(NewsNation) — Cases of dengue fever, a viral infection caused by infected mosquitoes, are surging in the U.S. amid warnings from federal health officials to be alert for the disease.
According to the World Health Organization, there are an estimated 100 to 400 million infections each year worldwide, and it’s usually found in tropical and subtropical climates.
It can have mild or no symptoms but can be fatal in severe cases. Most people get better in one to two weeks.
Cases of dengue fever in the U.S. are three times higher than this time last year.
Most cases in the U.S. have been found in people who recently traveled abroad to regions where it is quickly spreading. Florida is the only state with local transmission so far, according to the Centers for Disease Control and Prevention.
Thirty-eight states plus D.C. have reported at least one case, with Florida, New York and Massachusetts reporting the most cases.
The virus spreads fastest in warm, tropical countries. Last year, 6.6 million cases were reported worldwide. In the first four months of this year, 7.9 million cases have been reported according to the WHO.
Dengue fever can cause fevers, headaches and nausea in mild cases, and symptoms usually last from two to seven days.
Those who are infected a second time are at risk for more severe symptoms such as persistent vomiting, bleeding gums or nose and severe abdominal pain.
Federal health officials have urged doctors to be alert for cases as the disease spreads.
Most cases of dengue fever are treated at home with pain medicine, as there is no specific treatment. However, severe cases often require hospitalization.
According to the CDC, a vaccine is recommended for children ages 9 to 16 who have contracted the infection and live in areas where it’s common.