Development and use of the H strain of avian infectious bronchitis virus from the Netherlands as a vaccine: a review

The H strain of infectious bronchitis (IB) was one of the earliest live attenuated IB vaccines to be developed and has continued to be use in most parts of the world for almost 50 years. It was developed for used at both the 52nd (H52) and 120th (H120) vaccine levels and, because of it ability to provide heterologous cross-protection against a number of IB viruses of different serotypes, has proved to be one of the most enduring live attenuated...