Three new studies reporting on the effects of the Zika virus outbreak in Brazil which will be presented next week at the annual meeting of the Radiological Society of North America (RSNA) provide more insight into Zika effects.
The first study looks at CT findings of the central nervous system in 16 newborn babies with congenital Zika virus infection confirmed by tests in cerebral spinal fluid. The researchers identified a pattern of CT brain findings in the babies, including decreased brain volume, simplified gyral pattern, calcifications, ventricular dilatation and prominent occipital bone. According to the author Natacha Calheiros de Lima Petribu, M.D., from the Department of Radiology at Barão de Lucena Hospital, “our study proves that Zika virus infection can cause congenital brain damage in babies with and without microcephaly”.
Another study analyzed the imaging results of three target groups affected by Zika: adults who developed acute neurological syndrome, newborns with vertical infection with neurological disorders, and pregnant women with rash outbreaks suggestive of Zika. Many of the adults had symptoms of Guillain-Barré syndrome, a rare disorder in which the body’s immune system attacks the nervous system causing rapid onset muscle weakness. A few showed inflammation of the brain and spinal cord (Bickerstaff’s encephalitis) or brain stem and spinal cord lesions. Common MRI findings included enhancement of certain spinal and facial nerves. In the newborns, MRI showed orbital injuries and anatomical changes in brain tissue.
In a third study, ultrasound and fetal MRI were performed on pregnant patients with Zika virus infection at different gestational ages. Once the babies were born, they underwent ultrasound, CT and MRI. The researchers then created 3-D virtual and physical models of the skulls. More than half the babies had microcephaly, brain calcifications and loss of brain tissue volume, along with other structural changes.
Understanding Zika
Zika is mainly spread to humans via the bite of an infected mosquito. Symptoms may include fever, rash, joint or muscle pain, headache and bloodshot eyes. More serious conditions, such as Guillain-Barré syndrome, have been associated with Zika infection in adults, but are uncommon. Many adults infected with Zika have no symptoms at all.
Zika appears to be most dangerous when transmitted from a pregnant mother to her fetus during the first trimester of pregnancy, increasing the likelihood of severe brain defects in the baby, including microcephaly. Zika has also been linked to eye defects, hearing impairment and stunted growth in babies.
Pregnant women and women who are considering becoming pregnant should avoid visiting areas where infected mosquitoes are known to be present. However, if women live in areas where the mosquitoes are present, the recommendation of the Centers for Disease Control and Prevention (CDC) is to wear clothes that protect from mosquito bites, use mosquito repellent and get appropriate testing, including routine prenatal care and an ultrasound at 18 to 20 weeks. Pregnant women who are worried that they may have contracted the virus should speak with their obstetrician to initiate testing.
Read also: Zika Virus: What You Need to Know and How to Protect Yourself
