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N H Duncan

Publications and source records attributed to N H Duncan.

3 recordsLinked to original sources

Preparation of typing antisera specific for O antigens of Pseudomonas aeruginosa.

Results of serotyping 966 clinical isolates of Pseudomonas aeruginosa showed that 72% agglutinated specifically in one or another of the 16 typing antisera, but 28% agglutinated in two or more and often in as many as 10 antisera; this polyagglutinability correlated with a high incidence of cross-reactivity among the antisera. Absorption of each typing antiserum with either cell suspensions of five O-type strains or with a suspension of a particular polyagglutinable strain (SMC 247) abolished cross-reactivity in the typing antisera without significantly reducing titers against the homologous strains. All but four of the polyagglutinable strains agglutinated specifically in one or another absorbed antisera. The cross-reactions of unabsorbed antisera were interpreted to have been caused by antibodies directed not against specific O antigens but against thermostable specificities that remain undefined.

Absorption↗

Serratia marcescens-a marker for an infection control program.

An infection control program was instituted at The Victoria General Hospital, an 800-bed acute care hospital, in July 1977. Serratia marcescens had infected or colonized (I/c) 225 to 232 patients yearly for each of the three previous years. Since this organism is usually acquired nosocomially, we decided to use Serratia I/C as a marker for our infection control program. During the years 1977 to 1980, we identified and eliminated several reservoirs of Serratia (contaminated urine measuring containers, urometers, diabetic urine testing equipment and in-use contamination of 2% Hibitane). Readmission of previously I/C patients proved to be an increasingly important reservoir. During 1980, only 120 patients were I/C, and gentamicin-resistant isolates of S.marcescens had dropped from 44% in 1977 to 4.4% in 1980. Use of Serratia as a marker enabled us to monitor the efficacy of our infection control program and allowed us to prove to our health care workers the usefulness of many of the measures we introduced.

Adolescent↗