A pseudo-outbreak of salmonellosis.

during July 1991, a single laboratory reported an increased number of an unusual salmonella isolate. An outbreak control team was convened. A case was defined as an individual with diarrhoea from whose faecal sample Salmonella hadar was isolated after 1 July 1991. By 30 July, 90 isolates had been identified and 57 persons interviewed including 39 primary cases. Interviews failed to identify any common features among the cases. A review of the laboratory procedures revealed that the selenite enrichment medium was inoculated using the spoon from the stool collection kit after it was used to emulsify the faecal sample with saline for microscopy. Salmonella hadar was isolated from this saline. Once this practice was stopped, no further isolates of S. hadar were made. This pseudo-outbreak is a powerful reminder to verify the existence of an outbreak, especially when epidemiological data are inconsistent.     

Nutritional effects of salmonellosis in mice.

Mice infected with a standard challenge of Salmonella typhimurium manifest a number of changes associated with endotoxemia. These changes result in profound alterations in the nutritional and metabolic status of the host. Food and water intake approaches levels of total inanition, blood glucose declines more rapidly than in fasted controls, hepatic phosphoenolpyruvate carboxykinase (the enzyme that is rate limiting in gluconeogenesis) shows diminished activity and loss of cortisol inducibility, and hypothermia, rather than hyperthermia, becomes acute. These changes occur at a time when bacteremia is first demonstrable. This occurs on the 3rd day after infection under the conditions employed. Death occurs in most mice within the next 24 to 48 hr. Mice vaccinated with a highly immunogenic ribosomal preparation and subsequently infected with the standard number of organisms did not manifest the above changes. Other work from this laboratory has established that effects of the type described are elicited by bacterial endotoxin as a result of mediating substances released into the blood by cells of the reticuloendothelial system. Presumably these substances appear in blood of infected mice as well.     

Extraintestinal salmonellosis

Between 1969 and 1984, 6564 non-typhoid salmonella strains were isolated at the Liverpool Public Health Laboratory of which 194 (3.0%) were from extraintestinal sites. Blood (34%) and urine (32%) isolates accounted for two-thirds of these, with the remainder being recovered from pus and inflammatory tissue (23%), bone (5%), cerebrospinal fluid (5%) and sputum (3%). Certain serotypes tended to cause more invasive disease than others, i.e. Salmonella choleraesuis, S. dublin, S. london, S. virchow and S. panama: this association for S. london has not previously been described. The spectrum of disease caused by non-typhoid strains was broad. This survey confirms the importance of non-typhoid salmonellas as occasional causes of invasive disease and local sepsis outside the gastrointestinal tract.     

Human salmonellosis transmitted by a domestic turtle.

Salmonella typhimurium was isolated in the culture test of a small child admitted to hospital suffering from febrile gastroenteritis with stools containing traces of mucus and blood. Her mother also resulted positive for this microorganism. The family had recently bought a small turtle, imported from Florida, at the city fair. Further tests revealed Salmonella typhimurium in both the turtle's feces and the water in its tank.     

Diagnosis of salmonellosis

The determination of clonal identity of bacterial isolates of Salmonella, in particular epidemiological important serovars of Salmonella, is an unequivocal prerequisite for the study of the epidemic process of salmonellosis. This is demonstrated for the serovar S. typhimurium by means of classical as well as molecular methods for epidemiological subdifferentiation.     

Epizootiology of salmonellosis

During the period from 1980 to 1987 a decreasing trend of Salmonella isolations could be registered in animal production. With regard to Salmonella serotypes host adapted to domestic animals both main as subordinated series of infections are analyzed in epizootic actions. In all cases of not host adapted Salmonella serotypes vector specific contagious manners are dominating.     

A cost benefit study of milk-borne salmonellosis.

An estimate of the benefits which would result from a ban on the sale of non-pasteurized milk in Scotland has been assessed by costing a recent outbreak of milk-borne salmonellosis in the Grampian Region. The cost of such a ban would not exceed the benefits under any but the most severe assumptions about the values attached to intangible benefits.     

Epidemiology of salmonellosis

The diagnostically and in regard to surveillance rather comprehensively recorded salmonellosis bear the character of a model of zoonotic diarrhoeal diseases. Whereas those serovars predominantly adapted to human beings or animal species are without any importance in this connection, such serovars with own epizootic processes in different animal species with or without causing illness are able to be transferred to human beings via foods of animal origin and to act as etiological agents of gastroenteritis. Some strains of them equipped by special properties often encoded by plasmids can be transferred from man to man, too. In GDR in 1987 S. enteritidis (34.0%), S. typhimurium (17.9%), S. manhattan (7.7%) and S. agona (7.4%) amounted to two thirds of all the salmonella isolates in connection with human enteritis. For analyzing epizootic-epidemic processes in the case of rare serovars the identity of serovars is sufficient in first approximation, in the case of frequently isolated serovars the complex typing of the concerned strains by using epidemiological laboratory methods is required.     

Infant feeding practices and obesity.

Selected assumptions regarding associations between artificial feeding and infantile obesity are examined. Although some artificial baby foods (desserts, meats, egg yolks) have considerably greater caloric density than breast milk, a large class of baby foods and most milks and formulas are comparable to breast milk in caloric density. The intake of infant foods seems to be related more to caloric density than volume. Modern day artificial feeding in developed countries tends to produce larger weight gains than breast feeding, although no good data exist to evaluate the composition of these weight gains. Many more data from well planned studies are needed to fully elucidate possible mechanisms of infantile obesity.