Studies of Antibiotic Resistance in Bacteria Isolated from Retailed Eggshells in Three Major Markets in Minna, Nigeria

Abstract

Food borne disease associated with inappropriately treated or untreated eggs is a major public health problem affecting developing and developed countries. This study isolated, identified and determined the Antibiogram of bacteria isolates from eggshell of eggs obtained from three major markets in Minna, Nigeria. A total of ten (10) duplicate egg samples were purchased from egg retailers. The egg samples were analyzed for the enumeration and isolation of bacteria. The isolated bacteria were identified using biochemical methods. Antibiotic susceptibility test to prescribed commercially available antibiotic discs was also investigated. The total viable bacteria count (TVBC) ranged from 1.38×104 - 2.52×104 cfu/mL while the total coliform count (TCC) ranged from 8.5×103 - 2.02×104 cfu/mL. Escherichia coli (9.1%), Streptococcus pyogenes (4.5%), Enterococcus sp. (4.5%), Shigella sp. (13.6%), Salmonella sp. (13.6%), Staphylococcus aureus (36.4%), Clostridium sp. (9.1%) and Neisseria sp. (9.1%) were isolated and identified from eggshells. Gram positive bacteria showed highest sensitivity to gentamycin (100%) however, resist cloxacillin, ceftadizime and erythromycin (100%). Similarly, there was no ciprofloxacin resistant Gram-negative bacteria though E. coli, Salmonella sp. and Shigella sp. isolated from eggshells were resistant to augmentin and amoxicillin. Further analysis of result revealed that all the isolated bacteria from eggshells were multidrug resistant except Neisseria sp. with multidrug resistant index greater than 0.2. The fact that these antibiotic resistant bacteria can be transferred to humans is of public health concern. Therefore, stringent use of public health regulations for cleaning eggs before retailing is advocated