A neurological disorder which can cause temporary paralysis is on the rise in several Latin American countries that are also seeing an outbreak of the Zika virus, the World Health Organization (WHO) said on Saturday.

The rare Guillain-Barre syndrome (GBS) has been reported in Brazil, Colombia, El Salvador, Suriname and Venezuela, the WHO said in a weekly report on Zika virus now circulating in 34 countries, including 26 in the Americas.

GBS, in which the nervous system is attacked by the body's immune system, causes gradual weakness in the legs, arms and upper body and sometimes leads to total paralysis.

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Zulay Balza was diagnosed with Guillain-Barre Syndrome, a disorder in which the immune system attacks the nervous system, causing muscle weakness and sometimes paralysis

According to the Health Institute of Norte de Santander state, Colombia, 30 cases of Guillain-Barre Syndrome were diagnosed in the state since a Zika outbreak

Venezuela has reported 252 cases of Guillain-Barre occurring at the same time and place as Zika infections, WHO said

'The cause of the increase in GBS incidence observed in Brazil, Colombia, El Salvador and Suriname remains unknown, especially as dengue, chikungunya and Zika virus have all been circulating simultaneously in the Americas,' WHO added.

Venezuela has reported 252 cases of Guillain-Barre occurring at the same time and place as Zika infections, it said. 'Zika virus infection was confirmed for three of the GBS cases, including one fatal case.'

Venezuela's President Nicolas Maduro said on Thursday that three people had died of complications linked to Zika virus and that suspected cases of Zika had risen to 5,221.

Even in the best of settings, 3 to 5 percent of Guillain-Barre patients die from complications, which can include paralysis of the muscles that control breathing, blood infection, lung clots or cardiac arrest, according to the WHO.

In French Polynesia, all 42 GBS cases identified during the Zika virus outbreak in 2013-2014 tested positive for dengue and Zika virus infection, the WHO said.

There is no proven link between the Zika virus, the birth defect microcephaly and Guillain-Barre syndrome, but senior WHO expert Marie-Paule Kieny said on Friday that scientists suspected on and might be able to confirm it within weeks.

A sharp increase in microcephaly cases in Brazil triggered a global health emergency over the mosquito-born virus.

The feared link between the illness, and the birth defect, which causes babies to be born with abnormally small heads and often severe brain damage, prompted the WHO to declare the outbreak a crisis.

And it has spurred a race to develop a vaccine, medication and better diagnostic tests for the disease, which had previously only thought to be a relatively mild illness.

The WHO said US government scientists and an Indian biotechnology firm were the front-runners in the vaccine effort but said it would take at least 18 months to start large-scale clinical trials of potential preventative shots.

The UN health agency also for the first time advised pregnant women to consider delaying travel to Zika-affected areas.

In addition, new findings about Zika lingering in the semen of an infected British man raised fresh concern about sexual transmission of the virus.

Brazil, which is at the centre of the outbreak that has seen Zika spread to more than 30 countries, is set to host the Olympics in August in Rio de Janeiro, an event expected to draw hundreds of thousands of athletes, officials and spectators.