Animal health firm Zoetis has said the first specific vaccine against the QX strain of infectious bronchitis is now available in the UK.

Previously, the vaccine, Poulvac IBQX, required a special import certificate from the Veterinary Medicines Directive that would only be issued for flocks where the QX strain had been isolated.

The QX variant of infectious bronchitis has been an increasing problem in European countries over the past 10 years and was first seen in the UK in south-east England in 2007. Since then, QX has been isolated from a number of commercial layer and broiler flocks, leading to drops in performance and increased mortality.

See also: Free carcass quality guide released by Aviagen

The Poulvac IB QX vaccine is based on a live attenuated virus and is most commonly administered as a coarse spray to broilers from one-day old and to layer pullets or broiler breeders from seven days of age. Protection has been demonstrated by challenge study to last for 63 days after vaccination.

“In countering the QX virus strain, some existing vaccines have been used to provide a degree of cross-protection,” said Dr Stuart Andrews, poultry veterinary manager for Zoetis. “However, it is important to appreciate that Poulvac IB QX is a vaccine homologous to any IB QX field strain and so will provide even better protection.

“Furthermore, our in-house PCR and DNA sequencing service allows us to monitor carefully the field situation to ascertain which IB strains are currently causing field outbreaks and enable us to recommend adaptations to particular vaccination programmes.

“The full approval for the Poulvac vaccine will make it easier and more effective to tackle specific QX infections without having to apply for an import certificate.”