(CNN)– Two health experts are flagging concerns that a yellow fever outbreak in rural Brazil could spread to the United States.
They raised their concerns in an essay published in the New England Journal of Medicine.
One of the experts wrote that the likelihood of a US outbreak is low but that travel-related cases could occur, with local transmission in warmer areas like the gulf coast.
The fear is that the disease could spread like the Zika virus – which also originated in Brazil.
Like Zika, the virus is spread by mosquitos.
As of march second, yellow fever had killed an estimated 220 people, according to the pan American Health Organization.