The WHO and CDC state that evidence linking Zika and microcephaly is currently inconclusive. Although Brazil has reported almost 4,000 cases of microcephaly, genetic material from Zika has been identified in only six infants. The presence of such material may as yet be circumstantial.

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The WHO and CDC state that evidence linking Zika and microcephaly is currently inconclusive. Although Brazil has reported almost 4,000 cases of microcephaly, genetic material from Zika has been identified in only six infants. The presence of such material may as yet be circumstantial.