The World Health Organization has confirmed that the available scientific evidence is strong enough to arrive at a consensus that Zika virus infection is indeed the cause for the recent increase in number of cases of  Guillain-Barré syndrome and foetal microcephaly.

Guillain-Barre  syndrome produces acute, usually ascending, flaccid paralysis of muscles and can be life threatening when it affects respiratory muscles, though most recover with prompt treatment.

It is currently estimated that chances of getting GBS is 0.24 per 1000 Zika infections and that of microcephaly in foetus is 95 per 10000 Zika infections in first three months of pregnancy.

As of now 62 countries has reported Zika infections. More than 1000 cases of microcephaly had serological evidence of Zika infection. More than 400 cases of GBS also had similar serological evidence.

Though the infection is mainly mosquito borne , cases of sexual transmission has also been identified in several countries. No definite treatment is available now and most patients recover without any residual defect.

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