Disease Alert: Infectious Laryngotracheitis

A clinical case of Infectious Laryngotracheitis (ILT) has been confirmed in a poultry flock in Oxford County. The case was diagnosed on December 11 based on samples submitted to the Animal Health Laboratory at the University of Guelph. OMAFRA is working with the industry and the producer's veterinarian to reduce the risk of ILT spreading to other farms.

Producers are instructed to heighten biosecurity. The service industries, as well as provincially and federally licensed processing plants, are also advised to enhance their biosecurity procedures.

ILT is an acute respiratory disease caused by a herpes virus that can lead to devastating losses in the broiler and layer industries. The disease is most frequently associated with chickens, but can also cause disease in related birds such as pheasants and peafowl. Ontario has experienced ILT outbreaks in the past. The ILT virus does not cause infection in humans.

The mortality rate in affected flocks is usually low, although it can sometimes be more than 20%. Persistent shedding from recovered birds can prolong infection in a flock for a long period of time. The disease is normally characterized by gasping, neck extension, watery eyes (conjunctivitis), swollen sinuses and persistent nasal discharge. In severe cases, violent coughing may be observed, with blood evident in the trachea.

ILT spreads relatively slowly through a flock within 2-4 weeks. The disease is usually spread by people, vehicles or equipment contaminated from an infected farm. Producers must be particularly careful with respect to the disposal of dead birds and manure, as the virus can be spread by these routes. Infected farms are advised to partially compost manure in the barn for at least 3 days prior to removal for complete composting on premises.

Biosecurity is the most important means of prevention. The improper use of vaccines can result in clinical infection and further spread of the disease. Producers should consult their veterinarian to determine the appropriate biosecurity procedures for their operation.