IMMUNOBIOLOGY OF DIPHTHERIA. RECENT APPROACHES FOR THE PREVENTION, DIAGNOSIS, AND TREATMENT OF DISEASE

43 Diphtheria is an acute infectious disease caused by the bacterium Corynebacterium diphtheriae (also known as Klebs-Loffler bacillus) [1]. Typically, diphtheria has respiratory or cutaneous localization. Respiratory diphtheria has various forms, usually restricted to upper respiratory tract: nasal, pharyngeal, tonsillar and laryngeal. As rule, main symptoms of respiratory diphtheria are sore throat, low fever, and an adherent membrane at the site of bacterial colonization [2]. Milder forms of diphtheria are often restricted to the skin [3]. Long time diphtheria was considered as well-controlled vaccine-preventable disease because it has largely been eradicated in all industrialized countries presumably through broad vaccination [4–6]. However, a diphtheria epidemic at the former Soviet Union territory at 1990s has again attracted the attention to incomplete understanding of the epidemio logy, microbiology and especially immunobio logy of this infection [7–12]. Today cases of diphtheria are still occur in Ukraine, Russia, and Latvia and also it is endemic in India, Indonesia, Nepal, Angola and Brazil, but only sporadic cases are repor ted in developed countries [11, 13–16]. Howe ver, the majority of the adult populations in Europe, Australia and the United States have no immune protection against this infection [13, 17]. This issue draws renewed attention to the immunology of this infection, because lowe red immunity levels within population can cause outbreaks of diphtheria.