A Texas woman died last October from a rare complication of dengue fever, a reminder that the virus has spread to parts of the southern U.S., federal health officials said Thursday.
Her illness was initially misdiagnosed as West Nile Virus, another mosquito-borne illness recently imported into the U.S., the Centers for Disease Control and Prevention reports. It’s the third known death from dengue acquired in the United States in 10 years, the CDC says.
The 63-year-old woman had traveled to Santa Fe in New Mexico and it’s possible she was bitten by a mosquito carrying dengue there, CDC experts said. Dengue cases in the U.S. are usually imported, but in this case the patient hadn’t traveled to anywhere the virus is entrenched.
The World Health Organization estimates that 50 to 100 million people are infected with dengue each year. Most get a fairly mild fever but 500,000 develop hemorrhagic disease, which includes internal bleeding, and 22,000 die.
In this case the woman developed hemophagocytic lymphohistiocytosis, a serious type of inflammation.
Her first symptoms were typical flu-like complaints — fatigue, headache, leg cramps, fever, and chills. She tested positive for West Nile virus, but the CDC says it’s possible that antibodies her body developed to fight dengue cross-reacted with the West Nile test.
Because people with flu-like illness so rarely get tested for anything, the CDC says no one knows how common dengue really is in the United States.
There’s no specific treatment for either West Nile virus or for dengue, but the CDC says doctors need to be alert and that people traveling to areas with a risk of dengue should use bug repellent, stay inside with screens on windows and doors and empty water containers where mosquitoes breed.
Note: the mosquitoes that carry dengue cannot tolerate the cold climate in Canada or the northern US.