Chickgungunya A Mouthful that is Spreading



Global warming is worsening the spread of Chickungunya (chicken-GOON-y) in South America. Even Texas and Florida have reported local transmission.  CHIKV, its shorter name, is a zoonotic pathogen spread by mosquitos. That means it’s an infection that spreads between people and animals, but is maintained primarily in rodents, primates, and birds.   

CHIKV was first identified in Tanzania, East Africa, in the nineteen fifties and has now been found in over one hundred ten countries in Africa, Asia, Europe, and the Americas.  Starting in two thousand four, there have been more outbreaks because the virus has adapted to spread more easily through Aedes albopictus mosquitoes. Also, global warming allowed the mosquitos to grow in more places, for longer, and bite more people.  

July 2023 was the hottest month in recorded history, and the average global temperature that month was two degrees Fahrenheit above the pre-industrial average. Mosquito behavior, survival, and transmission are affected by climate, and that’s why people in parts of the world that had not had endemic CHIKV are now seeing cases. Huge spikes are found in Brazil, Paraguay, and Argentina.  It’s becoming a problem in India, China, and several African countries.    

Ten years ago, the first locally acquired CHIKV was reported in North America followed by cases reported in Florida and Texas. As the planet warms, we expect other diseases to also spread, but we should act now to slow climate change. 

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Earth’s hottest month: these charts show what happened in July and what comes next
From wilting saguaros in Arizona and hot-tub-like temperatures off the coast of Florida to increased heat-related hospitalizations in Europe and agricultural losses in China, last month felt unusually hot. It was: several teams have now confirmed that July 2023 was the hottest month in recorded history. And there’s more to come.

Chikungunya in the US
Before 2006, chikungunya virus disease was rarely identified in U.S. travelers. During 2006‒2013, studies identified an average of 28 people per year in the United States with positive tests for recent chikungunya virus infection (range 5‒65 per year). All were travelers visiting or returning to the United States from affected areas in Asia, Africa, or the Indian Ocean. In late 2013, the first local transmission of chikungunya virus in the Americas was identified in Caribbean countries and territories. Local transmission means that mosquitoes in the area have been infected with the virus and are spreading it to people.