title: Serological characterization and antimicrobial susceptibility of Streptococcus suis isolates from diagnostic samples in Denmark during 1995 and 1996.
abstract: At the Danish Veterinary Laboratory Streptococcus suis infections in pigs were diagnosed in 114 cases in 1995 and in 151 cases in 1996. Isolates were serotyped using specific antisera against type 1 through 28 and a total of 67 cases from 1995 and 113 cases in 1996 were tested for resistance to 11 antimicrobial agents. The majority of cases were lung diseases (57%), followed by septicaemia (16%), meningitis (15%) and endocarditis (8%). Almost 96% of the isolates could be typed using the 28 antisera. The most common serotype was serotype 2 (29%), followed by serotype 7 (17%), and serotypes 3, 4 and 8 (9-10%). The remaining serotypes were observed in frequencies of less than 5%. Serotype 7 was more commonly isolated from septicaemia than the other serotypes. Serotype 2 was more commonly isolated from pigs older than 4 weeks compared to the other serotypes. Most isolates were susceptible to amoxycillin + clavulanate, ampicillin, ceftiofur, enrofloxacin, penicillin, spectinomycin, tiamulin and trimethoprim + sulphadiazine. A high frequency (> 30%) of resistance to tetracycline was observed. Among isolates of serotype 2, 9.7% were resistant to lincomycin and 12.9% to spiramycin. Among other serotypes 56.8% were resistant to lincomycin and spiramycin. The differences in susceptibility between isolates of serotype 2 and the other serotypes were statistically significant. Compared to a previous Danish study the distribution of serotypes of S. suis causing infections among pigs in Denmark has changed during the last 15 years.
authors.affiliation: Danish Veterinary Laboratory, Copenhagen, Denmark. faa@svs.dk
authors.forename: F M
authors.initials: FM
authors.lastname: Aarestrup
authors.forename: S E
authors.initials: SE
authors.lastname: Jorsal
authors.forename: N E
authors.initials: NE
authors.lastname: Jensen
mesh_terms: D000367:Age Factors; D000818:Animals; D000831:Animals, Newborn; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D003718:Denmark; D015994:Incidence; D008826:Microbial Sensitivity Tests; D012703:Serotyping; D013290:Streptococcal Infections / Q000175:diagnosis / Q000453:epidemiology / Q000662:veterinary*; D017011:Streptococcus suis / Q000145:classification* / Q000187:drug effects / Q000302:isolation & purification; D013552:Swine; D013553:Swine Diseases
chemical_list: D000900:Anti-Bacterial Agents