The Zika epidemic flaring across the Americas has produced several hot spots with large numbers of cases. But there is no place quite like Turbo.

The mosquito-borne virus has spread rapidly here and across lowland Colombia, but the city is unusual for the subsequent outbreak of a rare, debilitating disorder known as Guillain-Barre syndrome, whose precise link to the virus remains unclear. Before Zika's arrival in Turbo, a mostly Afro-Colombian town of 60,000 set amid vast banana plantations on the country's north coast, doctors typically saw one case of Guillain-Barre a year, if that.

In the past six weeks, there have been five, all of them severe. Three patients have died. One is fighting for his life in an intensive care unit. The fifth, a 10-year-old girl, hasn't been able to move her legs in a week.

The deaths, and the aggressiveness of the Guillain-Barre cases here, are among the first signs of a strange and worrisome pattern that is challenging the way doctors in Colombia and across Latin America are preparing for the spread of Zika.

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Much of the global attention to the virus has zeroed in on a suspected link to microcephaly, a congenital defect that leaves babies with undersized heads and varying degrees of nerve damage. Brazilian officials say they may have hundreds or thousands of such cases related to Zika. But the photos of worried mothers and distressed infants may have given many people the impression that the virus poses no major risk to anyone else.

That is not true, and certainly not here in Turbo, where rank, sewage-filled canals line the streets and more and more people are arriving at the crowded emergency room with bloodshot eyes and itchy, red pockmarks, the telltale signs of Zika. Something about the virus - and researchers still don't know what it is - appears to significantly increase the incidence of Guillain-Barre.

The first resident here to get it was 41-year-old Eliana Uribe. She called in sick to her cousin's dress shop one morning in mid-January, not long after missing several days of work with a strange rash and sore joints. Something was wrong with her feet, she said.

A few hours later, when Uribe tried to walk, she collapsed. Her legs felt "like rags." The illness was creeping toward her torso.

Uribe's family carried her to the emergency room. German Gomez, the internist at the small public hospital, thought it might be Guillain-Barre. But he wasn't sure.

"I'd been here 15 months and hadn't seen a single case," he said.

Two days later, Uribe lost control of her tongue and facial muscles. She fell short of breath. Doctors rushed her to a bigger hospital.

Uribe died Feb. 2, her brain swamped in fluid - "severe hydrocephaly," doctors told her family. "They never told us you could die from it," said Katarina Lemus, Uribe's cousin.

The disease has made an orphan of Uribe's 12-year-old son, Marlon, whose father died of a heart attack last year. "Whenever anyone asks about his mother, he just crumples," said Shirley Uribe, his aunt.

The day after Uribe's death, another Turbo resident, Edelberto Padilla, 51, also died with Guillain-Barre, at a different hospital. He had the symptoms of Zika, too.

The Colombian government has confirmed three fatalities with Guillain-Barre, including two of the Turbo patients, blaming the deaths on Zika.

The U.S. Centers for Disease Control and Prevention (CDC) has confirmed two cases of Guillain-Barre related to Zika in the continental United States, presumably among the more than 80 travelers infected by the virus who have returned to the country. Another Guillain-Barre case was reported in Puerto Rico.


Immune systems go haywire

The normal prevalence rate for Guillain-Barre is one or two cases per 100,000 people, said Kenneth Gorson, a professor of neurology at Tufts University in Boston, who is one of the leading U.S. authorities on the disorder, named for the two French neurologists who discovered it exactly 100 years ago.

At its most basic level, Guillain-Barre occurs when a patient's immune system fights off an infection and then goes haywire, as antibodies turn against the body's nervous system, Gorson said. They attack nerve cells, apparently mistaking them for a virus. In some instances, the antibodies strip away the membrane that protects nerve endings, called myelin, leaving the body's muscles essentially unable to communicate with the brain.

In his courses, Gorson tells students that Guillain-Barre itself isn't fatal. "What kills people is being paralyzed in an intensive care unit," he said. "It's the complications from being on a ventilator for long periods of time, the risk of blood clots, wound infections from lack of movement or other numerous medical complications that occur in paralyzed patients. Access to quality care is critical."

Adults and children appear to be equally at risk of developing Guillain-Barre, but patients who already have health problems or compromised immune systems are less able to recover from it.

One Guillain-Barre study in the Netherlands found a death rate of 1 in 20, "but that is with high-level care," Gorson said. About one-quarter of patients need breathing assistance.

Belarmina Ayarza, 58, contracted Zika while visiting her family in Turbo in January, then checked into a hospital in the city of Medellin 10 days later when she lost feeling in her legs. Doctors diagnosed Guillain-Barre, said her son, Jose Barrios.

Ayarza was a diabetic, with high blood pressure. But her condition stabilized, and Barrios was able to take her home in a wheelchair. On Feb. 7 she started convulsing in her bed. "I picked her up and held her in my arms," Barrios said, "but she was gone." Doctors said she'd had a heart attack.


Lack of high-level care

In the rural areas of Latin America where Zika is spreading, high-level care is often unavailable. Wait times at public hospitals, especially those swamped by Zika patients, can discourage patients from seeking care. Those with aggressive Guillain-Barre need complicated blood transfusions or a treatment known as immunoglobulin therapy to essentially wash out the harmful antibodies. But the treatments can cost more than $10,000, and patients may need several rounds.

Colombia says that more than 30,000 citizens have been diagnosed with Zika so far, with 97 cases linked to Guillain-Barre. Brazil, Venezuela, El Salvador and Suriname have also reported a surge in the disorder. The same pattern appeared during the Zika outbreak in French Polynesia in 2013 and 2014, when at least 42 patients, most of whom were diagnosed with Zika, developed Guillain-Barre.

"We are seeing a spike everywhere that we are seeing the Zika virus," said Tarun Dua, a neurologist at the World Health Organization (WHO).

What's unclear is whether Zika is causing Guillain-Barre or whether it is"cross-reacting" with antibodies from other widespread mosquito-borne viruses such as dengue or chikungunya.

Another major problem: There is no widely available, quick test for Zika, and the virus remains in an infected patient's blood only for about a week. So it's difficult to test for Zika in patients hospitalized with Guillain-Barre symptoms.

"The hypothesis is that Zika may be a more efficient trigger of Guillain-Barre, but we can't say that at the moment," said Anthony Costello, director of maternal, child and adolescent development at WHO. "The detective work is starting, but it takes time."

In Turbo, patients diagnosed with Zika - whose symptoms include rash, joint pain, headaches and bloodshot eyes - are typically given acetaminophen and sent home to rest.

But they may share their homes with the Aedes aegypti mosquitoes that pick up the disease from infected people and spread it. They breed in stagnant water.

In a squalid neighborhood at the edge of a town known as El Bosque, the streets are unpaved and motorbikes weave around chickens and children playing in the streets. Occasionally a truck rumbles through blaring advertisements on giant speakers, with an occasional public-health message urging residents to dump out standing water.


There are no health inspectors or fumigation crews to be seen. A foul, black bisque of sewage and trash oozes through a canal right in front of the home of Wilfrido Molinares. Children and horses walk through the muck; a frayed sofa sits half-submerged, rotting.

Molinares's daughter Paula, 10, has been hospitalized with Guillain-Barre for nearly two weeks in the nearby city of Monteria. She had Zika symptoms before that. He's had Zika, too, and was laid up from his construction job for two months last summer with chikungunya, which causes fevers and joint and muscle pain. Zika seemed mild compared with that, he said, until his daughter couldn't stand on her own.

In their neighborhood, everyone stores drinking water in tanks, jugs and empty bottles.

"There are a lot of mosquitoes here," Molinares said. "I bought mosquito repellent and spray it all over. But when the sun goes down, sometimes you can't even sit outside."