US, Brazilian researchers launch massive Zika virus study

Sponsored by the National Institutes of Health (NIH) in Washington and its Brazilian counterpart Fiocruz, "The Zika in Infants and Pregnancy Study" (ZIP) aims to enroll upwards of 10,000 pregnant women ages 15 and older. The study will open first in Puerto Rico and expand to Brazil, Colombia and other areas affected by the virus, up to 15 sites.

Scientists will follow study participants from the first trimester through at least the first year after birth. "The full scope of the effect of Zika virus in pregnancy has not yet been fully determined," said Anthony S. Fauci, director of the National Institute of Allergy and Infectious Diseases.

"This large prospective study promises to provide important new data that will help guide the medical and public health responses to the Zika virus epidemic." Worldwide, the virus is actively spreading in some 60 countries and territories.

Zika is primarily transmitted through bites from infected mosquitos, as well as sexual transmission from an infected mother to her unborn child. The virus has sparked international concern because it is linked to a spike in microcephaly, a condition that causes babies to be born with abnormally small heads and potential neurological damage.

Doctors have also connected Zika to miscarriage and stillbirth, as well as eye defects, hearing problems, reduced growth rates and brain development delays in newborns. The study will include analysis of birth outcomes, pre-term birth, microcephaly cases and other problems, taking into account environmental influences and other infections, including the dengue virus.

By comparing groups that include both infected and non-infected mothers and children, researchers anticipate the study will inform communities on how to better safeguard the health of mothers and children.