Infectious Laryngotracheitis (ILT) is a herpesvirus infection of chickens, pheasants, peafowl and turkeys. The effects of this disease are largely commercial as it can cause deaths and affects productivity.

If notifiable disease is suspected, contact the DAERA Helpline on 0300 200 7840 or your local DAERA Direct Regional Office. Failure to do so is an offence

How is ILT spread?

Pathogenicity can vary with morbidity of 50-100 per cent and mortality usually 10-20 per cent but sometimes up to 70 per cent.  Transmission between farms may occur by airborne particles or fomites.  The virus is highly resistant outside the host but is susceptible to disinfectants. Movement and mixing of stock and reaching point of lay are predisposing factors.

Litter has been identified as a key risk factor in infection spread. We continue to urge industry to store litter for as long as practically possible before spreading it and to keep litter trailers covered.

ILT is a notifiable disease.

Implications for human health and food safety

There are no human health or food safety implications associated with ILT.

Signs in poultry

  • dyspnoea
  • gasping
  • coughing of mucus and blood
  • drop in egg production
  • ocular discharge
  • sinusitis
  • nasal discharge (low pathogenicity strains)
  • post-mortem lesions (Severe laryngotracheitis, often with blood in lumen; caseous plugs may be present)

Latest Situation

14 July 2021

There have been thirty cases of ILT reported by Private Veterinary Practitioners (PVP) in Northern Ireland since 4 May to date.

The last outbreak of ILT was in 2013.  ILT is a notifiable disease in Northern Ireland, however DAERA considers it a production disease therefore no restrictions or actions at flock level are currently being carried out.

Good biosecurity and practices similar to those used for an Avian Influenza (AI) incursion are essential to keep commercial and backyard flocks free from this serious viral infection.  Bird keepers are encouraged to maintain high levels of biosecurity and continue to use the Biosecurity Checklist.  Good biosecurity is essential for the health of your birds and to prevent any risks of disease spread.

  • Please see guidance produced by the NI Poultry Industry Federation for commercial and backyard keepers found here.
  • A map showing the zones around the premises where ILT has been reported can be found here.

Text alert service

By signing up to our text alert service you can keep up to date with the latest news. You will receive immediate notification of any disease outbreak or other important disease information, enabling you to protect your flock at the earliest opportunity.

Subscription is easy. Simply text ‘BIRDS’ to 67300

The text alert service privacy notice explains how DAERA will use and protect your personal information in relation to the Avian Influenza Text Alert service.


There is no treatment but antibiotics can be used to control secondary bacterial infection if this is marked.


Methods of prevention include strict biosecurity, quarantine or all-in/all-out operation. In the event of an outbreak vaccination of poultry over 4 weeks of age on affected sites would be considered on a case by case basis. Importation of vaccine and the use of vaccine is controlled by DAERA.  Susceptible stock should be kept separate from vaccinated or recovered birds. Strict biosecurity should also be applied when moving equipment or materials between these categories of stock.  

Farmers are asked to contact their Private Veterinary Practitioner (PVP) if they suspect that their flock has been infected.

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