What is PREVEXXION® RN?
PREVEXXION® RN is the next generation Marek’s Disease (MD) Serotype 1 vaccine. It is the first innovation in this market segment in more than 40 years. PREVEXXION® is the brand name and RN is the short name of the strain, RN1250. This vaccine is a Marek’s Disease chimera consisting of Serotype 1 strains containing two Long Terminal Repeats (LTRs) sequences. It shows a high degree of efficacy against very virulent Marek’s Disease viruses.
Why is it important to vaccinate against Marek’s Disease?
Marek’s Disease is one of the most common and significant immunosuppressive viral diseases in poultry. It causes illness, tumors, death, and poor performance. Marek's Disease cannot be treated; therefore, vaccination is critical for the control of this disease. Vaccination reduces the in vivo challenge virus load after field exposure. Vaccination also dramatically decreases the development of tumors.
What is the main innovation of this new Marek’s Disease vaccine?
Multiple serotype 1 Marek’s Disease viruses and vaccine strains were used in order to obtain the PREVEXXION RN vaccine strain. In addition, specific sequences called long terminal repeats were inserted in the genome of the vaccine strain recognized as safe thanks to its attenuation. The resulting construct is a Marek’s Disease Serotype 1 vaccine RN1250 strain, which has high homology with a Rispens vaccine strain, BUT is not a true Rispens virus. This vaccine is able to immunize against virulent strains of the Marek’s Disease virus and takes advantage of the safety of existing vaccines. PREVEXXION RN has the right balance between safety and efficacy.
When does PREVEXXION RN clinical protection start and how long does it last?
- Onset of immunity: from five days of age.
- Duration of immunity: Long‐lasting immunity even for long life birds, like classical serotype 1 vaccines.
ADDITIONAL FAQ
What makes the PREVEXXION RN efficacy pattern reliable?
The PREVEXXION RN vaccine was proven to be protective as early as the first week of life when challenged. The LTR insertion likely contributes to the safety profile, meanwhile, it does not impact the working mechanisms of a Serotype 1 Marek’s Disease vaccine.
How can PREVEXXION RN be administered?
The vaccine can be administered in the controlled environment of the hatchery, either by: In-ovo injection (at 18‐19 days of incubation), or Subcutaneous injection in healthy day‐old chicks
What are the storage conditions of this vaccine?
PREVEXXION RN is a frozen live vaccine, therefore, it must be stored in liquid nitrogen. At the time of launch, the expiration date will be 24 months after the manufacturing date. But eventually we expect to have as long a shelf life as has the current Rispens vaccine range.
In what type of birds can PREVEXXION RN be used?
- Long life broilers
- Breeders
- Layers