On February 25, 2017, at The First International Zika Conference, Carmen D. Zorrilla, MD, professor of obstetrics and gynecology, University of Puerto Rico, School of Medicine, shared her research which aimed to evaluate the growth patterns of fetuses whose mothers acquired Zika virus during pregnancy “and showed no prenatally detectable structural anomalies or maternal conditions that could affect fetal growth.”
Dr. Zorrilla opened her presentation by providing conference attendees with a brief overview of the Zika epidemic in Puerto Rico, sharing that the first case was reported back in December 2015. She said, “It was estimated that 50% of the Puerto Rican population would get infected with Zika virus, so we estimated that maybe 6,000 to 7,000 pregnant women would get infected during 2016.”
When it comes to Zika testing in Puerto Rico, the Puerto Rico Department of Health followed the Centers for Disease Control and Prevention’s guidelines and started testing all pregnant women during their 1st and 2nd trimester regardless of whether they were presenting with symptoms or not. Later, they expanded testing to include the 3rd trimester as well. Healthcare officials used the Trioplex Real-time reverse transcription polymerase chain reaction (RT-PCR) to detect the Zika virus and distinguish it from Dengue and Chikungunya.
Dr. Zorrilla shared that, as of February 17, 2017, Puerto Rico had 38,733 cases of confirmed Zika virus infection. Of these confirmed cases, 3,076 were pregnant women and 57% of these women had been diagnosed while symptomatic; 43% “were diagnosed by routine testing during pregnancy.” Dr. Zorrilla then showed a graph depicting the confirmed Zika cases in pregnant women from January 29, 2017 to February 4, 2017, noting that, “the curve is flattening, but we are still seeing new cases of pregnant women diagnosed.”
“Severe brain damage caused by Zika virus infection has been well-documented with rates of congenital Zika syndrome (CZS) between 1-11%,” according to Dr. Zorrilla. She continued, “It can be diagnosed by ultrasound. Some of the most characteristic patterns of ultrasound findings include: ventricular dilatation and abnormal cerebral development, [and] also intracranial calcifications that are scattered all over the fetal brain without a significant pattern or flow.”
As mentioned in previous presentations at the conference, Dr. Zorrilla shared that the full spectrum
of Zika virus remains to be defined. She explained, “We believe that we already have the CZS, the most severe manifestation of the infection, but we believe that there is a full range of disease that might go from normal to severe. We wanted to see and examine what was happening in the fetuses of women diagnosed with Zika infection who showed no brain abnormalities from ultrasound [and in] fetuses that looked normal on ultrasound, in terms of the brain, [we wanted to know if Zika had] any impact on their [head] growth.”