The incidence of penicillin-resistant staphylococci in a semi-closed community

Yearly incidence of penicillin-resistant staphylococci in man since 1942

For this study of the year-by-year change in the incidence of carriage of or infection by penicillin-resistant, coagulase-positive or haemolytic staphylococci in man, 248 contributions to the medical literature have been analysed and grouped under three main headings: people in hospitals, people with clinical signs attending out-patients' wards or doctors' surgeries, and people not currently receiving medical care.This analysis shows that there has been a steady increase in resistant strains among persons of the first group from 1942 to 1955, followed by a slight decrease to 1959, possibly owing to more discriminating use of penicillin. A steady increase was found in the other two groups from 1942 to 1959, the rate of increase being more pronounced among the group with clinical signs.The authors draw attention to the possible influence of the ingestion of penicillin with food on the incidence of resistant strains; the occurrence of such strains in certain foods; and the need for standardized techniques for sampling, for testing for staphylococci and for determining resistance.

Staphylococcal carriage in man. An attempt at a quantitative survey

The author reviews the published findings on the carriage of Staphylococcus pyogenes var. aureus during the last two decades, dealing mainly with observations made in British Commonwealth countries, Scandinavia and the USA. The importance of the role played by staphylococcal carriers in the spread of infection both in hospitals and among adults and children in the general population is clearly brought out and is of particular interest in view of the current increase in resistance of staphylococcal strains to antibiotics.There does not appear to have been any well-defined trend towards either an increase or a decrease in staphylococcal carriage in the past twenty years; annual variations have been quite considerable and the precipitate drop in the carriage rate in hospitals in 1949 (perhaps due to the extensive use of penicillin) has since been made up. A particularly high carriage rate was found among hospital staff and twice as high a rate among children born in hospitals as among those delivered at home.Closer study and better control of staphylococcal infections in hospital wards are clearly necessary. It is appreciated, however, that, before more effective control measures can be taken, there must be improvements in the present methods of sampling, in the testing of strains for pathogenicity and in other techniques.