The Maricopa County Department of Public Health announced Monday that it had confirmed a human case of dengue fever that is believed to have originated in an infected mosquito in Arizona.
“Routine mosquito surveillance performed by Maricopa County Environmental Services Department (MCESD) has detected the dengue virus in a mosquito trap in one neighborhood in the county,” the health department said in a news release.
The mosquito-borne illness annually infects 400 million and kills up to 40,000 people, according to the Centers for Disease Control and Prevention, but most cases reported in the lower 48 states, the CDC states on its website, have been “in travelers infected elsewhere.”
Officials in Maricopa County, which includes Phoenix and its densely populated surroundings, are sending teams out to area neighborhoods to offer free testing for the disease and information on how to prevent mosquito bites and breeding.
As global temperatures have continued to rise over the last century due to climate change, dengue fever has spread dramatically. A study published this year in the journal Frontiers in Public Health found that, thanks to climate change, the disease will “affect 60 per cent of the world’s population by 2080.”
“Currently, dengue is taking its toll, and climate change is one of the key reasons contributing to the intensification of dengue disease transmission,” the study states. “The most important climatic factors linked to dengue transmission are temperature, rainfall, and relative humidity.”
At present, the estimated 100 million people who fall ill from dengue each year can experience symptoms ranging from those similar to the flu to severe bleeding, organ failure and death. The World Health Organization notes that the swift rise in the number of dengue cases is a recent phenomenon.
“The number of dengue cases reported to WHO increased over 8 fold over the last two decades, from 505,430 cases in 2000, to over 2.4 million in 2010, and 5.2 million in 2019. Reported deaths between the year 2000 and 2015 increased from 960 to 4032, affecting mostly younger age group,” the WHO states on its website, adding, “Before 1970, only 9 countries had experienced severe dengue epidemics. The disease is now endemic in more than 100 countries in the WHO regions of Africa, the Americas, the Eastern Mediterranean, South-East Asia and the Western Pacific.”
A paper published in 2020 by researchers in Taiwan and highlighted by the National Institutes of Health links rising temperatures to the sharp increase in the number of dengue cases worldwide.
“Climate change is regarded as one of the major factors enhancing the transmission intensity of dengue fever,” the paper states.