A broad spectrum HVT-H5 avian influenza vector vaccine which induces a rapid onset of immunity.

Current methods to combat highly pathogenic avian influenza (HPAI) outbreaks in poultry rely on stamping out and preventive culling, which can lead to high economic losses and invoke ethical resistance. Emergency vaccination could be an alternative as vaccination is one of the most efficient and cost-effective measures to protect poultry from HPAI infection, preventing spreading to other poultry and greatly reducing the potential transmission to humans. Current conventional inactivated AI vaccines may be useful for combating AI outbreaks, but do not fulfil all targets of an ideal AI vaccine, including mass applicability and rapid onset of immunity.

Efficacy of a turkey herpesvirus double construct vaccine (HVT-ND-IBD) against challenge with different strains of Newcastle disease, infectious bursal disease and Marek's disease viruses.

A double construct vaccine of turkey herpesvirus (HVT) was prepared that contains the fusion (F) gene from Newcastle disease virus (NDV) and the viral protein 2 (VP2) gene from infectious bursal disease virus (IBDV). Safety of the vaccine (HVT-ND-IBD) was confirmed and efficacy was evaluated after subcutaneous (SC) vaccination at 1 day of age or the route of vaccination. Challenges were performed with velogenic NDV strains (Texas GB and Herts Weybridge 33/56), with different strains of IBDV (classical strain STC; very virulent strain CS89 and variant E strain) and with Marek's disease virus (MDV) strain RB1B.