Occurrence and Characteristics of CS31A Antigen‐Producing Escherichia coli in Calves with Diarrhoea and Septicaemia in Argentina

Abstract

CS31A is a K88-related non-fimbrial adhesin first described on Escherichia coli strains isolated from diarrhoeic and septicaemic calves. In this report, CS31A antigen was screened by immunological methods and confirmed by PCR among bovine E. coli isolates. In addition, CS31A-producing strains were characterized with respect to different fimbrial antigens, O-serogroup and other properties related to virulence. Faecal or tissue specimens of 100 diarrhoeic or septicaemic calves and 27 older cattle with different pathologies from 71 outbreaks or individual cases that occurred in Buenos Aires province, Argentina, were examined. CS31A + E. coli strains were isolated from 21 (21.0%) calves from 16 outbreaks or individual cases. No CS31A + E. coli was detected in samples from cattle more than 1 year old. Fimbriae F5, F41, F17a and F17b were not detected among the CS31A-producing strains. Three (14.3%) of the CS31A+ E. coli strains expressed the F17c fimbria. All of the 21 isolates exhibited at least one property of septicaemic strains (resistance to serum, production of aerobactin or colicins) but none of them demonstrated heat-stable enterotoxigenic activity. CS31A + E. coli isolates belonged to 10 serogroups, more commonly O8, O7, O17 and O21. The results obtained here confirm the worldwide distribution of CS31A antigen in bovine E. coli strains. However, CS31A + or CS31A + /F17c + E. coli were less frequently isolated than they were in North hemisphere countries.

Prevalence of Escherichia coli adhesion-related genes in neonatal calf diarrhea in Uruguay

“…Prevalences of CS31A (17.5%) and F17 (31.2%) genes were in accordance with those from previous reports in France, New Zealand, Iran, and in countries of the region such as Argentina and Brazil, but the F5 gene was less prevalent (< 1%) in the present study [17,[28][29][30][31]. These results are in accordance with a study by Kolenda et al, who reported a significant F5 prevalence reduction over the last decades [28].…”

“…However, only a small proportion of F17+ strains were also CS31A+, a lower prevalence compared to that in other studies [17,28]. Moreover, we revealed that f17A and f17G(II) were present together in a high proportion of the isolates compared to f17A and f17G(I).…”

“…F5 and F17 fimbriae and CS31A adhesin are among the most relevant adhesins in E. coli infections in calves, lambs, pigs and dogs, and are essential in the first colonization stages [8,14,17,26]. Additionally, recent studies have demonstrated that F17 and F5 together with F41 are significantly associated with calf diarrhea [27].…”

“…The CS31A antigen was first recognized as a capsule-like surface protein around the bacteria [15], and it has been extensively studied in septicemic and enterotoxigenic E. coli strains [15][16][17][18]. CS31A is usually expressed with other fimbrial antigens [16,19].…”

Leucine-Responsive Regulatory Protein Lrp and PapI Homologues Influence Phase Variation of CS31A Fimbriae

“…It is a capsule-like surface protein, immunologically related to F4 (K88) and F41 fimbriae (8). Experimental infections (9) and epidemiological data (10) suggest a close association of CS31A-producing strains with cases of septicemia (11). Pap-related fimbriae are the most frequent E. coli adhesins associated with human urinary tract infection, but they are also found in strains producing CS31A (12).…”