Isolated strain belonging to a new Salmonella serotype

The National Reference Center and OIE for salmonellosis of the Istituto Zooprofilattico Sperimentale of Venice (IZSVe) has identified a strain of salmonella attributable to a serotype never described before.

The new entry is called Salmonella Abeokuta and is originally from Nigeria.

At the time of identification, the Salmonella strain did not match any of the more than 2,600 serotypes known to date and encoded in the White-Kauffmann-Le Minor scheme, used to name the Salmonella strains. The serotype was isolated from a chicken feed sample in southwestern Nigeria, in Abeokuta, the capital of Ogun state. It was then sent to the European reference laboratory for salmonella in Bilthoven (Netherlands), and then to the Pasteur Institute in Paris for further investigations.

The confirmation came a few weeks ago: the strain actually belongs to a new serotype, not yet codified.

The story of this discovery began eight years ago, when the IZSVe hosted a Nigerian colleague for a training period at the Reference Center.

Dr. Idowu Oluwabunmi Fagbamila, serving at the National Veterinary Research Institute in Vom (Nigeria), provided the Salmonella strains from that area for identifying the strain. The merit of the discovery, in addition to Dr. Fagbamila, also goes to Claudio Minorello, a laboratory technician now retired but until a few years ago worked at the Reference Center, where he dedicated most of his activity to the serotyping of Salmonella.

Abeokuta has not been identified in other countries outside Nigeria, nor does it appear to be a cause for concern for animal and human health to date. The monitoring and control actions by the Reference Center will help to understand the health relevance of this and any new strains of Salmonella.

The current Kauffmann-White-Le Minor classification system is based on the antigenic determinants of the various Salmonella serotypes and it was built in over 80 years of research on the interactions between antibodies and surface antigens of the bacterium: the scheme contains the antigenic formulas of all known Salmonella serotypes.

The program is maintained and updated by the World Health Organization (WHO) Salmonella Reference Center at the Pasteur Institute in Paris.

When it was first published in 1934, the scheme included only 44 serotypes, while today they are 2,659, according to the last update in 2010.

Source:   IZSVe