Gallid herpesvirus 1

Gallid herpesvirus 1 (GaHV-1) (also known as Avian herpesvirus 1)is a virus of the family Herpesviridae that causes avian infectious laryngotracheitis. It was originally recognized as a disease of chickens in the United States in 1926. The disease also occurs in pheasants. GaHV-1 is shed in respiratory secretions and transmitted by droplet inhalation. A previously unexposed flock will develop cases for two to eight weeks following introduction. The incubation period is two to eight days. Symptoms include coughing, sneezing, head shaking, lethargy, discharge from the eyes and nostrils (sometimes bloody), and difficulty breathing. The name comes from the severe inflammation of the larynx and trachea. A diphtheritic membrane may form in the trachea, causing obstruction. Mortality is typically less than 15 percent. A vaccine is available, but it does not prevent latent infections.

The disease is usually referred to as Infectious laryngotracheitis or simply LT in the poultry industry. It is widely viewed as one of the most contagious viruses that affect the poultry industry. A confirmed case will usually result in the establishment of a quarantine zone around the farm. Inside this quarantine zone, poultry workers will avoid poultry farms to prevent the spread of the virus.