Causative Agent:-

Infectious Coryza is caused by the bacterium Haemophilus paragallinarum.

Species Affected:-

Chickens, Pheasants, and Guinea fowl.

Clinical Signs

Swelling around the face, foul smelling, thick, sticky discharge from the nostrils and eyes, laboured breathing, and rales (rattles-an abnormal breathing sound) are common clinical signs. The eyelids are irritated and may stick together. The birds may have diarrhoea and growing birds may become stunted. Mortality from coryza is usually low, but infections can decrease egg production and increase the incidence and severity of other diseases. Mortality can be as high as 50 percent, but is usually no more than 20 percent. The clinical disease can last from a few days to 2–3 months, depending on the virulence of the pathogen and the existence of other infections such as mycoplasmosis.

Infectious Coryza

Swelling around the face

Infectious Coryza

Thick-Sticky discharge from the nostrils


Coryza is primarily transmitted by direct bird-to-bird contact. This can be from infected birds brought into the flock as well as from birds which recover from the disease which remain carriers of the organism and may shed intermittently throughout their lives. Birds risk exposure at poultry shows, bird swaps, and live-bird sales. Inapparent infected adult birds added into a flock are a common source for outbreaks. Within a flock, inhalation of airborne respiratory droplets, and contamination of feed and/or water are common modes of spread.

Also, Read: Infectious Bursal Disease in Poultry


Water soluble antibiotics can be used, sulphamethoxazole, azithromycin/ erythromycin or tetracycline can be used as alternative treatments.


  • TETRA PLUS -5 (Tetracycline Hydrochloride Powder 5%): @ 5gm in 4 to 5 litres of drinking water. (Or)
  • PVS-ATH-10 (Azithromycin Powder 10%): @ 1 gm in 1 to 2 litres of drinking water. (Or)
  • COTRIM-FS (Each 5 grams contains: Trimethoprim 160 mg and Sulphamethoxazole 800 mg): @ 1gm in 1 litre of drinking water for 5-7 days.

Supportive therapy in drinking water:

  • BRANCH CARE-DS (Herbal expectorant and bronchodilator): @ 1 ml in 5 litres of drinking water per100 birds for 7-10 days.


Good management and sanitation are the best ways to avoid infectious coryza. Most outbreaks occur as a result of mixing flocks. All replacement birds on “coryza-endemic” farms should be vaccinated.