Side-by-Side il recently, the Zika virus was a rare and mild public lth concern and little was known about it. In early 2015, zil reported an epidemic of Zika viral infection. Reports n followed of unusual numbers of neurological orders such as microcephaly in newborns, a condition racterized by a very small head and poor brain growth. Macmillan Learning Explain why we cannot conclude from this information alone that Zika infections cause microcephaly in newborns. There may be a lurking variable that is increase in both Zika infections and mi in newborns. It is not biologically plausible for the Z cause brain issues for newborns. One needs to conifirm that microceph defects occur before the Zika virus inf O Correlation and regression lines desc linear relationships, so no conclusion be drawn.