When Birgitte Kallestad and her friends saw a helpless puppy on the side of the road while traveling in the Philippines last February, they couldn’t help but pick it up and take it back to their resort. Kallestad washed it and played with it, her family later said, falling in love with the small creature, even when it started to bite her.

For Kallestad, saving the puppy proved fatal.

The 24-year-old died on Monday in her native Norway after contracting the rabies virus, the Verdens Gang tabloid reports.

Rabies is a virus that can be transmitted from animals to humans via bites and saliva, and it can prove fatal if not treated early. According to the World Health Organization, 99 percent of rabies infections in humans are caused by dog bites.

In a statement given to NRK, government-owned media in Norway, Kallestad’s family explained that she had been back in Norway for a long time before she fell ill. Doctors struggled to solve the mystery of what was wrong. She made several trips to the emergency room and was eventually admitted to a hospital on April 28.

It wasn’t until Thursday when doctors finally figured out she may have rabies, after learning she had been bitten on vacation, Verdens Gang reported.

“The patient was admitted to our intensive care unit, and died peacefully with the closest family around her,” Trine Hunskar Vingsnes, director of health at Helse Forde hospital, told VG.

Norwegian officials say this is the first case of rabies reported in Norway in 200 years.

“Our dear Birgitte loved animals. Our fear is that this will happen to others who have a warm heart like her,” the family statement said. They called for a rabies vaccine to be added to a list of inoculations for people traveling to the Philippines.

WHO lists the Philippines as a high-risk country for humans contracting rabies. More than 59,000 people worldwide die each year of the disease, which is preventable with a vaccine. But impoverished or disadvantaged communities with limited access to health care remain vulnerable to contracting rabies through dogs, an issue the WHO hopes to eliminate by 2030.

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