BENGALURU: Mumbai’s pulmonologists have linked a worrying rise in cases of fibrotic lung disease hypersensitivity pneumonitis or ‘bird breeder’s lung’ to the city’s exploding pigeon population. India’s Silicon Valley Namma Bengaluru has the same problem, although no deaths have been reported.
Dr Satyanarayana Mysore, HOD and Consultant - Pulmonology, lung transplant physician, Manipal Hospital - Old Airport Road, said, “Pigeon fancier’s disease has been known for ages. Pigeon droppings incite a very pronounced immune response which may lead to injury in the lung. In response to this injury, the reparative process becomes quite well pronounced, and can lead to scarring of the lung.”
“Scars prevent good contraction or expansion of the lung, and also limit the point of how much oxygen and carbondioxide can be exchanged at the basement membrane of the lung. Definitely, this is a correlation done over many years, 20 to 30 years at best, and there’s lots of literature linking birds, especially pigeons, with disability in the lung,” Dr Satyanarayana said. “Since the outcome of the process is visible over years, people may not experience symptoms to begin with. It may be labelled bronchitis because they have cough and expectoration (sputum or phlegm production) which may be very intermittent. However, once the scarring process starts, we label it hypersensitivity pneumonitis (HP). The scarring is more evident on the upper portion of the lung, compared to the bottom of the lung which usually gets spared due to aerodynamics.”
Dr Sandeep H S, Consultant Pulmonologist, BGS Gleneagles Global Hospital, said there are many causes of hypersensitive pneumonia, however, in the cases he has treated, the patients were either pigeon feeders or lived in close proximity to pigeons.
Just being exposed to pigeons or their droppings once or twice may not lead to hypersensitive pneumonia, but prolonged exposure does, he said. “Those who feed pigeons on a regular basis, or are exposed to the birds which are regular visitors to homes, balconies and spaces around their buildings, and inhale pigeon droppings, will have a problem,” said Dr Sandeep.
Dr Sandeep has previously worked in Mumbai, where pigeon feeding is common and has reported the highest caseload of HP. Bengaluru is also picking up the habit, and widespread public awareness is the key to keep the disease at bay.
“HP can be divided into three stages. In the first two stages -- acute and subacute -- it is mild and treatable with steroids. However, in the chronic stage, damage to the lungs is extreme and irreversible. A majority of patients reach us in the chronic stage only,” said Dr Sandeep.
He said there are no standard rules on handling pigeon droppings in the city.
What are the treatment options?
Initial doses of steroids may provide some relief. However, long-term prognosis is probably not preventable. Some of the serotypes of pigeons may respond to doxycycline, and may be combined with steroids, Dr Satyanarayana said.
Both Dr Satyanarayana and Dr Sandeep said that prevention is better than cure, and birds should be set free in the atmosphere. Prevention lies in not breeding the birds or wanting to keep them as pets.
No law prohibits feeding
There are many pigeon feeders who head to multiple pigeon feeding spots across the city, including parks, playgrounds and public spaces. They feed them grains of wheat, rice, ragi, bajra, maize and pulses. They also feed leftovers like cooked rice.
“I have been feeding pigeons and crows every day for more than two decades. I feel my day is complete only if I feed the birds. The feel of the birds flying towards you after you throw the feed gives satisfactionm” said Sampath Raj, a bird feeder.
However, there are people who have a problem with feeding of birds in public, as the place gets dirty. There have been many instances where the Bruhat Bengaluru Mahanagara Palike (BBMP) and other organisations have put up boards, asking people not to feed birds. When faced with the wrath of citizens, they pulled the boards down.
Animal rights activist Arun Prasad said, “Birds like pigeons are scavengers, and capable of finding their own food. They earlier found their feed in agricultural fields and trash bins. However, there are hardly any open fields in the city and as waste is collected at source, pigeons are deprived of that option too. So where should their food come from? They are dependent on humans who have exploited their source of food.”
“As of now, there are no guidelines by the Union and state governments on bird feeding. From time to time, the Union Ministry of Health and Family Welfare updates the list of zoonotic diseases of public health importance. Zoonotic diseases spread from animals to humans, like rabies, anthrax, zika virus, plague, leptospirosis, ebola etc. The recent coronavirus is also listed. They have not listed any disease related to pigeons, as they haven’t found them in large numbers,” Prasad explained, and requested people not get scared about pigeons and feeding them.
He also took objection to the scare created by people and doctors, that pigeons are the sole reason for health problems. “As of now, there is no law that bars people from feeding pigeons. As humans, it is our duty to feed pigeons and other birds and the government has no right to stop it. If the government imposes restrictions on feeding, it will be a direct violation of Article 51A(g) of the Indian Constitution, which states that the natural environment, including forests, lakes, rivers and wildlife should be protected and improved, and to have compassion for living creatures. Putting up boards and banners prohibiting feeding is against the guidelines of the Animal Welfare Board of India,” he added.
If people don’t feed birds and animals, the onus is on the government to feed them. Prasad said we should learn to co-exist with nature, birds and animals.
What ornithologists, ecologists say
As health concerns rise among medical experts and citizens, there is a mixed response among ornithologists and environmentalists. Pointing out that pigeons have adapted to architectural facades that have created safe roosting habitats, they say there is an urgent need for architects to be sensitive to environmental needs.
Noted environmentalist MB Krishna said pigeons are not alien to the city. Rising multi-storey buildings in urban areas prove suitable and safe habitats, leading to a rise in their population. Multi-storey buildings with ledges are ideal for them. Citizens should come up with out-of-the-box ideas and initiatives to keep pigeons at bay, like more green spaces, having more creepers and even nets on all structures.
Environmentalists have advised architects to change their structural design and planning to keep pigeons at bay. “Pigeons are a menace because of our own lifestyle. Ultra-modern architecture, without environmental knowledge, is leading to a rise in pigeon numbers. Horizontal facades with protrusions need to end. Construction of dome-like tower structures also needs to stop to ensure that pigeons’ roosting spaces are reduced,” the environmentalist said.
Noted ornithologist Dr S Subramanya pointed out that since there is no natural predator to hunt down pigeons, they are on the rise. Present-day architecture is another cause for concern. In Montreal, Peregrine Falcons hunt pigeons. But in India, they are migratory birds. They breed all through the year, and it takes 2-3 months per brood. There is, thus, a need for preventive barriers. Pigeons are not new, they were earlier found in Nandi Hills and are still found there as rock pigeons. Over time, they have moved to urban areas and adapted to urban life.
The environmentalist added that the problem is that many people feed pigeons. Some religious beliefs deem it a holy act. Despite the Karnataka High Court taking cognizance of this, feeding pigeons continues unabated in Cubbon Park and other places in Bengaluru. Dwellers of many apartment complexes in Bengaluru have been complaining to environmentalists and ornithologists, seeking solutions to end the pigeon menace. They point to their droppings, falling feathers and even their cooing. Pigeons are also a menace in Metro stations, under flyovers and underpasses.
Ashwin Vishwanatham from the Nature Conservation Foundation said there has been a 100 per cent rise in their population in the past 20-30 years. There is a need to conduct detailed research on the impact. Case studies in some pockets, like Mumbai, have shown that people’s health, especially their lungs, is affected because of pigeons, but the same impact in larger areas is still being studied.
KEEPING PESTS AT BAY
1. Do not keep balconies empty, have pots and creepers
2. Keep balconies free of garbage or any waste
3. Put nets in case of high rises
4. Plant native species around