R Factors in Strains of Salmonella typhi and Shigella dysenteriae 1 Isolated During Epidemics in Mexico: Classification by Compatibility

Abstract

All 17 Salmonella typhi strains tested from the epidemic in Mexico carried R factors of compatibility group H, conferring resistance to chloramphenicol, streptomycin, tetracycline, and sulfonamides. Some S. typhi strains carried, in addition, non-conjugative, ampicillin resistance plasmids and R factors of the I or A-C complex. All 20 Shigella dysenteriae 1 strains tested of epidemic origin carried 0-group R factors. Ampicillin resistance in S. dysenteriae 1 was not proved to be plasmid borne. R factors of group H were not identified in any of the tested Mexican isolates other than S. typhi, but R factors of group 0 were identified in Escherichia coli, Shigella flexneri, and one strain of S. typhi, as well as in the epidemic S. dysenteriae. An R factor was identified which seemed to have two compatibility specificities, groups Iw and 0.

R plasmids conferring multiple drug resistance from shigella isolated in Korea

“…The incompatibility group B plasmids in shigella predominate in Central America, including Mexico, and in the United Kingdom (Datta & Olarte, 1974;Frost & Rowe, 1983), but we identified only two of Inc B having markers of Cm, Tc, Sm and Su, suggesting that this plasmid is rare in Korea. Incompatibility group FlI and related groups are common in Asia, Africa, and other parts of the world (Yoshikawa, Nagashima & Mitsuhashi, 1971;Watson, 1967;Frost & Rowe, 1983).…”

“…The incompatibility was tested by colony test (Datta & Olarte, 1974;Uhlin & Nordstroem, 1975). A list of standard R plasmids used was shown in Table 1.…”

“…The common group of R plasmids carried by shigella isolated in Mexico, U.S.A., Central America and the United Kingdom was Inc B (Datta & Olarte, 1974;Frost & Rowe, 1983). On the other hand, both in Japan (Yoshikawa, Nagashima & Mitsuhashi, 1971) and South Africa (Watson, 1967), F-like R plasmids predominate.…”

Shigellaspecies from Addis Ababa: frequency of isolation andin vitrodrug sensitivity

“…dysenteriae type 1 pandemic strain of Central America (Mata et al 1970) and Mexico (Datta & Olarte, 1974), i.e. resistance to chloramphenicol, tetracycline, streptomycin and sulphadiazine, was also found among our strains of Sh.…”

La fièvre typhoïde n’est plus aussi simple à soigner

“…La résistance à ces trois antibiotiques était portée par un plasmide de type I ncF (typage par la méthode d'incompatibilité), probablement acquis à partir de bactéries commensales du tube digestif, comme Escherichia coli. Les premières épidémies de fièvre typhoïde causées par des souches multirésistantes (au chloramphénicol, à la streptomycine, aux sulfamides et aux tétracyclines ou type « CSSuTe ») eurent lieu au Mexique et en Inde au cours de l'année 1972 [4,6,7]. L'épidémie mexicaine était de grande importance avec plus de 10 000 cas documentés.…”