Photo: Cynthia Goldsmith. Electron micrograph of Zika virus. Virus particles are 40 nm in diameter, with an outer envelope and... 30 Jan ZIka and microcephaly Gail Hart | microcephaly, pregnancy, zika | 0 Photo: Cynthia Goldsmith. Electron micrograph of Zika virus. Virus particles are 40 nm in diameter, with an outer envelope and...