Zoonosis control is one of Europe’s priorities. Foodborne origin zoonosis like Salmonella and especially Salmonella Enteritidis and Salmonella Typhimurium are part of an official control program implemented in poultry farms for a couple of years. Biosecurity measures, cleaning & disinfection and vaccination are the key actions to be implemented in order to reduce the transmission of these two pathogens to human beings with poultry meats and eggs.

Ceva Santé Animale (Ceva), the French animal health company, world leader in poultry vaccination, registered in Europe a live attenuated Salmonella vaccine: Cevac® Salmovac for layer & breeder pullets for active immunization of chickens to reduce colonization, persistence and invasion of the intestinal tract and internal organs by Salmonella Enteritidis and Salmonella Typhimurium.

Ceva was granted on August 06th 2023 in the European Union and the UK for an update claim on differentiation methods of the Cevac® Salmovac salmonella vaccine strain from field Salmonella Enteritidis strains.

Three methods are now available for diagnostic laboratories:

• Ceva S-Check, a Ceva kit which consists of 2 vials of culture media. Medium A without Adenine and Histidine and Medium B with Adenine and Histidine. The vaccine strain due to it’s auxotrophy for Adenine and Histidine is only growing in Medium B while field strains will grow in both vials.

• Chromogenic media, like ASAPTM Biomérieux. This chromogenic media can be used as second culture media in parallel of XLD media as described in the ISO 6579/2017 reference method. On this ASAPTM media Cevac® Salmovac colonies are dark blue purple while field SE ones are getting a pink color. 
• PCR methods: commercial PCR kits are available on the European market allowing differentiation of vaccine strain from field SE due to specific mutation point in the vaccine genes.

Diagnostic laboratories running Salmonella control analysis from poultry farms in European Union and the UK have now in their hands three different methods according to their laboratory facilities (culture or molecular biology). This is allowing to get a quick reliable answer about the Salmonella strain isolated from farms vaccinated with Cevac® Salmovac.