The IB virus is known to mutate very easily, so almost every year new cases emerge with different variants.

In an online interview held on Friday (5/12), the Poultry Indonesia team spoke with Muhammad Abdillah, Branch Manager of Elanco. He explained that Infectious Bronchitis (IB) is an acute respiratory disease in chickens caused by a virus from the Coronavirus group.

“The characteristics of this virus make it very prone to change, which is why in the field we find many variants. Some attack only the respiratory tract, while others affect the kidneys and digestive system. Transmission is also extremely fast—even one sick chicken can infect up to 30 others in the same house,” he explained.

According to Abdillah, distinguishing IB symptoms during the pre-production and production phases is not easy, nor is differentiating IB from other respiratory diseases.

“The challenge is that the early symptoms resemble those of other respiratory diseases such as aMPV, SHS, or AI subtype H9. That’s why awareness in the first seven days is crucial. If chickens start showing signs of rales or noisy breathing, it is best to immediately call a veterinarian so the disease does not spread easily.”

In young layer chickens, IB infection—especially during the first week—can trigger the risk of false layer syndrome, which impacts future production performance. Meanwhile, in laying hens already in production, certain micropathogenic strains can cause decreased eggshell quality, watery albumen, and reduced egg production.

“For diagnosis, veterinarians must first conduct an anamnesis. We need to look at the history: Is it a multi-age flock or not? How many days have the symptoms been present? Then we perform necropsy and take blood or organ samples. You can’t diagnose it just by guessing from the sound of coughing,” he said.

The clinical signs of IB can be categorized into three forms: respiratory, reproductive, and renal (damage to the urinary system). The symptoms that appear depend on which organ is infected. In general, the initial signs are quite common, such as sneezing, coughing, rales, and watery eyes.

“There are also IB strains that attack the reproductive system in laying hens. In terms of both quality and quantity, egg production will definitely decline. Typically, the eggshells become pale, thin, rough, or even shell-less. The eggs produced are also smaller, and in some cases their shape is irregular.”

This article is an excerpt from the Health section of Poultry Indonesia magazine, January 2026 edition. Read the full article in Majalah Poultry Indonesia Edisi Januari 2026. For subscriptions or further information, please contact: https://wa.me/+6287780120754 or sirkulasipoultry@gmail.com.

Get more information about the Indonesian poultry industry by joining our WhatsApp Channel,  WhatsApp Channel Satwa Media Group.