Prevexxion RN

Prevexxion RN is available as a concentrate and solvent to be made into a suspension for injection and can only be obtained with a prescription.

The vaccine can be given to one-day-old chicks as a single injection under the skin in the neck. Protection starts 5 days after vaccination and lasts for life.

For more information about using Prevexxion RN, see the package leaflet or contact your veterinarian or pharmacist.

Prevexxion RN is a vaccine. Vaccines work by ‘teaching’ the immune system (the body’s natural defences) how to defend itself against a disease. Prevexxion RN contains small of amounts of modified MD virus which does not cause disease in chickens but which is similar to the virus that causes MD. When Prevexxion RN is given to chickens, their immune system recognises the virus as ‘foreign’ and makes antibodies against the virus. In the future if the animals are exposed to a similar MD virus, the immune system will be able to respond more quickly. This will help protect the chickens against MD.

Prevexxion RN was investigated in 3 laboratory studies and 2 field studies.

The studies showed that Prevexxion RN prevents death and clinical signs of MD and reduces lesions caused by MD virus, including very virulent MD virus. Data from studies indicate that birds were protected against MD from the 5th day after vaccination and this protection is lifelong.

Since Prevexxion RN is a live vaccine, the vaccine strain may be passed into the environment from vaccinated chickens but has not been shown to spread under experimental conditions. However, precautionary measures must be followed to avoid spread of the vaccine strain to unvaccinated chickens and other susceptible species.

There are no known side effects when used at the recommended dose. For the full list of restrictions, see the package leaflet.

Safety information has been included in the summary of product characteristics and the package leaflet for Prevexxion RN, including the appropriate precautions to be followed by healthcare professionals and animal owners or keepers.

As the vaccine is stored in liquid nitrogen, it is important that any handling is done in a well-ventilated area and that precautions are taken when preparing the vaccine. For further information see the summary of product characteristics.

The withdrawal period is the time required after administration of a medicine before an animal can be slaughtered and the meat used for human consumption. It is also the time required after administration of a medicine before eggs may be used for human consumption.

The withdrawal period for meat and eggs from chickens treated with Prevexxion RN is ‘zero’ days, which means there is no mandatory waiting time.

Prevexxion RN has been shown to prevent or reduce signs of Marek’s disease and death in vaccinated chickens. There is no evidence that the vaccine harms chickens, the users or the environment. The European Medicines Agency therefore decided that Prevexxion RN’s benefits are greater than its risks and it can be authorised for use in the EU.

Prevexxion RN received a marketing authorisation valid throughout the EU on 20 July 2020.