“Dengue Fever is perfectly natural.”
It is always around someplace. Not worldwide. Not as a “pandemic”.
It’s a tropical disease. By definition, that’s not ‘worldwide’. But mosquitoes - and people - travel.
One thing I forgot in my post 28 is ‘urban cycle’ transmission; which may be why some countries require visitors to be vaccinated to this and Yellow fever. You can’t catch either disease from someone who has it; but a person who has it can be bitten by a mosquito and transfer the virus to the mosquito.
Probably not a big problem for most of the US. But the article referenced ‘the Americas’, not ‘America’. I imagine it is a big problem in parts of Central and South America.