Phage Typing Of Strains Research Articles

Biotypes, serotypes and phage types of caprine strains of Staphylococcus aureus

Nine of 11 caprine strains of Staphylococcus aureus examined belong to biotype C. They were typable serologically using antisera developed for typing human strains of Staphylococcus aureus. H2 was found to be the dominant thermostable antigen whilst 1 and 0 were the most common thermolabile antigens. Some strains possessed protein A and poly A beta (beta-glucosaminyl ribitol teichoic acid). Phage typing of the strains was achieved with an international set of phages for typing human strains of Staphylococcus aureus and they belong to phage groups II, and the mixed group.

Sources of staphylococcal wound sepsis in surgical patients

Sources of Staphylococcus aureus have been studied in 124 surgical patients of whom 20 (16%) developed wound sepsis. Staph. aureus was isolated from the gastro-intestinal tract only once, but 26 of 113 (23%) patients were found to be nasal carriers. Twenty-seven per cent of carriers developed infections whereas only 10% of non-carriers became infected. Phage typing of strains causing wound infections showed that they originated from multiple and mostly unidentified sources. Three of seven infections in nasal carriers were with organisms of the same phage type as those found in the nose. These results indicate that staphylococci of nasal origin are not the major source of infected surgical wounds.

A second focus of cholera El Tor in India.

Summary The first area to be involved in an outbreak of cholera El Tor in India was Calcutta where El Tor strains were indentified in April 1964. Another focus harboring this disease has recently come to light in the course of routine phage-typing of the causal strains isolated in cholera epidemics in Surat and Baroda in the State of Gujarat. The El Tor strains of Surat and Baroda were nonhemolytic and therefore indistinguishable by hemolytic test from the Vibrio cholerae strains isolated simultaneously. In the absence of phage-typing the V. el tor strains from Gujarat would have passed as classical cholera vibrios. The value of routine phage-typing of strains isolated in all fresh cholera outbreaks has thus been confirmed. By the use of chicken erythrocytes in place of sheep cells in the hemolysis test, all the apparently non-hemolytic V. el tor strains proved hemolytic. But the diagnostic value of the chicken-cell test is minimized because of the lysability of chicken erythrocytes by some classical cholera vibrios. The V. el tor strains from Gujarat differed in phage-sensitivity patterns from those isolated in the Calcutta area. Phage-typing of El Tor strains from all the future cholera El Tor outbreaks in India is likely to provide valuable information about the mode of spread in India of cholera in general and cholera El Tor in particular.