Delhi sees rising number of bird breeder’s lung disease cases; doctors say no to pigeon breeding

It is a type of hypersensitivity pneumonitis (HP) triggered by exposure to highly antigenic avian proteins excreted in bird droppings and waxy proteins covering feathers of a variety of birds (bloom) which provokes a hypersensitivity reaction in a susceptible host. Despite being one of the most common types of hypersensitivity pneumonitis, it is often an underdiagnosed condition.

Dr Vikas Maurya, director and HOD of pulmonology at Fortis Hospital, says that cases of hypersensitivity pneumonitis, or bird breeder’s lung disease increased in India in 2017.

The study published in 2017 in Indian Pediatrics (IP), the official publication of the Indian Academy of Pediatrics (IAP), said that Pigeon breeders’ disease usually affects adults but children are more likely to be affected when they share living space with a backyard poultry or pigeon breeding.

The doctor advises to avoid the breeding of pigeons predominantly because most hypersensitivity pneumonitis is caused by bird breeders, for example, pigeons. “We say no to pigeons because obviously, it can cause very severe, debilitating diseases like hypertension and pneumonitis, which can cause interstitial lung disease or fibrotic lung disease,” says Dr Maurya.

Dr Maurya says that in India, the main cause of influenza-like illness is hypersensitivity pneumonitis, followed by other causes like connective tissue disorders and other diseases. “And this is what we have found, that there has been an increase in the number of patients with hypertensive pneumonitis in Delhi as well, and this has been well documented in many studies also,” he says.

According to Dr Neeraj Gupta, the diagnosis was not very high earlier as there was confusion with some other diseases but with more awareness, advancing knowledge and various publications in this regard, even the pulmonologists are more aware of the condition and the diagnosis is more now as compared to previous years.

“We do come across cases in our OPDs and such incidents are more spotted by tertiary care doctors. When a person who is feeding birds, or exposed to bird excreta, at their work or residential place, they are prone to develop the disease,” says Dr Gupta.

He adds that doctors specifically ask questions about the area they live in, whether they have birds at home if they are bird watchers etc.

Dr G C Khilnani, chairman of PSRI Institute of Pulmonary, Critical Care and Sleep Medicine, says that he is seeing more cases of bird breeder’s lung disease in the last couple of years than ever before.

“In my personal experience, I am seeing it more often in the last couple of years. I do not have any organised data but we are seeing such cases these days.

He says that it is not a common disease and often it is not diagnosed for years together.

“Those who feed birds on crossings are more prone to developing the disease and the pigeon droppings in the balconies can cause health issues such as interstitial lung disease (ILD). This type of ILD is most common in India,’ says Dr Khilnani.