RAPD/PCR AND PHAGE TYPING OF SALMONELLA ENTERITIDIS ISOLATED FROM POULTRY AND FOOD POISONING OUTBREAKS

Abstract

ABSTRACT Salmonella Enteritidis (SE) is an important pathogen, causing both food poisoning outbreaks in humans and economic losses to the poultry industry, being also widely spread in the environment. This work aimed to identify SE phage types and to standardize the Random Amplified Polymorphic DNA (RAPD) for evaluating SE isolates obtained from different origins. To do so, 238 SE strains were selected, of which 104 were isolated from broiler carcasses, 106 from food samples and human biological materials involved in food poisoning outbreaks and 28 from different poultry materials. Among these 238 SE isolates, 111 were phage typed, and 57.7% (64/ 111) corresponded to phage type (PT) 4, 32.4% (36/111) to PT 4a, 3.6% (4/111) to PT 6a and 0.9% (1/111) to PT 7, whereas 5.4% .6/111) of the strains were not typeable (RDNC, reacts but does not conform). After the standardization of amplification conditions, all 238 SE isolates were submitted to RAPD/PCR. Among these, 91.8% (217/238) were classified as pattern A. Twenty-one isolates were differentiated into four patterns and into seven subtypes with the use of primer 1254, and into four patterns and ten subtypes using primer OPB 17. The combination of phage typing and RAPD/PCR proved to be a useful tool in epidemiological investigations. RAPD/PCR can be easily used as a routine laboratory method, thus helping with the monitoring of SE isolates and contributing to the establishment of effective Salmonella Enteritidis control and preventive programs.