Prevalence and Antibiogram of Salmonella Species Isolated from Snail (Archachatina marginata) Sold in Port Harcourt, Rivers State, Nigeria

Abstract

Increase in microbial population especially Salmonella species in food due to improper handling, storage and exposure to contaminants can raise public health concerns when consumed without adequate processing. This study evaluates the prevalence and antibiogram of Salmonella species associated with the giant land Snail (Archachatina marginata) sold in markets around Port Harcourt metropolis. A total number of seventy two (72) samples of land snail were collected from three markets; Creek Road, Mile one and Rumuokoro. The samples were labelled and transported in an ice packed coolers to the laboratory for analyses. Standard microbiological protocols were employed to determine the microbial load and species of the various parts (intestine, meat and fluid) of the snail samples after shucking. Antibiotics sensitivity profile testing of the isolated and identified Salmonella species were carried out as recommended by Clinical Laboratory Standard Institute (CLSI) and statistical analyses using one way ANOVA and all pairs Turkey-Kramer. Results from the study showed that the highest total heterotrophic bacteria count (THBC) of 8.6x106CFU/g was obtained in the snail intestine sourced from Creek road market while THBCs  of 8.2x106 CFU/g and 7.3x106 CFU/g were from Mile one and Rumuokoro markets respectively. THBCs of meat from the markets ranged from 4.3-5.4x106 CFU/g and 3.7-4.9x106CFU/ml in fluid with Rumuokoro having the least occurrence respectively. Mean Salmonella counts (MSCs) ranged from 0.4-3.6 x103 CFU/g, with least count obtained from Rumuokoro and Mile 1 markets. Similarly, least MSCs in fluid and intestine were obtained from Rumuokoro and Mile 1 whereas Creek road Market had the highest respectively. Three species of Salmonella; S. arizonae, S. gallinarum and S. typhi were predominant in addition to other species such as Vibrio spp,, Bacillus spp., Staphylococcus spp., Shigella spp., Pseudomonas spp., Enterobacter spp., E. coli, Micrococcus spp., Acinetobacter spp., Klebsiella spp. and Listeria spp identified using both conventional and molecular method. Antibiogram profile revealed that all the identified Salmonella species were susceptible to Ofloxacin and Ciprofloxacin but strongly resistance to Cetazidime and Gentamicin. The diversity and elevated microbial load observed from this study calls for caution in handling and processing of snails since most of these bacteria may become aetiologic agents of several food-borne diseases and other pathological conditions. As a necessity, good quality control measures and proper chemotherapy should be administered to patients with signs and symptoms of food borne illness emanating from consumption of snail.