The Investigation of Hospital Staphylococcus Outbreaks by Phage Typing

Timbury, Morag C (1959) The Investigation of Hospital Staphylococcus Outbreaks by Phage Typing. MD thesis, University of Glasgow.

Abstract

1. The method of phage typing Staphylococcus aureus has been described in detail together with some of the difficulties which are encountered in the setting up of a phage typing laboratory. 2. Differences in the percentage frequency distribution of phage types isolated from infections in surgical and general wards, in maternity units, and in outpatients are discussed. 3. Phage typing was used to investigate in some detail the epidemiology of outbreaks of staphylococcal infection in 3 surgical units and in a maternity hospital. 4. In the surgical units, most cases of wound infection had been acquired in the operating theatre, but in one outbreak there was some evidence that contamination with staphylococci in the wards prior to operation was probably responsible for a number of these. 5. The development of outbreaks of infection was found to be determined either by the infectivity of the infecting organism, by the wounds being exposed to an unusually dangerous source of organisms in which their natural infectivity is increased, or by the organisms having access to the wounds by a particularly dangerous route of inoculation. 6. Type 80 is a staphylococcal strain of exceptional infectivity. It showed a marked tendency to establish itself rapidly as a predominant cause of widespread infections. In one outbreak it caused frequent septic lesions other than wound infections. It did not cause unusually severe infections in the surgical units. 7. Active lesions were the most dangerous sources of staphylococci, and there was evidence that organisms derived from them were more infective than those from healthy carriers. The presence of infected patients in the wards was considered to have been an important factor in the spread of the epidemics. 8. Wounds are particularly susceptible to infection during operation and direct contact with organisms from a surgeon's hands is probably the most dangerous route of infection. 9. Most outbreaks of wound infection could be prevented if all those suffering from active lesions, whether patients or members of staff, were isolated from the operating theatre and wards. 10. In the epidemic in the maternity hospital, the main sources of infection were the infants themselves and the infection spread from infant to infant. 11. Newborn infants, particularly if they are ill or premature, are unusually susceptible to staphylococcal infection, but the epidemic was primarily determined not by this, but by the appearance of the highly infective type 80 among them. 12. Type 80 in the maternity hospital showed a marked ability to cause severe and sometimes fatal disease and to spread rapidly as the predominant infecting strain. The high case incidence of severe disease was probably due to the greater susceptibility of neonatal infants to staphylococcal infection as compared to adults. It had low powers of colonisation --- in the noses of the nurses and in the hospital environment generally. 13. A considerable amount of infection due to staphylococci acquired in the maternity hospital was discovered only after the infants had been discharged home. 14. Conditions in most maternity hospitals, where babies are congregated into small nurseries or open wards, are held to be largely responsible for the high incidence of staphylococcal disease there and for the appearance of outbreaks of of infection from time to time. 15. The spread of staphylococci from infant to infant and the consequent danger of the outbreak of serious infection could probably be prevented if babies were nursed beside their mothers in separate rooms. 16. Hospital staphylococcal outbreaks could be prevented by using the methods by which we successfully control other infectious diseases.

• Item Type: Thesis (MD)
• Qualification Level: Doctoral
• Keywords: Medicine, Epidemiology, Pathology
• Date of Award: 1959
• Depositing User: Enlighten Team
• Unique ID: glathesis:1959-79319
• Copyright: Copyright of this thesis is held by the author.
• Date Deposited: 05 Mar 2020 10:45
• Last Modified: 05 Mar 2020 10:45
• URI: https://theses.gla.ac.uk/id/eprint/79319