Thanks to Greg Folkers for sending the link to this correspondence, published today in NEJM: Computed Tomographic Findings in Microcephaly Associated with Zika Virus. Click or tap through for the full report. The conclusion:
Intrauterine ZIKV infection appears to be associated with severe brain anomalies, including calcifications, cortical hypogyration, ventriculomegaly, and white-matter abnormalities, although we cannot determine with certainty when ZIKV infection may have occurred during fetal development in these 23 infants. Our findings are nonspecific and may be seen in other congenital viral infections.
The global presence of cortical hypogyration and white-matter hypomyelination or dysmyelination in all the infants and cerebellar hypoplasia in the majority of them suggest that ZIKV is associated with a disruption in brain development rather than destruction of brain. The neuronal and glial proliferation as well as neuronal migration appear to be affected.
The mothers of the microcephalic infants in our study population had symptoms (e.g., low-grade fever and cutaneous rash) that were compatible with ZIKV infection during the first or second trimester of pregnancy, similar to the findings in other studies.
Tang et al. found that ZIKV directly infects human cortical neural progenitor cells with high efficiency, resulting in stunted growth of this cell population and transcriptional dysregulation. This observation supports the type of disruptive, anomalous brain development that we found in these infants.
