"The word 'syndrome' was overwhelming because to me, it means 'for life,' " she says
Even after contracting a life-altering syndrome from a feral cat she befriended on vacation, Gemma Birch still considers herself an animal lover.
The 25-year-old from Southport, England, was spending a week in Albufeira, Portugal, in June 2015 when she took in a “gorgeous” stray cat who would lounge on the patio of the rental apartment, Birch recalls to PEOPLE.
Immediately smitten, Birch began giving the animal milk from a bowl and letting her inside.
“She obviously loved me, and she’d follow me everywhere,” says Birch, who runs a lifestyle blog and works in a gym. “I was fine all week. I was so sad to leave her.”
But on the last night, she started vomiting severely and suffering from diarrhea. On the plane ride home, on top of her existing symptoms, Birch started to feel faint.
By the time she landed, her stomach was so swollen she looked “nine months pregnant,” she says. “Like I was about to burst.”
She made it home, where her father immediately told her she needed to go to the hospital because she was so weak and pale, Birch recalls.
After spending a week in the ICU and undergoing many tests, doctors discovered Birch had been infected with campylobacter, a common cause of food poisoning.
Doctors asked if she’d eaten any uncooked poultry. A staunch vegetarian, Birch said no. Then they asked if she had come into contact with any animals recently, and she remembered her feline friend.
Next came more tests, which helped the medical team discover that she had contracted the infection from a living animal.
“Once they found out, they weren’t worried. They said I’d get better at home with bedrest,” Birch recalls. “But I got worse. I couldn’t walk. I kept falling and losing my balance.”
Her symptoms, inconsistent food poisoning, led Birch to make repeated appointments with her general practitioner, who kept telling her to just get more rest.
“Eventually I stopped going because I felt like I was bugging them,” Birch says. “But you just know when it’s something else.”
Then, two weeks after leaving the hospital — three weeks after returning from Portugal — Birch woke up around 3 a.m. because she’d fallen out of bed.
“I couldn’t feel my legs on the sheets or my feet on the carpet,” she explains. “I started scratching my legs so hard that they bled, but I still couldn’t feel it. I screamed for my dad, and he took me to the hospital.”
In the emergency room, Birch says she googled her symptoms and the campylobacter bacteria, which turned up three words: Guillain-Barré syndrome. GBS is a neurological disorder in which the body’s immune system mistakenly attacks its nervous system, according to the NIH.
When she showed her research to the doctor, he told her GBS was rare, Birch says, but agreed to run tests. When she woke the next morning, her symptoms were considerably worse.
“The night before, I could still move my legs a little bit, but the next morning, I couldn’t move them at all. My arms were really weak and I needed help breathing,” Birch says. She was temporarily paralyzed, a common symptom of GBS.
That day she received her official diagnosis, and for the next month she stayed in the hospital receiving immunoglobulin treatments, which added antibodies to her system. Then she was transferred to a hospital with neurology experts in Liverpool, where she stayed for another month before she moved to a rehab center. For four months, she tried to combat her paralysis from the neck down.
“I didn’t want to go [to the rehab center] because it was far from home, but it was the best decision I could’ve made,” Birch recalls. “I remember a nurse asked me what my goal was, and I told her it was to dance at New Year’s Eve on my own.”
At the time, the summer was coming to a close, so the nurse asked her to pick a “more realistic goal.” But, Birch says, “I did it. I danced at New Year’s Eve  with crutches.”
It took her a year to learn how to do basic physical tasks again, like “walking, writing and picking up a mug.” And all the while, she was taking university classes because she wanted to graduate on time alongside her twin sister.
“I just thought, GBS has taken everything from me, but it’s not going to take away my degree,” she says.
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These days Birch is able to work, drive and maintain her lifestyle blog, Sorsasta. But GBS symptoms often pop up, for example after exercising too much. She starts to get tremors so severe she’s been unable to drive herself home from the gym.
And since GBS affects the immune system, she gets sick more easily than before. There have been four times since she left rehab that a cold has landed her in crutches.
Looking back, Birch recalls one of the scariest things about her experience was learning the name of the condition.
“The word ‘syndrome’ was overwhelming because, to me, it means ‘for life,’ ” she says, adding that it’s incredibly rare to contract GBS from touching a live animal. Uncooked poultry is a more common source.
According to WebMD, GBS is most common in people older than 50 — Birch recalls meeting two older women suffering from it in the rehab center — but it can strike at any time. It’s also unclear exactly how the disease progresses. Some cases have originated from Zika virus while others start from germs, like Birch’s.