Following a review of existing research on Zika virus, the Centers for Disease Control and Prevention (CDC) has concluded that Zika virus causes microcephaly and other severe brain defects in babies. The CDC finding  was published in the New England Journal of Medicine.

In their review, researchers looked at studies conducted in Brazil and French Polynesia during recent outbreaks of Zika virus. In September 2015, researchers in Brazil reported an increasing in the number of infants with microcephaly. French Polynesia noted a similar increase of this brain defect during an outbreak there in 2013 and 2014.

One Brazilian study of 88 pregnant women infected with Zika who underwent prenatal ultrasonography testing found fetal abnormalities in 29 percent of the cases.

The CDC is concerned that the American public is not well-informed or well-prepared with regard to the Zika virus despite its best efforts. An Associated Press poll found that four out of 10 Americans have heard little or nothing at all about Zika virus.

Ninety percent of Americans who have heard of Zika know it can be spread through the bite of a mosquito carrying the virus but only 57 percent were aware the virus can be spread through sexual intercourse with an infected person.

To date, Americans infected with Zika have acquired it through travel to countries with active mosquito-borne transmission of the virus. The CDC has posted travel warnings for Americans traveling to these Latin American and Caribbean countries.

The CDC has advised women who are pregnant or hoping to become pregnant to avoid travel to Zika- affected areas. It has also expanded the initial guidance to include women’s partners, as it has become more clear that the virus is spread through sexual contact.

Currently, the mosquitoes that carry the virus, Aedes aegypti and Aedes albopictus, are present in at least 30 U.S. states, according to the CDC. Since no vaccine exists to prevent Zika, the agency is recommending the following preventive measures :

  • Wear long-sleeved shirts and long pants to prevent mosquito bites.
  • Stay in places with air conditioning or that use window and door screens to keep mosquitoes outside.
  • Use insect repellents, even if pregnant or breast-feeding.
  • Treat clothing with permethrin.
  • Prevent sexual transmission by using condoms or abstaining from sex.

Reviewed by Dr. David Priest, medical director for infection prevention and antimicrobial stewardship, Novant Health

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