Zika Virus News Update: Three New Things You Should Know

Every day, researchers from around the globe are making advancements when it comes to better understanding Zika, a virus that poses a great threat to pregnant mothers and their unborn children. In this update, we’ve compiled some of the latest news associated with the mosquito-borne virus that has been revealed this past week.

#1: Zika Transmission Depends on Time Spent Outdoors

A recent study conducted by researchers from Northeastern University in Boston and the University of Miami explored the link between Zika transmission and how much time individuals spend outdoors. The researchers surveyed 270 individuals who reside in Miami-Dade, Florida, an area that has been heavily hit with Zika virus in the past. Using a computational model to evaluate “how Zika transmission dynamics related to time spent outdoors,” the researchers found that time residents spent outside were “highly variable,” according to the recent PLOS press release. The majority of the individuals surveyed reported spending <2 hours a day outside. However, that was not the case for everyone; there was a small percentage of individuals who reported spending as long as 10 hours outside per day.

The computational model revealed that “this heterogeneity—compared to a hypothetical population in which everyone spends the same average amount of time outside&mdash;leads Zika virus to infect fewer people but spread at a faster pace from person-to-person,” according to the press release.

The findings led researchers to postulate that, “Operational control efforts could be prioritized and directed towards areas characterized by high levels of human outdoor activities, such as recreational areas and tourist attractions, rather than, for instance, on residential areas.”

#2: Infants with Congenital Zika Syndrome Suffer Severe Visual Impairment

Two studies recently conducted in Brazil sought to evaluate visual functionality in infants with suspected and confirmed congenital Zika syndrome (CZS).

The first study examined 70 infants with microcephaly and found that 18 had intraocular abnormalities (including macular chorioretinal atrophy, mottled retinal pigment epithelium, and optic nerve pallor), and 7 of the infants “had strabismus or nystagmus without intraocular abnormalities.” Furthermore, 11 infants tested for visual acuity were found to be “below normal range.”

The second study involved infants from Pernambuco, Brazil, with confirmed Zika virus. The researchers found that all 32 infants that were included in the study suffered from visual impairment; 14 of the infants had retinal and/or optic nerve damage as well as neurological abnormalities detected at birth.

However, lead investigator, Liana O. Ventura, MD, PhD, Altino Ventura Foundation, and the Department of Ophthalmology, HOPE Eye Hospital, in Recife, Brazil, commented in a recent press release, “Surprisingly, the present study revealed that, regardless of fundus involvement, all infants presented with visual impairment, suggesting that visual impairment is most likely related to the extensive damage to the central nervous system.” She added, “These findings reinforce our supposition that brain damage is the main etiology for visual impairment in CZS.”

#3: Students Assist in Post-Hurricane Harvey Mosquito Control Efforts

In the wake of Hurricane Harvey, millions of mosquitoes have emerged in the southeastern regions of Texas, prompting health officials to consider the threat of mosquito-borne diseases.

In response to this threat, 2 students from the University of Wisconsin-Madison—Melissa Farquhar and Erin McGlynn&mdash;have volunteered to “monitor for disease-spreading species of mosquitoes and determine the effectiveness of control efforts,” according to a recent press release issued by the university.

Clarke, a mosquito control company that had been enlisted by Texas to enact control efforts, made the 2 students temporary employees, to assist in monitoring the influx of mosquitoes.

“The floodwater mosquitoes that Texas is dealing with lay eggs in the soil that hatch and develop into adults quickly after floods. The widespread flooding produced by Hurricane Harvey has led to far more mosquitoes emerging than normal,” according to the press release. In fact, the release notes that in a single night, a mosquito trap might capture 10 to 20 mosquitoes. However, workers are reportedly finding several thousand mosquitoes captured in each trap in areas throughout Houston.

This poses a problem because even though floodwater mosquitoes do not typically spread infectious diseases such as Zika or West Nile virus, standing water left behind after the floodwaters recede provide prime breeding grounds for the Aedes aegypti mosquitoes that transmit these diseases.

To keep up-to-date on the latest Zika news, visit our Zika page.