Researchers Investigating Zika’s Connection to Other Birth Defects

— -- Researchers continue to investigate the devastating effects of the Zika virus on fetal development and are now studying whether the virus also impacts joint, eye and hearing development as well.

Officials from the U.S. Centers for Disease Control and Prevention (CDC) confirmed Wednesday that the virus causes microcephaly, a dangerous birth defect characterized by an abnormally small head and brain.

CDC Director Dr. Tom Frieden said this was a "turning point" in our understanding of the virus that has continued to spread throughout the Americas.

"We believe microcephaly will be a part of a range of birth defects that may affect women infected at a particular time or at any time during pregnancy," Frieden told reporters yesterday.

Multiple medical research papers published on Zika have revealed that the virus is likely much more dangerous for developing fetuses than previously thought. While the virus was discovered in 1947, it was not linked to fetal abnormalities until an outbreak in Brazil last year.

Brain abnormalities is a major concern for researchers because microcephaly can lead to serious developmental delays later in life. Other serious brain defects have been detected in children with microcephaly, including calcifications of the brain, atrophy of the brain and the absence of certain brain structures such as the corpus callosum and the thalamus.

These findings were based on small case reports and researchers are still investigating to confirm these findings in a larger population.

But problems with brain development is not the only concern. Some infants also suffered from contracted joints, club feet, visual problems and hearing impairment after being exposed to Zika in utero. One study published in February found that some infants exposed to the virus had ocular defects including atrophied retinas, abnormal iris pigmentation and lens that moved out of place.

Dr. Buddy Creech, an associate professor of Pediatric Infectious Diseases at Vanderbilt University Medical Center, said other viruses, including herpes and rubella, are known to cause ocular birth defects in infants.

"This idea of a virus contracted during pregnancy causing damage to the central nervous system is not a shocking finding," Creech said in an earlier interview.