 1976-2006

OBJECTIVE

To summarize the worldwide occurrence of reported infant (intestinal toxemia) botulism cases since first recognition of the disease in 1976.

PATIENTS AND METHODS

We collected information on infant botulism cases by active and passive surveillance, by provision of therapeutic Human Botulism Immune Globulin to suspected cases, and by searching the medical literature. We defined a case as laboratory-confirmed botulism that occurred in an infant <or=12 months of age that was not caused by the ingestion of botulinum toxin in food.

RESULTS

Twenty-six countries representing 5 continents reported the occurrence of at least 1 case of infant botulism among their residents. The United States, Argentina, Australia, Canada, Italy, and Japan, in this order, reported the largest number of cases. A history of honey exposure was significantly more common among case subjects hospitalized outside of the United States than among those who were recently hospitalized in California.

CONCLUSIONS

Most countries have not yet reported cases of infant botulism. This limited reporting of the disease to date contrasts with the known global occurrence of Clostridium botulinum spores in soils and dust and suggests that infant botulism may be under-recognized, underreported, or both. When bulbar palsies, hypotonia, and weakness are present, physicians should consider the possibility of infant botulism even if the patient has not been fed honey. Publication of additional case reports and surveillance summaries will enhance understanding of the occurrence and extent of this under-recognized disease.

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 in New South Wales, 1980-1981

The isolation of Clostridium botulinum from the home environment of New South Wales patients with infant botulism is reported. Of the three cases of infant botulism type B, the bacteria were isolated from soil around the dwelling in one, and from tank rainwater in another. In one case with type A, the bacteria were present in the soil, vacuum-cleaner dust, and tank rainwater. The bacteria were not detected in the environment of two adult patients and a child with C. botulinum in their stools. The home location of the patients with infant botulism, and the frequency of isolation of the bacteria from rainwater, soil and vacuum-cleaner dust in Cobar, Nyngan, some Sydney suburbs, and at five pastoral homesteads suggest that infants in rural areas are more at risk than those in large metropolitan areas. The age of the infants with diagnosed botulism in New South Wales, compared with those reported in the United States data, strongly suggests that the disease is not being fully recognised in younger infants.