PARASITOLOGICAL SURVEY AND ANTIMICROBIAL SUSCEPTIBILITY PATTERNS OF MICROBIAL ISOLATES FROM PRE WASHED FRUITS AND VEGETABLES COLLECTED IN METTU TOWN, I/A/BORA ZONE, SOUTHWEST ETHIOPIA

Background: Intestinal parasitic infections are widely distributed throughout the world causing substantial intimidation to the public health, economy, and physical and cognitive development particularly among children in developing countries like Ethiopia. Fruits and Vegetables may be contaminated at any point during growing, harvesting, sorting, packaging, and storage. This study was aimed at assessing parasitological survey and antimicrobial susceptibility patterns of microbial isolates from fruits and vegetables collected in Mettu town, Ethiopia from March –October, 2018.Methods:A cross sectional study design was conducted. A total of 240 fresh fruits and vegetable samples were collected on different days from local markets. Four types of fresh vegetable comprising lettuce, carrot, tomato, green pepper and two type fruits comprising lemon and banana were collected from selected local markets. For microbiological analyses, 25g of sample was aseptically weighed and washed gently in 225ml of sterile 0.1% (w/v) peptone water (Oxoid) for 3 minutes. Bacterial isolation and antimicrobial susceptibility was performed. For parasitological survey a portion fruit and vegetable was washed separately in 500 mL of normal saline for detaching the parasitic stages (ova, larvae, cysts) of helminthes and protozoan parasites commonly assumed to be associated with vegetable contamination. After overnight sedimentation of the washing solution, 15 mL of the sediment was then transferred to a centrifuge tube using sieve, to remove undesirable matters. For concentrating the parasitic stages, the tube was centrifuged at 3000 rpm for five minutes. After centrifugation, the supernatant was decanted carefully without shaking. Then the sediment was agitated gently by hand for redistributing the parasitic stages. Finally, the sediment was examined under a light microscope using ×10 and ×40 objectives.  Results: A total of 240 samples of fruits and vegetables were collected from the local markets and examined for microbial isolate and parasite contamination .A total of 196 bacterial isolates of eight genera were identified. Klebsiella spp. 40(20.4%) was the most dominant followed by Citrobacter spp. 38(19.4%), Enterobacter spp. 32(16.3%), E. coli 24(12.2%), Salmonella spp.22 (11.3%), Proteus spp.20 (10.2%), S. aureus 20(10.2%), More than 90% of microbial isolates were resistant for Ampicillin and amoxicillin. All the S. aureus isolates were sensitive to oxacillin and vancomycin. Nearly 93.8% of the isolates were sensitive for ciprofloxacillin. whereas 41.5 % of the isolates showed resistance to oxytetracycline.. Resistance to nitrofurantoin, nalidic acid, streptomycin, chloramphenicol, cotrimoxazole, ceftriaxone, kanamycin and Gentamycin were 30.7%,28.4%,19.9%,17%,11.4%,14.8%,10.2%, 6.8% respectively. The results of parasitological examination showed that 100 samples were identified to be microscopically positive  with at least one type of parasite, which gave rise to the overall contamination rate of 41.7%. The stages and species of parasites detected include ova of Ascaris lumbricoides(32%), Hymenolepis nana(16%), and cysts of Giardia lamblia(28%), and Entamoeba histolytica/dispar(24%).

Conclusion: Fruits and vegetables in Mettu local markets were significantly contaminated with potentially pathogenic bacteria, multiple antibiotics resistant and the potential source of transmission for intestinal parasites to humans. Prevention of contamination remains the most effective way of reducing food borne parasitic infection. A comprehensive health education should be given to vendors and farmers of fruits and vegetables and to the general population on the health risks associated with consumption of contaminated fruits and vegetables. Further studies should be conducted on the viability of parasitic contaminants of fruits and vegetables. Also, other researches must be done to evaluate the level of parasitic contamination of farm produces, water, and soil.

Key words: Parasitological survey, vegetable, microbial isolate, antibiotic resistance , Mettu