Researchers have noted four other features unusual for babies born with congenital infections due to Zika virus infection.
The Zika virus is generally associated with warmer climates—and no wonder, given its incidence in places like Brazil and Puerto Rico.
Even here, in the United States, the only “locally transmitted” cases—those resulting from mosquito bites sustained locally—have, to date, been confined to balmy south Florida. However, as researchers discover additional consequences of congenital Zika virus infection, the fear of infection with the Zika virus is not contained in the Southern hemisphere. Individuals who travel to affected regions, or who have contact with infected bodily fluids (through sex or other close contact) are also at risk.
On November 3, the Centers for Disease Control and Prevention (CDC) announced that Minnesota—America’s great white north—has 53 cases of the mosquito-borne virus, according to a report on a local CBS affiliate.
All of these cases resulted from travel to where the Zika virus is rampant, and not from bites from local Aedes aegypti mosquitos. However, the news adds credence to statements from CDC director Thomas Frieden, MD, MPH, and others in October that Zika is likely to spread across the country long before a viable vaccine and/or treatment is available.
Needless to say, that is not good news for American women who are pregnant or plan to become pregnant, given the virus’ effects on the health of babies born to infected mothers. Links between the birth defect microcephaly and Zika have been well documented, but a review of clinical reports published on November 3rd in JAMA Pediatrics, found 4 other features unusual for babies born with congenital infections: thin cerebral cortices (including subcortical calcifications), macular scarring (with focal pigmentary retinal mottling), congenital contractures, and early hypertonia (with extrapyramidal involvement). Based on these findings, the authors, from the CDC and Brazil, believe that congenital Zika syndrome, a term that experts have been using since earlier this year, characterize the effects of the disease on newborns, is the result of central and peripheral nervous system damage caused by the virus.
“Complete clinical descriptions of additional affected fetuses, infants, and young children are needed to help verify conclusions built on sparse data and to go beyond the current phenotype, which likely represents a portion of a broader spectrum,” the authors wrote. “In particular, more data are needed on infants with congenital [Zika virus] infection who do not have microcephaly at birth and the brain findings in these infants. In addition, knowledge about the frequency in which the various components co-occur in an infant, as well as whether any component(s) are mandatory features, is lacking at this time.”
According to the CDC’s recent weekly Zika report, more than 1,100 pregnant women in the continental United States have been diagnosed with Zika. Worldwide, UNICEF has declared that preventing the spread of Zika and educating and supporting families and children affected by the virus a priority.
Brian P. Dunleavy is a medical writer and editor based in New York. His work has appeared in numerous healthcare-related publications. He is the former editor of Infectious Disease Special Edition.