Dengue fever map: Where the mosquito-driven illness is validated, spreading fastest

( NEXSTAR)-- Federal health authorities alerted physicians around the U.S. today to look out for indications clients might have dengue fever, a virus spread by mosquitoes that's rising worldwide. Cases in the U.S. are three times higher than this time last year.

The majority of the cases in the U.S. are in people who recently took a trip abroad to regions where dengue is spreading rapidly. Just one state up until now, Florida, has proof of regional transmission, the Centers for Disease Control and Prevention says. U.S. areas Puerto Rico and the Virgin Islands are also seeing local spread of the disease.

Cases connected with travel are more typical. Thirty-eight states plus D.C. have reported at least one case of dengue fever this year.

The map listed below programs which states have and have actually not reported verified cases of dengue to the CDC: gray shows no known cases, pale green indicates just one to 4 validated cases, teal represents 5 to 49, and blue is for states with 49 to 250 cases of dengue fever.

Florida has 191 verified cases, New York has 134 and Massachusetts has 50, according to CDC tracking. At least 2,241 cases have been confirmed nationwide.

( Map: CDC).

For an interactive version of the map above, examine the CDC's website here.

In a health alert Tuesday, the Centers for Disease Control and Prevention encouraged physicians to understand the symptoms, ask concerns about where patients just recently took a trip, and consider purchasing dengue tests when appropriate.

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The virus is spreading fastest in tropical, warm nations, where warm weather mosquitoes that bring the disease thrive. These mosquitoes are expanding their geographical variety due to the fact that of environment change, professionals say.

In the very first four months of this year, 7.9 million cases and 4,000 deaths have actually been reported, according to the World Health Organization.( Map: CDC).

About 1 in 4 dengue fevers are symptomatic, the CDC says. Signs, if they do happen, appear typically five to 7 days after infection. People often feel fever and other flu-like symptoms such as queasiness, throwing up, aches, rashes, joint and bone discomfort, and headaches.

Serious cases can cause major bleeding, shock and death. There is no extensively readily available medication for dealing with dengue infections.

The Associated Press contributed to this report.