What Diseases Can Pigeons Carry to Humans?

Pigeons harbor dozens of organisms capable of infecting people, but the number that actually make the jump is far smaller than the raw pathogen count suggests. A large review of pigeon disease data estimated that about 17% of sampled pigeons worldwide carry at least one zoonotic pathogen, with the highest rates in Asia and the lowest in the Americas.¹ The gap between what pigeons carry and what they actually pass to people is wide, but the diseases that do cross over can be serious, especially for anyone with a weakened immune system.

How Pigeon Diseases Reach People

The dominant route is not a pigeon pecking your hand or landing on your sandwich. Almost all documented pigeon-to-human infections have occurred through inhalation. Dried pigeon droppings crumble into fine dust that carries bacteria, fungal spores, and viral particles. When that dust becomes airborne and someone breathes it in, infection can follow. One review of cases spanning more than six decades found that aerosol transmission accounted for over 99% of documented pigeon-to-human disease events.² This is why enclosed spaces with heavy droppings accumulation, such as attics, rooftop HVAC units, and warehouse ledges, pose the greatest hazard. A federal workplace health evaluation at a U.S. post office, for example, focused specifically on pigeon droppings fouling rooftop HVAC systems and found the concern was justified, though the actual risk to workers was low after the area was cleaned and netted.³

Direct handling of sick or dead pigeons is the second route, relevant mostly to pigeon fanciers, wildlife rehabilitators, and pest control workers. And a less obvious third pathway involves pigeon ectoparasites, ticks and mites that normally feed on pigeons but can migrate into homes when the birds leave or are removed.

Psittacosis

The infection most consistently linked to pigeons is psittacosis, caused by the bacterium Chlamydophila psittaci. Despite its name (from the Greek for parrot), the disease does not require a parrot. Pigeons are a major reservoir. One urban surveillance study in a European city found C. psittaci in about 21% of pigeon fecal samples, making it the single most common pathogen detected.⁴ A decade-long surveillance program in Madrid detected the organism in pigeons at varying rates across years, though generally at lower prevalence than some other cities.⁵

In people, psittacosis typically starts with high fever, severe headache, a dry cough, and sometimes abdominal pain. It can progress to pneumonia. A case report from Japan described a patient hospitalized with lung infiltrates, headache, and gastrointestinal symptoms who only improved once doctors realized the patient had been caring for a wild pigeon and switched to the right antibiotic.⁶ Another report documented three members of a single family falling ill with pneumonia after exposure to a wild pigeon in their home.⁷

Pigeon fanciers and breeders face the most direct risk. A study that tested 32 pigeon hobbyists found active C. psittaci infection in four of them, confirming that direct zoonotic transfer from homing pigeons to their handlers does occur.⁸ Psittacosis is widely considered underdiagnosed because its symptoms mimic ordinary community-acquired pneumonia, and most doctors do not think to ask about pigeon contact. A population survey in Belgium confirmed this suspicion, finding that psittacosis cases were substantially underestimated and that racing pigeons were a main infection source.⁹

Fungal Diseases From Pigeon Droppings

Two fungal infections stand out in the pigeon disease literature: cryptococcosis and histoplasmosis. Both grow in soil enriched by bird droppings and infect people through inhaled spores rather than through direct bird contact.

Cryptococcus neoformans, the organism behind cryptococcosis, thrives in pigeon guano. Infection can cause pneumonia and, if it spreads, a form of meningitis. A clinical review noted that while cryptococcal lung disease has traditionally been associated with severely immunocompromised patients, it is increasingly recognized in people with intact immune systems, though it remains underdiagnosed because of limited diagnostic tools.¹⁰ For people with weakened immunity, cryptococcosis is one of the most dangerous pigeon-associated threats. One estimate put the risk of acquiring a fungal disease from feral pigeons and their droppings at roughly a thousandfold higher for immunocompromised individuals compared with the general population.²

Histoplasma capsulatum follows a similar pattern. It grows in soil contaminated with bird or bat droppings and enters the lungs as airborne spores. A study in Ecuador, where histoplasmosis is endemic, detected the fungus in about 13% of sampled pigeons and about 21% of bats, and linked these animal reservoirs to ongoing human infections in the region.¹¹ In temperate climates the fungus is less common, but it still turns up wherever pigeon roosts have accumulated heavy droppings deposits over time, particularly in caves, old buildings, and bridges.

Salmonella, Campylobacter, and Other Gut Bacteria

Pigeons carry a range of gastrointestinal bacteria that can cause food poisoning in people, though the transmission route is indirect. Salmonella species show up regularly in urban pigeon surveys. In one Egyptian study, researchers isolated Salmonella Typhimurium and other serotypes from pigeon feces, all of which were multidrug-resistant strains and all of which are known causes of foodborne illness in people.¹² A separate study reported Salmonella prevalence at about 28% in sampled pigeons, alongside E. coli at over 50%.¹³

Campylobacter, the most common bacterial cause of diarrheal illness worldwide, also appears in urban pigeons. A study of feral pigeons captured in public spaces in Montreal found about 9% carried Campylobacter jejuni.¹⁴ The practical concern here is contamination: pigeon droppings landing in food preparation areas, on rooftop rainwater catchment systems, or in ventilation systems create pathways for these bacteria to reach humans indirectly.

Toxoplasma and Parasites

Pigeons can host the parasite Toxoplasma gondii, the organism behind toxoplasmosis. While cats are the definitive host, pigeons serve as intermediate carriers. Across studies, the global prevalence of Toxoplasma in pigeons sits around 7%.¹⁵ Regional rates vary: a survey in northern China found about 11% of pigeons intended for human consumption tested positive, with adult birds more likely to be infected than juveniles. The study authors specifically warned against eating pigeon meat raw or undercooked.¹⁶ An Egyptian investigation confirmed Toxoplasma infection in about 14% of sampled pigeons and flagged them as a public health concern because of soil contamination near pigeon roosts.¹⁷

For most healthy adults, Toxoplasma infection from any source is either asymptomatic or causes mild flu-like symptoms. The serious risks are to pregnant women, where infection can harm the developing fetus, and to immunocompromised individuals, where it can cause life-threatening brain inflammation. In cultures where pigeon meat is a delicacy, thorough cooking eliminates the parasite.

Viral Threats

Viruses are the category where public fear and actual risk are most mismatched. Whenever avian influenza makes headlines, people worry about the pigeons in the park. In reality, pigeons are poor propagators of influenza viruses. A review of studies on avian influenza in pigeons concluded that while pigeons can be experimentally infected, they shed virus in amounts too small to infect other species, making them essentially dead-end hosts.¹⁸ A 2025 experiment with the H5N1 clade currently circulating in poultry confirmed this: pigeons required an enormously high viral dose to become infected at all and transmitted the virus poorly afterward.¹⁹ An Egyptian study did document a natural outbreak of H5N1 in domestic pigeons with 10% mortality and virus shedding from both infected and contact birds, but this appears to be an exception rather than the norm, and occurred with a specific viral lineage in a high-exposure poultry setting.²⁰

The virus that does occasionally jump from pigeons to people is pigeon paramyxovirus 1 (PPMV-1), a variant of Newcastle disease virus. In healthy people, infection typically causes nothing worse than mild conjunctivitis. But rare severe cases have been documented. An immunocompromised two-year-old in Australia died from PPMV-1 neurologic disease, the first known fatal human case.²¹ A separate report described a severe lung infection in a patient with long COVID who had been exposed to a neighbor’s pigeons, suggesting that prior immune compromise from COVID-19 may have made the patient unusually vulnerable.²² These cases are extremely rare but underscore a theme that runs through every pigeon-related disease: immune status matters enormously.

Pigeon Ticks and Mites

Pigeons carry ectoparasites that can become a direct human nuisance if pigeon nests are on or near buildings. The two most relevant species are the red blood mite (Dermanyssus gallinae) and the European pigeon tick (Argas reflexus). The mites are irritating; they cause itchy bites but are generally harmless. The ticks are a different story.²³

After repeated bites from the pigeon tick, some people develop an allergic sensitization that can escalate to anaphylactic shock. In a report from Poland, residents repeatedly bitten by pigeon ticks developed severe inflammatory skin reactions with purple lesions, central necrosis, and lasting scars.²⁴ At least one death from pigeon-tick-induced anaphylaxis has been reported in Europe.²³ The risk is highest when pigeon nests are removed or pigeons are excluded from a roost without simultaneously treating the area for parasites; the hungry ticks then migrate indoors looking for another blood meal.

Bird Fancier’s Lung

Not all pigeon-related illness involves an infectious organism. Bird Fancier’s Lung is a form of hypersensitivity pneumonitis, an inflammatory lung disease triggered by repeated inhalation of proteins shed in pigeon feathers, droppings, and dried serum.²⁵ It is not an infection; it is an immune overreaction. The condition was first described in pigeon breeders in the 1960s, when researchers showed they could reproduce episodes of acute pneumonitis by having patients inhale pigeon feathers or aerosols of pigeon droppings under controlled hospital conditions.²⁶

Symptoms include shortness of breath, cough, fever, and fatigue that develop hours after heavy exposure. Over time, repeated episodes can lead to permanent lung scarring. The condition is thought to be underdiagnosed because patients and physicians may not connect chronic breathlessness with bird exposure, particularly if the exposure is low-level but ongoing, such as living in an apartment building with pigeons nesting on the roof.

Drug-Resistant Bacteria in Pigeon Droppings

A growing concern in the research literature is not just which bacteria pigeons carry, but how resistant those bacteria are to antibiotics. Studies consistently find that pigeons in urban areas harbor multidrug-resistant strains. In one study, over half of Salmonella isolates from pigeons were classified as multidrug-resistant, with complete resistance to tetracycline and near-complete resistance to nalidixic acid.¹³ A study of E. coli from pigeon droppings on rooftop rainwater catchment tanks found about two-thirds of the isolates were antibiotic-resistant, and the pigeon feces were the probable contamination source for the water supply below.²⁷

Urban pigeons in Costa Rica were found to carry antimicrobial resistance genes that could potentially transfer to bacteria in the human environment.²⁸ Pigeons forage in garbage, sewage runoff, and other contaminated environments, picking up resistant organisms and then depositing them across a wide area. They are not the primary driver of antibiotic resistance, but they act as a mobile reservoir that spreads resistant bacteria across the urban landscape.

Who Faces Real Risk

The consistent message across the pigeon disease literature is that healthy adults face low risk from casual urban pigeon contact. A study of feral pigeons in Costa Rica summed it up plainly: these pigeon populations pose limited risk to healthy adults but may present a genuine health threat to immunocompromised people and young children.²⁹ The severe and fatal cases documented in the medical literature overwhelmingly involve people with immune deficits. The fatal PPMV-1 case in Australia involved an immunocompromised child.²¹ The thousandfold elevated risk for fungal disease applies specifically to immunocompromised individuals.²

This does not mean everyone else should be careless. People who work with pigeons professionally or as hobbyists accumulate exposure over time, and psittacosis and Bird Fancier’s Lung are occupational hazards for this group. Anyone cleaning out heavy pigeon droppings deposits should wear respiratory protection and dampen the material before disturbing it to avoid aerosolizing pathogens and fungal spores. And people who collect rainwater from rooftops where pigeons roost should be aware that the water may carry resistant gut bacteria from pigeon droppings.

Pigeon Meat and Foodborne Risk

In many parts of the world, pigeon (squab) is a regular menu item. The primary foodborne concern is Toxoplasma, as noted earlier, along with Salmonella. A survey of pigeons sold for human consumption in northern China found that roughly one in nine carried Toxoplasma antibodies, and older birds were significantly more likely to be positive than young ones.¹⁶ The practical takeaway is straightforward: cook pigeon meat thoroughly. Both Toxoplasma cysts and Salmonella bacteria are killed by standard cooking temperatures. The risk exists primarily in culinary traditions that involve raw or lightly cooked preparations.

Feral urban pigeons, as opposed to farm-raised squab, carry a broader load of resistant bacteria and environmental pathogens due to their diet and habitat. Eating feral birds that have not been inspected or tested adds an additional layer of uncertainty that farmed birds do not carry.