Gastrointestinal carriage of Salmonella species and intestinal parasites, and nasal and hand carriage of Staphylococcus aureus among asymptomatic food handlers

Abstract

Background: Food borne diseases continue to be a public health problem globally. Food handlers (FHs) have been implicated in food borne outbreaks. Asymptomatic carriers go unnoticed and are thus an important source of pathogens. Aims and Objectives: This study was conducted to detect intestinal carriage of Salmonella species and parasites as well as nasal and hand carriage of Staphylococcus aureus (S. aureus) among asymptomatic FHs. Personal hygiene practices followed by them were recorded. Materials and Methods: A total of 300 asymptomatic FHs were studied. A semi-structured questionnaire was filled. Nasal swabs and finger impressions were taken on mannitol salt agar plates which were incubated overnight at 37°C; colonies suggestive of S. aureus were identified and confirmed by standard biochemical tests. Stool culture for Salmonella species was done on MacConkey agar, Xylose Lysine Deoxycholate agar and simultaneously inoculated in Selenite F broth for further processing; colonies suggestive of Salmonella species were identified by standard biochemical tests and Salmonella antisera (Denka Seiken, Japan). Stool-routine/microscopy for parasites was done by gross examination, direct saline, and iodine mount followed by concentration method (saturated salt solution). An arbitrary 10-point scale used in earlier studies was utilized for classifying the level of personal hygiene of FHs. Results: Salmonella Typhi was detected in stool culture of two FHs. Intestinal parasites detected in 10 (3.3%) subjects, included Ascaris lumbricoides (5;1.7%), Entamoeba histolytica (3;1.0%), and Giardia intestinalis (2;0.66%). S. aureus carriage was noted in anterior nares (116;38.7%) and hand (83;27.7%). A total of 149 (50%) FHs were S. aureus carriers. Conclusion: This study indicates that FHs may be a potential source of food borne pathogens.