Skin Flora of the Newborn

589 SKIN FLORA OF THE NEWBORN I. SARKANY tative as well as quantitative distribution of the normal flora must be accurately mapped out. Methods M.R.C.P. CONSULTANT DERMATOLOGIST CHRISTINE C. GAYLARDE B.Sc. Lpool ASSISTANT, DERMATOLOGY DEPARTMENT, HOSPITAL, GRAY’S INN ROAD, LONDON W.C.1 RESEARCH ROYAL FREE The bacterial flora of 33 babies at the moment of birth and 410 other newborn was babies studied, using a new contact-plate method. Although the skin of babies delivered by cæsarean section was sterile, the skin of the baby at normal delivery was colonised mainly by non-pathogenic staphylococci and diphtheroid bacilli. Occasionally coliforms and streptococci were present. The pattern of skin flora was essentially uninfluenced by routine careful manipulations, including washing of the baby and forceps delivery. This suggested the existence of a characteristic natural pattern of skin flora in the newborn. There was a relative dearth of diphtheroid bacilli at birth and following a rapid increase, there was a levelling out after two days. The number of staphylococci at birth was somewhat larger and they too reached a plateau after the second day. The study was concerned with the bacterial flora of the skin of the newborn from the moment of birth over the first six days of life. Summary The methods for sampling skin bacteria include swabbing, the use of contact plates, and stripping with adhesive tape. We developed a contact-plate method making use of a plastic cup with a diameter 1-5 cm. using caps from 10 ml. plain blood tubes (Staynes). This gave a standard sampling area of 1.76 sq. cm. For routine collections, horse-blood agar and Sabouraud’s medium were used. The plates were incubated aerobically at 37°C for 48 hours. Plates obtained from babies at the moment of birth and cultures from the birth canal after rupture of the membranes were also incubated anaerobically. Primary cultures were identified by colonial and cell morphology, and subcultures were made on MacConkey’s, tellurite, chocolate, and P.N.F. (polymyxin, neomycin, fucidin in bloodagar), as required. Gram-positive bacilli producing black colonies on tellurite agar were classified as Corynebacterium spp. (diphtheroid bacilli) but were not studied in more detail. Streptococci were identified by their growth on P.N.F. agar. No grouping of streptococci was carried out. Gram-negative bacilli capable of growth on MacConkey’s medium were Introduction WE have examined the bacterial skin flora of 33 babies at the moment of birth and of 410 babies investigated during the first six days of life. The normal flora of the skin of the newborn has not been previously investigated in detail (Hurst 1965) and we decided to follow the time course of the colonisation of the skin by microorganisms, both non-pathogens and pathogens. The findings during the first day of life will be published in detail elsewhere (Sarkany and Gaylarde 1967). The problem of enumerating and evaluating the bacterial flora of the skin has significance from various points of view. Clinically, it is helpful to know what pathogenic organisms can survive long enough on the skin to be passed from individual to individual. The normal flora must also be known, since under abnormal conditions the ecology of the skin surface can change rapidly and allow a previously minor, but potentially pathogenic, part of the flora to become predominant over the apparently harmless organisms usually found (Williamson 1965). The normal flora must also be known if the effect of various manipulations on the baby after birth is to be assessed. Finally, if selective recolonisation based on bacterial interference (Shinefield et al. 1965) is to be successfully used in the infant, the quali- Fig. 2-Diphtheroid bacilli on the skin of the newborn. Note small numbers at the moment of birth. L2 590 referred to as coliforms. These bacteria were further classified, in the early stages of the work, by sugar-fermentation tests. Staphylococci were examined routinely by the slide coagulase test. Although it was appreciated that the slide test detected only cell-bound coagulase and that free coagulase was produced by some slide-negative strains, tube tests were not done because of the very large numbers involved and the likelihood of missing only a very small percentage of Staphylococcus pyogenes with the slide test. Five standard sites were examined: the vertex of the head, scapular region, axilla, periumbilical area, and groin. All sites were examined immediately on presentation of the relevant part during delivery and subsequently at hourly intervals for seven hours, at two-hourly intervals for ten hours, four-hourly for two days, and daily for six days. Normal deliveries, forcepsassisted births, and babies delivered by csesarean section were studied separately. The flora of the birth canal was examined after rupture of the membranes. Swabs were also taken from skin of the newborn before and after washing of the baby with soap and water. Results Staphylococci and diphtheroid bacilli were the main types of organisms present on the skin of the newborn. In addition, about 10% had coliforms, mainly Escherichia coli and Proteus sp., and 4’5% were found to have streptococci. No yeasts and no lactobacilli were detected. All five sites studied had a moderately large number of coagulase-negative staphylococci when first examined. Between 3 and 10 colonies per plate were counted, the highest numbers being present in the axilla. After a transient slight fall in the numbers of this organism in most sites over the next nine hours, a sharp increase took place during the next sixteen hours, followed by a levelling out of the number of staphylococci after the second or third day and subsequently they remained essentially unchanged (fig. 1). In contrast, there were very few or no diphtheroids on the skin of the babies at birth in all five sites. Over the next twelve hours, there was a very sharp rise in the numbers of this organism, reaching levels of 10-20 colonies per plate. After a transient fall at twenty-four hours, the level of these organisms remained remarkably constant (fig. 2). B Of 5 babies delivered by caesarean section, 4 were completely sterile and the fifth had small numbers of coagulase-negative staphylococci. The subsequent pattern of colonisation of the skin of these babies by bacteria was exactly similar to that of the babies born normally. The flora of forceps-assisted deliveries was essentially that of the normal. Finally, washing of the baby with soap and water appeared not to influence the degree or pattern of normal skin colonisation. Vaginal swabs immediately before delivery-i.e., after rupture of the membranes-showed a slight predominance of coagulase-negative staphylococci over diphtheroids. No lactobacilli were isolated. Of 9 cases studied, only one culture yielded yeasts (Candida albicans). Comment Although the skin of babies delivered by caesarean section is sterile, the skin of the newborn at the moment of normal delivery is colonised by bacteria. As at all ages, non-pathogenic staphylococci and diphtheroids are the predominant organisms. These types of bacteria were also found in the birth canal immediately before delivery. There is, therefore, an apparent relationship of the flora of the vagina and the newborn skin and it seems that the birth canal is the main source of the bacteria. The absence of yeasts in the newborn is quite compatible with the low incidence of yeasts in the birth canal just before delivery. There may have been a relatively low number of yeasts on the newborn skin which were not detected because of the small areas sampled with our plastic cup. The absence of lactobacilli both on the newborn skin and in the vagina just before delivery is more difficult to understand. Aerobic and anaerobic culture on blood-agar should have detected this organism. It is known, however, that the cultural requirements of this species are at times exacting and more detailed investigations into this problem will be necessary. Normal manipulations of the newborn, washing and even forceps delivery, produced little or no change in the skin flora. This would suggest that there was a characteristic pattern in the normal colonisation of the newborn skin which remained uninfluenced by routine careful procedures. Staph. aureus was only rarely found and was cultured only twice from the 33 newborn. We thank Dr. Nuala Crowley for help and advice and Mr. B. Farrell for technical assistance. We are grateful to the consultant obstetricians and nursing staff for allowing us to study the babies and for a grant from the William Shepherd Bequest. Requests for reprints should be addressed to 1. S. REFERENCES Hurst, V. (1965) in Skin Bacteria and their Role in Infection (edited by H. I. Maibach and Gavin Hildick-Smith); p. 127. New York. Sarkany, I., Gaylarde, C. C. (1967) Unpublished. Shinefield, H. R., Ribble, J. C., Eichenwald, H. F., Boris, M., Sutherland, J. M. (1965) in Skin Bacteria and their Role in Infection (edited by H. I. Maibach and Gavin Hildick-Smith); p. 235. New York. Williamson, P. (1965) ibid. p. 3. SIMPLE GOITRE IN GLASGOW AND DUMFRIES SCHOOLCHILDREN W. R. GREIG I. T. BOYLE M.D. Aberd., M.R.C.P.E. M.B., B.Sc. Glasg., M.R.C.P., M.R.C.P.G. WBLLCOME RESEARCH FELLOW AND HONORARY LECTURER IN MEDICINE J. A. LHCTURER IN MEDICINE BOYLE J. A. THOMSON M.B. Glasg., M.R.C.P., M.R.C.P.E. LECTURER IN MEDICINE I. M. D. M.B. M.B. Glasg., M.R.C.P., M.R.C.P.G. SENIOR MEDICAL REGISTRAR T. H. A. HASSAN JACKSON Glasg., M.R.C.P., M.B. Cairo, M.R.C.P., M.R.C.P.E. M.R.C.P.E. MEDICAL REGISTRAR H. W. GRAY M.B. Glasg. SENIOR HOUSE-OFFICER E. M. MCGIRR M.D., B.Sc. Glasg., F.R.C.P., F.R.C.P.G., F.R.C.P.E. MUIRHEAD PROFESSOR OF MEDICINE From the University Department of Medicine and Department of Endocrinology, Royal Infirmary, Glasgow C.4 Summary A survey for the prevalence of goitre in Glasgow, Dumfries, and Nithsdale schoolchildren aged 5-15 years is described. In 4748 Glasgow children the goitre-rate was 13·3%, in 968 Dumfries children it was 15·6%, and in 486 Nithsdale children it was 29·6%. In both Glasgow and Dumfries the goitrerate was influenced by sex and age, high rates being found in female children aged 11-15 years. In contrast, in Nithsdale in both the younger (5-10 years) and in the older children (11-15 years) and in the females and males the goitre-rate was consistently high, varying only between 28·7% and 31·1%. It is concluded that whereas in Glasgow and Dumfries the chief cause of goitre is an