[Phage types recognized within Salmonella Enteritidis strains isolated in Poland in 1996-2007].

Unlabelled: Phage typing carried out according to the well-defined schemes is still recommended as a standard, fast and inexpensive method for epidemiological investigations all over the world to control Salmonella infections. However, the method should be in the hands of well-trained staff. This means that it is generally limited to reference laboratories.

Aim: The aim of this study was to perform an analysis of Salmonella Enteritidis phage types occurring in Poland in 1996-2007 basing on the strains received by the National Salmonella Centre for phage typing.

Material And Methods: The phage typing (according to the Lalko et al. scheme) carried out in this research work was associated with 750 Salmonella Enteritidis strains isolated in Poland from human and non-human sources, in the dying out period of over 25 years lasting second epidemic caused by this serovar.

Results: Types 1, 6 and 7 were the most often identified phage types. They were dominant among human as well as non-human (food, feeds, animals, environment and others) isolates. The great majority of them were of type 7. Type 1 Salmonella Enteritidis strains were isolated in the same number as type 6 strains. A little higher number of strains which presented phage type 3 was reported in comparison with the previous periods of time.

Conclusions: It is worth to be noted that except the same, permanent phage types continuously existing in the environment (i.e., 1, 3, 6, 7), the new types start to appear. They can suggest an appearance of new sources of Salmonella Enteritidis infections, unknown in our country yet, which is very possible as a result of effective elimination of currently existing ones. The obtained results constitute the continuation of the previously done studies and provide the essential and unique data which allow to estimate the more completely epidemiological situation associated with occurrence of this pathogen in Poland.