A team from The University of Texas Medical Branch at Galveston has found a Zika virus mutation that may be responsible for the outbreak that occurred in 2015 and 2016.
Mosquitoes primarily transmit the Zika virus. Because it circulates between mosquitoes and animals/humans, they are prone to genetic mutations, making them highly capable of emerging and causing epidemics.
The UTMB team has identified a mutation in the Zika envelope protein that can enhance mother-to-baby transmission in pregnant mice, increase neurological disease and lethality in newborn mice and elevate virus levels in the blood of infected non-human primates.
“Our study demonstrates that the Zika envelope mutation V473M, which just occurred before the 2015 epidemic in the Americas, enhances Zika virus particle assembly in infected cells. The enhanced virus assembly leads to increased human disease and maternal transmission,” Pei-Yong Shi, I.H. Kempner professor of Human Genetics at UTMB, said. “The viral genetic change reported here, combined with the naïve herd immunity, may have accounted for the Zika epidemic and severe diseases in 2015 and 2016.”
The UTMB team has received grants from the National Institutes of Health and philanthropic support from the Sealy & Smith Foundation; Robert J. Kleberg, Jr. and Helen C. Kleberg Foundation; John S. Dunn Foundation; Amon G. Carter Foundation; Gillson Longenbaugh Foundation; Summerfield G. Roberts Foundation.
“RNA viruses are the pathogens most often responsible for outbreaks and epidemics, including Ebola virus and SARS-CoV-2, the virus causing COVID-19,” Shi said. “Understanding the mechanisms of viral emergence and transmission is essential to detect and respond to future outbreaks. Although the world is currently focusing on COVID-19, I am certain that COVID-19 will not be the last emerging virus we face. Moving forward, building public health capacity and countermeasure technology are the only effective means to overcome these threats.”