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Acknowledge Uncertainty

This information is for historic and reference purposes only.  Content has not been updated since the last reviewed date at the bottom of this page.
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In any emergency or disease outbreak, people want to know as much as they can about potential risks. Not all questions can be answered right away. Reports from health officials in Brazil about the increase in cases of a severe birth defect—microcephaly—during a significant outbreak of Zika virus disease have raised many questions. While Zika virus has been associated with microcephaly in babies whose mothers were infected with Zika while pregnant, there is still a lot that is not known about this possible link.

During a crisis, it is important to tell your audience:

  • What you know
  • What you don’t know
  • What process you are using to get the answers

CDC’s key messages and communication materials for the current outbreak highlight what we know about Zika. We know that the virus can be spread from a pregnant mother to her fetus during pregnancy, and that having Zika virus during pregnancy has been linked to microcephaly, fetal loss, and other poor pregnancy outcomes.

CDC also states what we do not know yet. We are still investigating the likelihood of Zika passing to a fetus from an infected pregnant woman, if there is a time during the pregnancy when the Zika virus is more likely to harm the fetus, or if a baby will develop birth defects if infected.

To help answer these questions, CDC is conducting research and surveillance activities in collaboration with health officials in other countries, and we are establishing a Zika pregnancy registry in the US. And, as we learn more, we continue to update our audiences with new facts, new questions, and information on how we’re working with our global public health partners to address this emerging situation.

For more resources and information on CERC, please see Crisis and Emergency Risk Communication, 2014 Edition or Crisis and Emergency Risk Communication Pandemic Influenza, 2007.

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