By Iván Paredes, Mongabay; El País:

Domestic Cats Are Spreading a Deadly Disease to Bolivia’s Wild Cats

Feline panleukopenia, a highly contagious virus that can kill young cats, is emerging as a new threat to wildlife as domestic animals increasingly encroach on natural habitats

Geoffroy’s cat

Gato Montés

Gato Montés

Gato Montés

A disease commonly associated with household cats is becoming a concern for wildlife conservation in Bolivia, where increasing contact between domestic animals and wild felines is creating new opportunities for infection.

Feline panleukopenia is caused by a highly resistant virus that spreads through infected bodily fluids and contaminated surfaces. It does not infect people or dogs, but it can be deadly to cats, particularly young animals.

Conservationists are now warning that unvaccinated domestic cats may be transmitting the disease to wild felines, including the Geoffroy’s cat (Leopardus geoffroyi), known locally as gato montés.

One case illustrates the risk.

In 2023, a young wild cat was taken from its den in Cochabamba and brought into an urban home as a potential pet. During the four weeks it spent outside its natural habitat, it contracted feline panleukopenia, likely after coming into contact with domestic cats.

The animal was eventually transferred to the Senda Verde wildlife refuge in La Paz. It was already severely malnourished, and the infection had progressed too far. Despite veterinary treatment, it died.

For conservation specialists, the case highlights a broader problem: the boundaries between domestic animals and wildlife are becoming increasingly blurred.

“Wild animals are being exposed to pathogens against which they have no defenses,” said Paola Nogales, coordinator of the Bolivian Feline Research Program, or PIF Bolivia.

The risk is particularly high in rural areas, where domestic cats and dogs can move freely between settlements, farms and natural ecosystems.

A disease moving across the wildlife boundary

Enzo Aliaga-Rossel, a researcher at the Institute of Ecology of the Universidad Mayor de San Andrés and a member of PIF Bolivia, describes the phenomenon as a “zoonotic spillover” linked to growing interaction between domestic animals and wildlife as ecosystems are altered.

The problem is difficult to measure.

There is significant underreporting of diseases among Bolivia’s wild felines, researchers say. Monitoring populations in remote areas requires specialized equipment, funding and permits, while sick or dead wild animals may never be examined by veterinarians.

That leaves researchers with only a partial picture of how widely the virus may already have spread.

For the Geoffroy’s cat, the disease adds another pressure to a species already facing human-driven threats.

The species occurs across several regions of Bolivia, including the southern Andes, the Chaco, the Chiquitania and the inter-Andean valleys. Its range also extends through Argentina, Paraguay, Brazil, Uruguay and Chile.

Globally, the International Union for Conservation of Nature classifies the species as Least Concern. In Bolivia, however, it is considered Near Threatened.

Illegal wildlife trafficking, hunting, roadkill and habitat loss are among its established threats. Disease transmitted by domestic animals could now add another.

Vaccinating pets could protect wildlife

Researchers say one of the simplest ways to reduce that risk is also one of the most overlooked: vaccinating domestic cats.

The feline combination vaccine protects against panleukopenia, but vaccination coverage remains limited in many rural parts of Bolivia, where veterinary services and public vaccination campaigns are scarce.

Veterinarian Freddy Verástegui says the virus attacks white blood cells and tissues where cells reproduce rapidly. The resulting disease can cause severe illness and high mortality, particularly in kittens.

Nogales says rural communities also need access to free vaccination and sterilization programs.

The lack of veterinary care in these areas, she says, is often not a matter of neglect by pet owners. Many families simply cannot afford veterinary services, while clinics and public programs may be far away or unavailable.

Keeping domestic animals healthy, researchers argue, is therefore also a conservation measure.

“Every protected domestic cat is a life saved in the wild,” Nogales said.

Wild cats are not pets

The death of the young cat at Senda Verde also illustrates another danger: removing wild kittens from their habitat.

Vicky Ossio, director of the refuge, said the animal had been separated from its natural environment for weeks before arriving at the center.

A kitten found alone in a forest is not necessarily abandoned. In most cases, its mother may simply be nearby searching for food.

Taking the animal home can interfere with its development and expose it to domestic pathogens that it would not normally encounter.

The researchers say the same principle applies to dogs and cats allowed to roam freely through forests and other natural areas. Their movement increases the number of opportunities for pathogens to pass between domestic and wild populations.

Why Tarija should pay attention

No cases of feline panleukopenia have so far been documented in wild cats in Tarija. But the department contains Chaco and valley ecosystems inhabited by the species, making prevention important even in the absence of confirmed infections.

Conservation specialists recommend keeping domestic cats and dogs vaccinated, preventing them from roaming freely near forests and never taking wild feline kittens home.

Anyone who encounters a sick or injured wild animal should avoid handling it and notify environmental authorities. Municipal Zoonosis services and organizations involved in wildlife and environmental management can assist with the response.

For Bolivia’s wild cats, conservation may increasingly depend not only on protecting forests and stopping illegal hunting, but also on controlling what domestic animals carry into those forests.