Miami's mosquitoes are getting more comfortable
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Noticed a slight uptick of mosquitoes buzzing around? We have the proof you're itching for.
Driving the news: The number of "mosquito days" — those with the hot and humid weather the flying insects crave — has trended upward in Miami over the past several decades, according to a new analysis from nonprofit research organization Climate Central.
- The report defines a "mosquito day" as one with an average relative humidity of 42% or higher, plus daily temperatures of 50°–95° F — our region's sweet spot.
Why it matters: Mosquitoes are more than just a nuisance — they're a public health threat, carrying diseases such as malaria, West Nile, Zika and more, Axios' Alex Fitzpatrick and Kavya Beheraj report.
Threat level: Florida is now under a statewide mosquito-borne illness advisory after four Sarasota County residents recently contracted malaria.
- Health officials also issued a mosquito-borne illness alert for Miami-Dade County after finding two cases of dengue fever this year.
- Mosquito numbers typically spike at the start of the rainy season in May.
By the numbers: Miami had 355 mosquito days in 2022 compared to 353 in 1979.
Yes, but: Nearly all the days in a year being hospitable to mosquitoes is inhospitable to us.
The big picture: 71% of the 242 locations Climate Central analyzed saw an increase in mosquito days between 1979 and 2022.
Between the lines: Some locations — particularly in the South — are actually getting too hot for mosquitoes, the analysis notes.
- They don't thrive in temperatures above 95°, an increasingly common reading in southern summers.
Of note: Other factors, such as rainfall and drought, can also influence mosquito activity.
- They breed in pools of standing water, common after major storms.
What's next: Experimental efforts to control mosquito populations by releasing genetically modified versions of the insects into the wild are underway in the Florida Keys and elsewhere.
- Those projects, however, are controversial among some locals and skeptics who view them as tampering with the natural ecosystem.