Two women tell Healthline about the devastating effects of a disease now connected to the Zika virus.

Kim Earnshaw was 18 years old when she woke one morning and noticed she couldn’t feel the tips of her middle fingers.

The next day her feet felt funny.

The day after, she told her parents about the lack of sensation in her hands and feet and saw a doctor.

The doctor chalked it up to a protein deficiency and sent her home, but by the next morning the numbness had traveled.

“I couldn’t feel my feet,” Earnshaw told Healthline. “I put my feet down on the hardwood floor and it hurt.”

Earnshaw ignored the numbness. She went to her job at a seafood counter in a local grocery store.

That night she was doing inventory at the counter. She had to weigh 20-pound boxes of seafood and log the information into a spreadsheet. Within 20 minutes Earnshaw could no longer lift the boxes or even read the numbers on the spreadsheet.

Scared, she sprinted to the front of the store.

“I was running down the aisle and kept falling and falling,” she said.

That evening Earnshaw was diagnosed with Guillain-Barré syndrome (GBS). Her paralysis lasted almost two months.

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GBS is an autoimmune disorder that attacks the body’s peripheral nervous system and causes paralysis, according to the National Institute of Neurological Disorders and Stroke.

Symptoms usually start at the feet and work their way up the body. GBS can also affect organs, forcing some patients to receive a tracheotomy to breathe.

It’s estimated that roughly one in 100,000 people will develop GBS.

While researchers are unclear why some people develop the disorder, they agree it’s triggered by a bacterial or viral infection.

“There is definitely tight epidemiology between campylobacter bacteria and Guillain-Barré syndrome,” said Dr. Michael Wilson, assistant professor of neurology at the University of California San Francisco (UCSF) School of Medicine.

More recently the Centers for Disease Control and Prevention (CDC) declared that there is a correlation between GBS and the Zika virus.

A number of Latin American countries have reported high rates of GBS during the Zika outbreak. Brazilian cases of GBS jumped 19 percent between 2014 and 2015. El Salvador saw 104 cases of GBS in one month during a Zika outbreak last year, compared to a yearly average of about 170 cases.

French Polynesia had a Zika outbreak from October 2013 to April 2014 and saw roughly 40 cases of GBS during that same time. Plotted on a chart, Wilson said the timeline reveals an increase in GBS as Zika starts to wind down. The lag time is considered textbook when looking at how outbreaks manifest, he noted.

There are two hypotheses around the connections between the virus and GBS, according to Wilson. Either Zika has caused GBS for decades and people didn’t notice, or the virus has mutated.

“The jury is still out,” he said.

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Regardless of how someone gets GBS, the onset of symptoms is swift.

Earnshaw was completely paralyzed within 10 days.

For Cindy Conklin Hughes, her paralysis caused by GBS came on in about half that time.

Conklin Hughes was almost 21 years old when she noticed something was off while driving home from a new job. She couldn’t feel the brake pedals. The next morning her legs felt weak and her breakfast tasted like tinfoil.

Just seven days from that initial onset, Conklin Hughes found herself at UCSF Benioff Children’s Hospital where she’d received a tracheotomy to help her breath.

“I couldn’t talk, I had double vision,” Conklin Hughes told Healthline. “No function, no control. I needed diapers. It was horrific, and it was like that for a month.”

Since developing GBS nearly 30 years ago both women have gone on to live normal lives.

Today, Conklin Hughes, 50, is married with three children. Earnshaw, 48, is also married, and has two children.

Still, the memories surrounding their bouts with GBS remain vivid. Both can recall in great detail what it was like to be paralyzed.

“People would tell me to close my eyes and would be poking me and I couldn’t really feel it,” Hughes said. “But then they would rub me and it would hurt so bad.”

Earnshaw said it was almost like an out-of-body experience.

“It felt like I didn’t know where my extremities were,” she said. “I’d get these pains, but I didn’t know where they were coming from.”

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Hughes said her doctors never pinpointed how she developed GBS.

Earnshaw’s doctors suspected she was exposed to the campylobacter bacteria because of her job. The meat department in the grocery store was right next to the seafood counter, so that theory made sense.

While the cause of GBS is unclear, scientists do know what happens in the body when it occurs.

The body’s immune system starts to destroy the myelin sheaths that surround peripheral nerves. These nerves control body function and when the sheaths are damaged nerves can’t communicate with the brain.

“So the damage from Guillain-Barré can be motor problems, sensory problems, or both,” said Dr. Carlos A. Pardo-Villamizar, an associate professor of neurology and pathology at Johns Hopkins University.

There are two types of treatments to combat GBS. The most common today is intravenous immunoglobulin treatment (IVIG). Patients receive an infusion of immunoglobulin extracted from the plasma of donated blood.

The other treatment is plasmapheresis. Also called plasma exchange, the process is similar to dialysis. A person’s blood is withdrawn, the “bad” plasma is replaced with “good” plasma, and then the blood is pumped back into the patient.

Earnshaw and Hughes both went through plasmapheresis, which they say was extremely painful and took hours at a time to complete. However, they credit the treatment with their recovery.

“All of a sudden, I could move my hands,” Earnshaw said.

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The recovery, though, was short-lived. Both women experienced setbacks.

Conklin Hughes had transferred to a rehabilitation center, only to be sent back to the UCSF children’s medical facility. The move back to the hospital was devastating.

“You just question why, why, why,” Conklin Hughes said. “You ask yourself, ‘Am I ever going to walk again?’”

Earnshaw said she started to feel hopeless when it became clear that her recovery had plateaued.

“I panicked and freaked out,” she said, tearing up as she remembered the experience. “I was so upset and crying. I didn’t think I was going to make it.”

After another set of plasmapheresis treatments both women found themselves in recovery and for good this time. The numbness eventually disappeared.

Soon Earnshaw could sit up by herself. Conklin Hughes didn’t need a machine to help her breath. They still both had muscle weakness and needed wheelchairs and walkers.

Conklin Hughes entered rehab again to get her strength back. It took a year before she felt like her old self.

“I had to learn everything all over again,” she said. “Walking, talking, fine motor skills, everything.”

Earnshaw ended up rehabbing at home because of an employee strike at the center she was supposed to enter. She said it took about four months to recover.

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The difference in recovery time between the two women is common, Pardo-Villamizar said. That’s because IVIG and plasmapheresis treatments don’t technically “cure” patients with GBS.

“They help to control the response [of the disorder], but it’s not going to help in the remylination of peripheral nerves,” he said. “That result is [done] by the patient’s own body.”

Most people with GBS make a full recovery. Just 5 percent of patients see a recurrence.

In general, the long-term effects are mild. Earnshaw’s fingers get numb when exposed to snow or icy conditions, and Conklin Hughes’ feet get numb in a matter of minutes when exposed to cold.

Aside from the physical issues, both women said GBS took an emotional toll. Still, Conklin Hughes was determined to fight GBS and walk again.

“I never once gave up,” she said.

Earnshaw said once she recovered, she didn’t look back on her experience for years, but today is retrospective about what she went through.

“Once I was done with it, I was done,” she said. “I wanted to live life to the fullest.”