We Know Zika Is A Big Problem In Puerto Rico. We Just Don't Know How Big.

The numbers don't add up.
05/19/2017 04:25pm ET | Updated May 26, 2017

The Zika virus is still a significant threat to Puerto Rico, even though it has all but disappeared from the U.S. news cycle and, state health officials say, mosquitos in Florida.

The climate in Puerto Rico ― a U.S. territory that has been struggling with a budgetary crisis and has had little intervention from state health programs ― is ideal for the aedes aegypti mosquitos that spread infectious diseases. There have been 40,000 confirmed Zika cases among residents.

All of this could also affect travelers to the island. Little information is coming from Puerto Rico, which could give tourists a misplaced sense of security about the Zika risk there.

A JAMA pediatrics study published in October 2016 predicted that Puerto Rico would see 110 to 290 Zika-related microcephaly cases between mid-2016 and mid-2017. Microcephaly is a severe birth defect connected to developmental disabilities and babies being born with smaller-than-average heads.

But at last count, Puerto Rican officials had only reported 16 babies born with microcephaly, a staggeringly low figure considering the island has had 3,200 confirmed Zika cases in pregnant women since the beginning of the outbreak.

These numbers don’t add up, according to some health officials who talked to health news site Stat under the condition of anonymity. They said Puerto Rico might be underreporting its Zika problem for tourism reasons.

The U.S. isn’t keeping track of Zika in Puerto Rico. The Centers for Disease Control and Prevention isn’t reporting adverse pregnancy outcomes for U.S. territories ― and according to the agency website, Puerto Rico is using different criteria to report Zika-related birth defects than the United States is.

Angel Valentin via Getty Images
The mosquito net-covered stroller where 2-month-old twins Misael and Ismael Carrasquillo slept during a visit for regular vaccinations at Puerto Rico's Concilio de Salud Integral in Loiza in 2016.

It’s also possible that mothers of babies born with birth defects may be unwilling to talk about it publicly. There’s a strong stigma surrounding Zika virus, Dr. Carmen Zorrilla, who runs the Maternal Infant Studies Center at the University of Puerto Rico hospital, told NPR.

“You have pregnant women with a viral disease that may cause birth defects, which is serious,” Zorrilla said. “And then you’re blaming them for getting it.”

The U.S. had more than 5,200 reported Zika cases as of May 17, including 218 local mosquito-born transmissions in Florida and six such transmissions in Texas, according to the CDC. There have been 1,845 cases of Zika in pregnant women in the U.S., 64 babies born with Zika-related birth defects and eight cases of Zika-related pregnancy loss.

The CDC awarded Puerto Rico’s health department $9.5 million to set up a Zika tracking system for pregnant women and to identify Zika-affected infants and fetuses. But a deep rift between the CDC and Puerto Rican heath officials means the two groups aren’t collaborating, Stat reports.

It’s not clear how long it will take for up-to-date, accurate information about Zika and microcephaly in Puerto Rico to come to light.

“I see pregnant women every day,” Zorrilla told Stat. “What am I to tell them?”

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