In the United States, the Gulf Coast, especially the Texas Gulf Coast, is vulnerable to the threat of arboviruses – viruses transmitted by insects. A major reason is the warm and moist Gulf Coast climate that favors survival and overwintering of mosquitoes.
Houston and Harris County for instance, are home to two major mosquito species – Aedes aegypti and Aedes albopictus – that can transmit several arboviruses such as dengue, yellow fever, and chikungunya virus. Research led by Dr. Kristy O. Murray provided strong evidence that dengue emerged in Houston between 2003 and 2005. Our region is also home to the Culex mosquitoes that transmit West Nile virus infection. These arbovirus infections have important health and economic consequences for the region.
The latest threat to our region could be a new virus known as the Zika virus that recently emerged in Latin America. The first case occurred in 2014 on Easter Island, Chile. in May of this year the first cases in Brazil were observed to occur in association with local transmission of the virus. The Brazilian state of Bahia, for instance, was noted to be particularly hard hit, as were several states in the nearby northeastern region.
This month the Pan American Health Organization, the regional organization of the World Health Organization, issued an alert regarding Zika virus transmission in Brazil, Chile (on Easter Island), Colombia, El Salvador, Guatemala, Mexico, Paraguay, Suriname, and Venezuela.
Of particular concern is the link noted between Zika virus and neurological illness, but especially a possible role in congenital infection. Newborn babies born to mothers infected with Zika virus have been noted to possibly be at increased risk of congenital birth defects including a condition known as microcephaly. Microcephaly is a serious condition associated with below normal intelligence and other central nervous system findings.
What does this mean for Texas and the Gulf Coast? To our knowledge, Zika virus has not yet appeared in our area, but we know we are vulnerable to arbovirus infections. We therefore need to be cognizant of the possibility of Zika virus gaining a foothold in our area in the future.
The summer and fall months are a particularly troubling time for mosquitoes and arbovirus infections. Therefore we at our National School of Tropical Medicine at Baylor College of Medicine hope to conduct future studies on the potential risk of Zika in Harris County, Texas and the Gulf Coast.
The Sabin Vaccine Institute and Texas Children’s Hospital Center for Vaccine Development develop vaccines for neglected diseases, but has not yet started a Zika project. However, this too could be an area of future work.
As we learn more about Zika virus and its rise in the Americas, we hope to keep you informed on our progress and tracking of this important emerging infection.