Weather Heating Up the Spread of Zika?
Zika virus – the name itself instills fear in many today, whether they are North or South of the equator. It may have sound foreign to Americans a few years ago; however now it’s been creeping its way north, one degree at a time, same as the global rise in temperature.
Zika is a flavivirus, a type of virus that mutates frequently, and is spread through animal vectors, in this case: the A. aegypti mosquito. Numerous birth defects and other side effects have been attributed to a new mutation in the Zika virus; most commonly, infected pregnant mothers have been giving birth to babies with abnormally small heads and neurological disorders like Guillan-Barre syndrome. Until recently, most of these tragic stories have been occurring mainly in Central and South America, where the humid, warm climate makes for an optimal mosquito breeding ground. But as of late, there have been outbreaks reaching as far north as the Southeastern U.S, in states such as Florida. Should we be concerned? Is the trend going to continue northwards?
Of course there are many factors to consider in the outbreak of a mosquito-borne disease, but the climate is one that is particularly important to note. Temperature, humidity, and precipitation all affect how frequently mosquitos feed, how many offspring they have, and how long their average lifespans are. According to Tom Scott, a professor of entomology and epidemiology at the University of California Davis, a mosquito lives an average of 10-12 days – the amount of time normally needed for a virus to incubate within the cold-blooded insect. Sometimes the mosquito will even die before it’s able to spread the disease. However with the warming temperatures, this incubation period is being shortened, giving the mosquito more time to spread the disease while it’s still alive. So it is in ways like this, that biology and weather cannot be treated as two separate entities; there’s a noteworthy link that needs to be investigated into further there, especially in the onslaught of this public health emergency.
The World Health Organization (WHO) published an article warning that an increase of even 2-3 degrees Celsius can put at least 7 percent more people globally at risk of contracting malaria, another mosquito-borne disease. Seven percent may seem like a low number, but if you put that in perspective globally, that’s another several hundred million people. That same concept can apply for Zika as well. So even though the warmer months of the year are coming to an end, that doesn’t mean the spread of Zika will stop heating up.