Diphtheria

University of Oklahoma Study Abroad Microbiology in Arezzo, Italy[1]

Etiology/Bacteriology

Taxonomy

| Domain = Bacteria | Phylum = Actinobacteria | Order = Actinomycetales | Family = Corynebacteriaceae | Genus = Corynebacterium | Species = C. diphtheria

Description

Corynebacterium diphtheriae is a gram-positive, non-motile, aerobic, and rod-shaped bacterium that causes diphtheria. There are four main subspecies that have been recognized: C. diphtheriae mitis, C. diphtheriae intermedius, C. diphtheriae gravis, and C. diphtheriae belfanti. C. diphtheriae gravis has the fastest generation time out of the four, allowing it to impose its toxic effects sooner. They can all be characterized as toxigenic or non-toxigenic, or those causing diphtheria and those that don’t, respectively. Diphtheria is an upper respiratory tract infection initially resulting in a sore throat and mild fever, but can progress to other more serious symptoms if not treated [1]. It can also infect the skin when lesions are exposed to the bacteria. Even though there are thousands of reported cases each year, the threat of contracting or succumbing to this illness has dramatically decreased due to advancements in antibiotic treatment and development of vaccinations [2].

References

1 Online Textbook of Bacteriology. Diphtheria

2 Burkovski, Andreas (2014). "Corynebacterium diphtheriae" and related toxigenic species: Genomic, Pathogenicity, and Applications. New York: Springer