JOIN USIn Brazil, Zika virus linked to surge in rare condition
A mosquito-borne virus that has been linked to severe brain damage in infants may be causing another serious health crisis as well, Brazilian officials and doctors warn: hundreds of cases of a rare syndrome in which patients can be almost completely paralysed for weeks.
The virus, called Zika, made its way to Brazil recently but is spreading rapidly around Latin America and the Caribbean. Nearly 4,000 cases of brain damage called microcephaly, in which babies were born with unusually small heads, have been registered in Brazil in the past year. This month US officials warned pregnant women to delay travelling to any of nearly 20 countries in the Western Hemisphere, as well as Puerto Rico, where mosquitoes are spreading the virus.
But disease specialists in Brazil say that the virus may also be causing a surge in another rare condition, the potentially life-threatening Guillain-Barré syndrome, in which a person’s immune system attacks part of the nervous system, leaving some patients unable to move and dependent on life support.
Until recently, the condition was so rare that Brazil’s Health Ministry did not require regional officials to report it. But last year, the authorities in northeast Brazil, the part of the country hit hardest by the Zika virus, counted hundreds of cases of Guillain-Barré, prompting doctors to sound the alarm.
“Guillain-Barré can be a nightmare for those who have it,” said Dr Wellington Galvão, a haematologist in the city of Maceió in northeast Brazil who treated 43 patients with Guillain-Barré in 2015, up from an average of 10 to 15 cases in previous years. “I estimate that Zika increases by about 20 times the probability that an individual can get Guillain-Barré.”
Shortly after a mosquito infected Patricia Brito with the Zika virus, she knew something was terribly wrong. Soon she could not move her legs. The paralysis soon spread to her arms, her face and the rest of her body, to the point that doctors put her on a ventilator in an intensive care unit for 40 days.
“It was more terrifying than any horror movie,” said Brito, 20, who works as a cashier at a bakery in Delmiro Gouveia, a city in northeast Brazil. Months after her release from the hospital, Brito still does physical therapy in an effort to avoid using a wheelchair.
Researchers caution that more studies are needed to prove the link between Zika and Guillain-Barré. A spokesman for the Centres for Disease Control and Prevention in the United States said that “reports must be treated as anecdotal because little pertinent supporting diagnostic information is available.”
Still, the CDC is viewing Guillain-Barré as a serious risk. It is helping Brazil conduct a study this month to evaluate if any link exists between the condition and the Zika virus.
Last week, the CDC confirmed the presence of the Zika virus in a baby born with an unusually small head and brain in Hawaii — the first case of brain damage linked to the virus in the US. (The mother had been in Brazil while she was pregnant). But the CDC added that it had not found an increase in Guillain-Barré cases in any US territory, including Puerto Rico.
Camila Bogaz, a spokeswoman for Brazil’s Health Ministry, cited a recent study by the Federal University of Pernambuco showing that some patients with Guillain-Barré syndrome had previously been infected with Zika. But she, too, cautioned that the connection between Zika and Guillain-Barré was still under investigation.
Outside Brazil, other countries around Latin America where Zika is spreading are reporting an increase in cases of Guillain-Barré, including Colombia and Venezuela. This month, El Salvador said it was seeing a surge in Guillain-Barré cases. It normally averages about 14 per month, but between December 1 and January 6, it recorded 46, two of them fatal.
Of the 22 patients for whom medical histories were available, about half remembered having had the fever and rash that are the most common symptoms of Zika, between a week and two weeks before their paralysis began.
Most people with Guillain-Barré recover, but their struggle is often harrowing. Patients in Brazil described a creeping inability in their limbs to feel textures, heat and pain, along with sensations of tingling in parts of their body. In severe cases, they can become almost completely paralysed — conscious but unable to speak or move, as if trapped inside their bodies — and can go into cardiac arrest or comas.
“It felt like I was drowning in a sea of mud,” said Geraldo da Silva, 43, a construction worker in the town of Murici in northeast Brazil who was hospitalised for 10 days in an intensive care unit after doctors discovered he had Guillain-Barré. “I became motionless and thought I would die. All of this happened just a few days after I had Zika.”
Result of viral infections
Guillain-Barré has sporadically been diagnosed as a consequence of a number of viral infections, including other mosquito-borne diseases like dengue fever, chikungunya and West Nile virus.
“The increase in Guillain-Barré is very similar to what happened when dengue spread rapidly here in 2003 and 2004,” said Dr Maria Lúcia Brito, a neurologist in Recife in northeast Brazil who treated 50 patients with Guillain-Barré in 2015. “This makes mosquito eradication campaigns even more urgent across Brazil.”
Patients with Guillain-Barré are often treated by removing blood from the body, separating it, returning the red and white blood cells, and discarding the plasma. Scientists are not sure why it helps Guillain-Barré patients, but they think it may be because it removes antibodies made by the patient that are attacking the patient’s nerves in an autoimmune reaction.
Guillain-Barré typically occurs a few days or weeks after someone has had symptoms of a respiratory or gastrointestinal viral infection, according to the National Institute of Neurological Disorders and Stroke in the US.
Almost every country has some cases of Guillain-Barré every year; it strikes about 1 person out of 100,000. Although its cause is unknown, it sometimes follows bouts of flu, bacterial infections, surgery or even vaccinations.
Before the arrival of the Zika virus in Brazil, another strain of the virus began island-hopping across the South Pacific in 2007. Small but intense epidemics erupted each time it hit a new island where residents had no immunity to the virus. During an outbreak that began in 2013 in French Polynesia, which includes Tahiti and more than 30 other islands, scientists noticed that cases of Guillain-Barré syndrome soared.
Researchers are still not sure how the Zika virus made its way to Brazil. Some say it could have arrived during the World Cup in 2014, when Brazil welcomed players, fans and others from around the world. Others think the virus may have come during a canoe race weeks later, when paddlers from French Polynesia arrived in Rio de Janeiro.