Since early last year, worries over the spread of the Zika virus have continued to mount. The virus, which has been shown to cause birth defects in pregnant women, first gained a foothold in Latin America and has since spread to areas across the U.S.
While locally transmitted cases of Zika have been concentrated in the South, in areas like Florida and Texas, new research from Entomological Society of America suggests that the risk of a large-scale outbreak is lower than many believe. While the climate around the U.S. is conducive for mosquitoes – which carry the virus – to thrive, researchers say that socioeconomic factors give the U.S. and other developed countries an advantage.
"It seems clear that the main factors keeping outbreaks of these diseases from occurring today are socioeconomic such as lifestyle, housing infrastructure, and good sanitation. While such conditions are maintained, it seems unlikely that large scale local transmission will occur, especially in northern states," the authors of the study said.
In their paper, the researchers point out that diseases transmitted by the Aedes aegypti mosquito, such as Zika, yellow fever, dengue, and chikungunya, occur primarily in developing countries with low socioeconomic conditions.
While the diseases have been known to travel to other areas like the U.S., they say that certain factors like the absence of air conditioning, lack of screen windows, and prevalence of water shortages are main contributors to outbreaks of these diseases.
While this is good news for most Americans, the authors say that there are other factors that can increase risk for developed countries. One of them, which we previously discussed after the disaster of Hurricane Matthew, is how natural disasters could increase infection rates.
"If the isolation between humans and Ae. aegypti mosquitoes in the U.S. is primarily caused by lifestyle and living infrastructure associated to socioeconomic conditions, these could be threatened by massive natural disasters, or any other event that disrupts current infrastructure," they write.
Problematic on small scale
Additionally, the researchers say globalization could affect infection rates in developed countries. Travelers who visit areas with high infection rates can often bring the disease back home with them, which could cause health crises in small regions.
"The growing interconnection of our global society makes global public health-related issues, such as sanitation and the lack of a continuous supply of running water in developing countries, an important concern to developed countries, as these developing countries may serve as a source of imported cases of disease," they said.
For these reasons, the researchers think it more likely that Zika will not be a problem on an epidemic level, but one can pose problems on a local, small-scale level in affected communities. The full study has been published in the Journal of Medical Entomology.