Gasping, coughing, rattling and blood-stained feathers around the head and neck are the most common signs of the disease. Sudden death of an individual bird can also be observed and is often the first sign of an ILT infection in the flock.

Reduced productivity is a varying factor in laying flocks. Affected birds are anorectic and inactive. The mouth and beak may be bloodstained from the tracheal exudates. The disease spreads slowly through a flock, and mortality can be high.
After recovery, some birds remain carriers for extended periods and become a source of infection for susceptible birds. The latent virus can be reactivated under stressful conditions.

Two types of live ILT vaccines are commonly available (of Chick-embryo origin or Tissue cell origin). The first ones are normally more invasive than the latter ones, but have a higher residual pathogenicity. One to two vaccinations are usually sufficient to induce life-long immunity, but level of immunity may vary.
In the case of ILT outbreaks an emergency vaccination by eye drop method can cut off the further spread of the virus in an already infected flock. Due to the slow process of spreading through the flock, the emergency vaccination can immunise and protect those birds not yet infected.