Sensitivity to antibacterial drugs of biofilms formed by strains of vibrio cholerae of various serogroups.

Abstract

The ability of Vibrio cholerae to form biofilms may cause ineffectiveness of cholera treatment and prevention. The aim of the study was to determine the antibiotic sensitivity of V.cholerae in biofilms. Material and methods. Sensitivity to 11 antibacterial agents was determined for biofilms of 10 strains of V.cholerae of different serogroups isolated from humans and from water obtained for 48 hours at 37°C on plastic plates in vials with autoclaved tap water infected with a suspension of 104 V.cholerae microbial cells. For this purpose the plates were washed three times in physiological solution and transferred into penicillin vials with double dilutions of antibacterial agents in liquid nutrient medium (Martin's broth, pH 7.7). After 24 hours of cultivation in the thermostat (37°C), the biofilms were imprinted and 0.1 ml of plankton culture was seeded onto plates with Marten's agar (pH 7.7). After 24 hours in the thermostat (37°C), the biofilms were imprinted and 0.1 ml of plankton culture was sown on plates with Marten's agar (pH 7.7). The result was counted after 24 h, determining the minimum suppressive concentrations of preparations by the presence or absence of V.cholerae growth. Results. The strains studied in biofilm communities, in contrast to the planktonic form, were highly resistant to all antibacterial drugs taken in the study, except for ciprofloxacin and ceftazidime. To improve the effectiveness of treatment of cholera and other infections whose causative agents are cholera vibrio, it is necessary to determine the antibiotic sensitivity of V.cholerae biofilms.