On a recent, gloomy winter night at the Painted Dog Conservancy in Zimbabwe’s Hwange National Park, Rocket, the matriarch of one of the strongest packs of African wild dogs in the country, succumbed to rabies; she was the last of her kin to do so, after the preventable disease killed her family earlier in the week. Rabies, while fairly common in domestic dogs throughout Asia and Africa, can take out entire wild populations of African Cape or “painted” dogs—a prospect many biologists and environmentalists hope to avoid. Painted dogs are listed as endangered, and current population numbers hover around 5,000 individuals. Any loss, let alone an entire pack of healthy adults and juveniles, is a major blow to the wild dog’s survival on the planet.

Painted dogs are some of the most successful hunters on Earth. They hunt cooperatively in packs, better than lions or spotted hyenas—a rare occurrence for large predators (about 80 to 95 percent of the world’s carnivores hunt alone). Also, like other canids, they regurgitate food for their young, but painted dogs will extend this courtesy to adults as well.

Like North American gray wolves, painted dogs avoid human interaction in general except when one becomes rabid. In some cases it may lose its sense of fear and approach human settlements. But after the pack in Zimbabwe died, the alarm started to go off for Peter Blinson, the executive director of the Painted Dog Conservancy.

“Initially we saw severe bite marks on the face of the alpha male, and three pups were missing,” he said. “At that stage we thought that it was probably a confrontation with hyenas."

Painted dogs typically contract rabies from other predators, such as hyenas, according to Sarah Cleaveland, professor of comparative epidemiology at the University of Glasgow. She directs rabies-prevention programs in Tanzania and South Africa. But the “chain of transmission” could include a number of species, mostly carnivores, such as jackals and foxes, too.

After a dog becomes infected, the virus travels to the brain and renders the animal hyper-aggressive and excitable, with a hoarse howl, according to the World Health Organization. The virus spreads to the salivary glands, which start producing saliva laden with billions of viral copies. It also makes it hard for the dog to swallow, leading to more saliva and increased chances of transmission.

A few days after the pups went missing, Blinston and his team found one of the adult members of the pack acting strange.

“At this stage we were really concerned and rather confused,” he said. “We received a report that [a painted dog] was ‘hanging around’ a nearby safari camp. This camp happened to have German shepherd pups. We concluded that his behavior was very typical of a rabid dog. He was showing no fear of humans or indeed the German shepherds. This is when we reported to the authorities that we may be dealing with rabies.”

The conservancy darted the remaining four adults in quick succession and quarantined them. A few started to show the signs of rabies and were euthanized, while others, including Rocket, died naturally. All tested positive for rabies. It’s a gruesome business to test for rabies exposure after death. Blood work can produce inaccurate results, so the only surefire way to know if a dog, or a human, has been exposed to rabies is to check in the brain.

Rabies isn’t a concern for most people in North America and Europe, but in Africa and Asia the virus kills an estimated 59,000 people each year. Domestic dogs cause the infection in most rabies cases. Some patients have convulsions and become aggressive, just like rabid dogs. Because many victims are children, the World Health Organization and other groups announced a goal to eliminate rabies deaths worldwide by 2030.

But the question remains in conservation circles if wild painted dogs and other wildlife should be vaccinated against rabies. Blinston says that the IUCN Canid Specialist Group, an international organizational body of experts, recommended against vaccinating the painted dogs in Zimbabwe. “The vaccines are developed on domestic dogs, and tests in zoos on painted dogs have apparently been inconclusive,” Blinston said. “As repeated vaccination is recommended (for domestic dogs) it is considered too invasive to be vaccinating painted dogs in the wild every year.”

In September 2017, approximately 1,300 domestic dogs were vaccinated in the area surrounding Hwange. The yearly program brought in veterinarians from Wildlife Vets International, and surveys are conducted on a regular basis to give accurate population numbers on domestic dogs in the area. The program vaccinates domestic dogs every year.

For Cleaveland, keeping domestic dogs vaccinated is a monumental task. If enough of the population is protected, epidemics cannot take hold. “It is a difficult effort, but it needs to be sustained,” she said. “What we need to do to eliminate rabies entirely is to extend the vaccination areas.”

Cleaveland believes that painted dogs should be included in the vaccination programs. She says that it isn’t necessarily more difficult to vaccinate African wild dogs than domestic dogs. They can either be trapped and injected with a booster or darted with a vaccine. She noted that a lot of misinformation for arguments against vaccinating wild dogs has created hesitancy by government officials to extend rabies prevention campaigns to wild dog populations.

One example she gave detailed an incident in the 1990s when a group of wild dogs were vaccinated for rabies but several months later they all died—showing symptoms similar to rabies. (It was more likely to be distemper, according to Cleaveland, but somehow it was believed that the vaccine was the cause of the dogs’ death.) “The vaccine is entirely safe,” she said. “It’s frustrating to hear misleading information being spread.”

Cleaveland agrees that not every wild dog needs to be vaccinated, and that it should be on a case-by-case basis. “Vaccination can play a really important role,” Cleaveland said of the painted dog’s survival. “I think it should be considered as an option. I hope in 20 years we won’t have to talk about it.”