>U.S. Pat. No. 10,130,701)
Read the whole patent. It's about vaccines for chickens:
https://patents.justia.com/patent/10130701
FIELD OF THE INVENTION
The present invention relates to an ''attenuated coronavirus comprising a variant replicase gene'', which causes the virus to have reduced pathogenicity. The present invention also relates to the use of such a coronavirus in a vaccine to prevent and/or treat a disease.
BACKGROUND TO THE INVENTION
Avian infectious bronchitis virus (IBV), the aetiological agent of infectious bronchitis (IB), is a highly infectious and contagious pathogen of domestic fowl that replicates primarily in the respiratory tract but also in epithelial cells of the gut, kidney and oviduct. IBV is a member of the Order Nidovirales, Family Coronaviridae, Subfamily Corona virinae and Genus Gammacoronavirus; genetically very similar coronaviruses cause disease in turkeys, guinea fowl and pheasants.
Clinical signs of IB include sneezing, tracheal rales, nasal discharge and wheezing. Meat-type birds have reduced weight gain, whilst egg-laying birds lay fewer eggs and produce poor quality eggs. The respiratory infection predisposes chickens to secondary bacterial infections which can be fatal in chicks. The virus can also cause permanent damage to the oviduct, especially in chicks, leading to reduced egg production and quality; and kidney, sometimes leading to kidney disease which can be fatal.