Related Experiment Video
Updated: Jun 21, 2026

Laboratory Techniques Used to Maintain and Differentiate Biotypes of Vibrio cholerae Clinical and Environmental Isolates
Published on: May 30, 2017
[Features of biologic characteristics of Corynebacterium diphtheriae circulating in postepidemic period]
Aim:
To study main biologic characteristics of C. diphtheriae strains circulating in North-West Region of Russia for the last 15 years.
Materials And Methods:
Six hundred and fifty strains of C. diphtheriae isolated from ill persons and carriers in Saint-Petersburg, Leningrad region and Vologda region at various periods of time were studied. Identification of an infectious agent was performed according to methodic guidelines MU 4.2698-98. IHA-chromatographic test (ICS-test) on the basis of MKA, polymerase chain reaction, determination of adhesive activity and susceptibility to antibiotics were performed.
Results:
In recent years, circulation of C. diphtheriae strains with biologic characteristics similar to that observed in strains isolated during diphtheria epidemic and differed from that observed in strains isolated during the period of low incidence. Proportion of strains with "silent" gene between non-toxic in Elek-test C. diphtheriae increased. Decreasing of susceptibility to the range of antibiotics is observed in recent years.
Conclusion:
Revealed features of biologic characteristics of diphtheria agent circulating in post-epidemic period should be accounted during epidemiologic surveillance for diphtheria and choice of treatment of the infection.
Related Concept Videos
Diphtheria
Bacterial Phylum Actinobacteria
Atypical Pneumonia
Streptococcal Pharyngitis
Lytic Cycle of Bacteriophages
Acute Pharyngitis
Acute pharyngitis is the inflammation of the back of the throat (pharynx), commonly resulting in a sore throat. It is a frequently encountered condition that prompts individuals to seek medical advice.
Classification
Acute pharyngitis can be categorized based on its underlying cause:

