Shigellosis and Development of Multiple Antimicrobial Resistance Mechanisms of Shigella spp.

Abstract

Shigellosis is a serious public health issue. Millions of people suffer from this deadly food and water borne disease each year. The main manifestations of affected persons are bloody diarrhea with excessive dehydration. The causative agent of this disease is the bacteria Shigella spp. which has four serogroups. Though Shigella flexneri and Shigella dysenteriae are the dominant serogroups in developing countries, reports of other serogroups, namely Shigella boydii and Shigella sonnei, in the food contaminations are available. There are seasonal variations of Shigella infection throughout the world. In Asian subcontinent, monsoon and post monsoon times are the ideal for infection. The transmission of the bacteria in human is usually caused by feco-oral route or by contaminated food and water. There are several groups of antibiotics like foscomycin, macrolide, amiglycoside, tetracycline etc. which were used before. But they are now become useless as Shigella spp. is getting resistant against those drugs. The quinolone groups of antibiotics like ciprofloxacin, ofloxacin, norflxacin, ceftriaxone etc. are the important drugs for the cure of the disease shigellosis but prevalence of drug resistant strains of Shigella spp. against those drugs are a great concern nowadays. The occurrence of plasmid mediated quinolone resistance genes (PMQR), efflux pump proteins and effective mutations at drug binding region of gyrA etc. are the major mechanisms for the development of drug resistance.