Fig. 1 The sketch of the neonatal intensive care unit in Tokyo Women's Medical College Hospital. (1979)

Key words: neonatal intensive care unit, bacterial contamination, Pseudomonas, Stophylococcus

Fig. 1 The sketch of the neonatal intensive care unit in Tokyo Women's Medical College Hospital. (1979)

Table 1 Estimation of aerial bacteria in neonatal intensive care unit. Petri dishes containing heart infusion agar medium (Eiken) were exposed to air for 30 and 60 min., and incubated at 37 Ž. for 24 hours.

Table 2. Isolation and identification of bacteria isolated from the neonatal intensive care unit. 1) Identified as Acinetobacter. 2) Identified as Staphylococcus aureus. 3) Brushes sterilized in the autoclave were used. 4) Examined after washing by disinfectant. 5) Baby-bath tubs sterilized in the autoclave were used for each baby. 6) Disinfectant used was 0.1% benzethonium chloride (hyamin) in 1973, and 0.02% chlorhexidine gluconate (hibitane) in 1979. Table 3 Isolation and identification of bacteria from the incubators and suckling tools in the neonatal intensive care unit. 1) Identified as Acinetobacter. 2) Identified as Staphylococcus aureus

Table 4 Isolation and identification of bacteria from the fingers of doctors, nurses and helpers working in the neonatal intensive care unit. Fingers were rubbed on the medium.

Table 5 Certain bacteria isolated from the throats of new born infants and nurses. Table 6 Senstitvity to antibiotics of the Staphylococcus aureus strains isolated. 1) Identified as Staphylococcus aureus. The sensitivity was determined by the single disc (Showa yakuhin kako Co.) on the Heart infusion agar medium (Eiken).

Table 7 Sensitivity to antibiotics of the Pseudomonas aeruginosa strains isolated. The sensitivity was determined by the single disc (Showa yakuhin kako Co.) on the heart infusion agar medium (Eiken).

3) Thom, A. R., Cole, A. P. and Watrasiewicz, K.: Pseudomonas aeruginosa infection in neonatal nursery, Possibly transmitted by a breast-milk pump. Lancet, I: 560-561, 1970. 11) Wilson, M. G., Nelson, R. C., Phillips, L. H. and Boak, R. A.: New source of Pseudomonas aeruginosa in a nursery. J. A. M. A., 175: 1146-1148, 1961. 12) Sever, J. L.: Possible role of humidifying equipment in spread of infections from the new born nursery, Pediatrics, 24: 50-55, 1959. 13) Edmondson, E. B., Reinarz, C. A., Pierce, A. K. and Sandford, J. P.: Nebulization equipment, a potential source of infection in gram-negative pneumoniae. Amer. J. Dis. Child., 111: 357

360, 1966. 14) Burdon, D.W. and Whitby, J.L.: Contamination of hospital disinfectants with pseudomonas. Brit. Med. J., 2: 153-154, 1967. Analytical Examination of Bacteria in a Neonatal Intensive Care Unit Morimasa YOSHIOKA*, Kiyo SUSHIDA*, Hisao NAKANO*, Masumi YAYOSHI*, Minako ARAAKE*, Takako ITO*, Masako KONO*, Mariko WAKAI*, Kazuko YOKOTA** and Kyoko URAMOTO** Departments of Microbiology* and Pediatrics**, Tokyo Women's Medical College, Tokyo Examinations of pathogenic Escherichia coli, Staphylococcus and Pseudomonas from various objects, new-born infants and workers in the neonatal intensive care unit in the college hospital were performed in 1973 and 1979. In 1978 new nursery which equipped the clean air ventilation and pre-room for incoming person was opened in the hospital ward newly constructed and had been used for 8 months until this study. The results obtained as follows: 1. Pathogenic Excherichia coli was not isolated from any specimen. 2. Staphylococcus aureus was isolated from sink and catheters for nutrition. The isolates showed resistance to penicillin, erythromycin, and sulfoisoxasol. Staphylococcus epidermidis was isolated from fingers of all of doctors and nurses working in nursery. 3. Pseudomonas aeruginosa was isolated from sink, catheters for nutrition and thermometer and humidifier of incubators in both examinations, and also from the throats of new-born infants in 1973 and from the throats of new-born infants and nurses in 1979. The isolates showed sensitivity to gentamicin. 4. The results suggest that new-born infants and medical care takers are capable both of recieving and of mediating microbial contaminations, and also new-born infants, nurses and spots retentive of moisture are easily contaminated by Pseudomonas aeruginosa.