March 24, 2023
Turkey herpes virus vaccines found to be effective against highly pathogenic avian influenza in hens, study reveals
A research conducted by Wageningen University & Research (WUR; the Netherlands) attested that two turkey herpes virus (HVT)-H5 vaccines were effective against highly pathogenic avian influenza (HPAI) in laying hens.
The vaccines can be administered in eggs or to day-old chicks in the hatchery. Researchers observed that both vaccines were able to prevent 100% of the disease, mortality after infection and virus spread among birds with HPAI H5N1 virus.
The study tested the efficacy of four commercial vaccines from veterinary medicine companies on laying hens: a HVT-H5 vaccine by Ceva Sante Animale, a HVT-H5 vaccine by Boehringer Ingelheim Animal Health, a DNA vaccine from Huvepharma and Nobilis vaccine by Merck Sharp & Dome (MSD).
The study was aimed at determining whether the virus would spread from infected to uninfected chickens. Each vaccine was administered to 10 laying hens, five infected with HPAI and five uninfected. The two HVT-H5 vaccines were demonstrated to b 100% effective.
The researchers did not evaluate whether the vaccines are effective in preventing the disease after HPAI infection has already occurred.
"The so-called HVT-H5 vaccines offer protection against disease symptoms in laying hens and prevent the spread of the virus", explained Nancy Beerens, head of the National Reference Laboratory for Avian Influenza and Newcastle Disease at Wageningen Bioveterinary Research (WBVR).
According to Beerens, the study results do not mean the vaccines are effective in poultry farms. However, the Dutch Ministry of Agriculture, Nature and Food Quality plans to conduct an in-depth field study in the summer of 2023.
"It is important to test whether vaccines work well under field conditions on poultry farms, how long the vaccines protect and whether one vaccination is sufficient," Beerens added. "There are still some hurdles to overcome, but the results of our research are an important first step toward vaccination against avian influenza virus in poultry".
- EFA News