Outbreak Of Neonatal Diarrhea Research Articles

Epidemiologic approaches used in a herd health practice to investigate neonatal calf mortality

Epidemiologic methods were applied in an investigation into causes of neonatal mortality on a 1400-cow dairy in the southern San Joaquin Valley of California. A format for collation of information on birthdate and date of death was assembled into a matrix which improved conceptualization of the data and which simplified procedures for estimation of mortality rates. Contemporary and birth cohort life table methods, mortality density estimations and relative risk assessment were used to ascertain if there were high-risk groups of calves that could be identified by age, day-of-the-week born, day-of-the-week died and sex. During the outbreak of neonatal diarrhea on this dairy, female calves were found to have experienced an atypically higher rate of mortality (10.7%) than did males (5.3%). Calves of both sexes died between the ages of 9 and 19 days. In addition, the risk of dying was 11 times greater for calves born on Wednesdays than for those born on Saturdays. These findings formed the basis for recommended changes in management of neonatal calves on the dairy.

Emigration of polymorphonuclear leucocytes into the intestinal lumen of the neonatal piglet in response to challenge with K88-positive Escherichia coli

The emigration of neutrophils from the blood of neonatal piglets into the intestinal lumen in response to a K88-positive strain of Escherichia coli was investigated. The pig herd used was of known genetic susceptibility to K88-positive E coli and had recently experienced an outbreak of neonatal diarrhoea. Neutrophil emigration depended on certain factors. Neutrophils emigrated into ligated loops in susceptible piglets sucking immune colostrum from susceptible dams but not into loops in colostrum deprived resistant piglets or piglets sucking non-immune colostrum from resistant dams. In susceptible, colostrum deprived piglets neutrophils in intestinal contents were only associated with severe lesions. Large numbers of neutrophils which appeared at several foci on the villi were observed in three of six resistant piglets that sucked immune colostrum from susceptible dams. It was concluded that neutrophil emigration into the intestinal lumen of piglets could occur in response to K88-positive E coli and resulted not from the presence or absence of the intestinal K88-receptor but from the ingestion of immune colostrum.

Inhibition of adhesion of Escherichia coli K88 antigen by mammary secretions of susceptible and resistant sows

Anti-adhesive activities of colostrum and milk from genetically susceptible sows, which protected their susceptible offspring in an outbreak of neonatal diarrhoea caused by K88-positive Escherichia coli, were compared with the activities in mammary secretions of resistant dams that did not protect their susceptible progeny. There was significantly more anti-adhesive antibody in the secretions of susceptible sows than in resistant sows, both during the disease period, and 1 year later. Fractionation of colostrum by gel filtration and ion-exchange chromatography led to identification of the anti-adhesive antibodies as including both IgA and IgM.

Rapid diagnosis of rotavirus by an enzyme-linked immunosorbent assay (ELISA) in an outbreak of neonatal diarrhea in dairy calves

An outbreak of diarrhoea affected 13 of 20 calves in a herd of 260 cows and heifers. Faeces from 10 of the 13 calves were positive or doubtful for rotavirus group-specific (gs) antigens by ELISA. Faeces from 4 cows, including the dam of one affected calf, were all negative. Cell cultures of faeces from 3 affected calves were negative for rotavirus by immunofluorescence. Supernatant fluid from a culture of one calf was positive for gs antigens by ELISA. All 13 affected calves recovered after receiving antibiotics and colostrum. One calf, vaccinated against rotavirus at birth, had slight diarrhoea but recovered. ELISA is recommended for rapid diagnosis of rotavirus in calf diarrhoea.

Tyramine-producing streptococci in neonatal diarrhoea.

An outbreak of neonatal diarrhoea associated with large numbers of Streptococcus faecalis var. zymogenes is described.A follow-up survey showed that 23.3% of 347 healthy babies carried this organism without ill effect. The tyrosine decarboxylase activity of the streptococci from both sick and healthy babies was identically high. It is suggested that the tyramine-producing activity of these streptococci was not the primary cause of the diarrhoea.

Group D streptococci in the faeces of healthy infants and of infants with neonatal diarrhora

1. The aerobic faecal flora of healthy infants was found to comprise coliform organisms, streptococci and occasionally yeast and spore-bearing organisms. Coliforms and streptococci occurred more frequently in the stools of artificially fed than of breast-fed infants in whom micrococci occurred more frequently.2. Of 191 strains of streptococci isolated from healthy infants' faeces and tested serologically, 8·90% fell into Lancefield's group D. Of the stools examined 93·7% contained group D streptococci.3. A comparison of the group D streptococcal flora of the faeces of healthy infants and of infants associated with outbreaks of neonatal diarrhoea showed that the percentage of these organisms found in the latter was much higher than in healthy infants, the modes being 90–100 and 10–20% respectively.4. The same species and varieties of group D streptococci were found in both healthy and sick infants. Streptococcus faecalis was the predominant species.5. Serological typing of strains of group D streptococci from healthy infants from three maternity hospitals showed that particular types tended to predominate in each maternity unit and to recur over a considerable period of time, in each instance suggesting a reservoir of dissemination to successive infants as they arrived. With artificial feeding an increased diversity of serological types was found.6. Serological types of group D streptococci isolated from sick infants during ten outbreaks of neonatal diarrhoea showed a considèerable variety. Apart from one outbreak (A), where type I was isolated with great frequency, one or two types tended to predominate in each outbreak, but not to any great extent, and not always the same one.7. Types 1, 5, 8 and 9 were the types of group D streptococci most commonly found in both healthy and sick infants, but type 1 occurred in a significantly greater percentage of sick than of healthy infants.8. Tyrosine decarboxylase activities of group D streptococci were usually associated with serological types. The distribution of activities of these organisms was similar in healthy and sick infants.9. The possibility that neonatal diarrhoea may consist of more than one syndrome is discussed, and several of the outbreaks described here are classified into two groups.The author wishes to thank Dr A. T. R. Mattick for his constant interest in this work; Dr P. M. P. Shattock for advice and many valuable suggestions; Dr E. F. Gale for advice and material; Dr E. H. Gillespie, Dr A. M. McFarlan and Dr J. Wright for material and clinical data; Dr P. White and Miss Z. D. Hosking for assistance with the statistical computations; Mr L. G. Newland for technical assistance; and to express her appreciation to the Medical Research Council for a grant which enabled this work to be carried out.

The serological typing of group D streptococci associated with outbreaks of neonatal diarrhoea.

Summary: By the preparation of specific type sera 24 types of streptococci within group D are designated on the basis of agglutination tests. Subtypes associated with three of these types are indicated by reciprocal absorption. Precipitin tests with absorbed sera substantiate the division of types by agglutination. Of 353 strains of streptococci identified serologically as group D and further specified by physiological characters, 281 were typed by slide agglutination; the remaining 72 did not fall into any of the 24 types. Whilst there is no absolute correlation between serological type and physiological characteristics, a broad division can be made between Streptococcus faecalis and its varieties on the one hand and Strep. durans, Strep. bovis and various unclassified strains on the other.