Florida has recorded 190 locally acquired dengue fever cases across six counties, according to the Florida Department of Health’s latest surveillance data. Pasco County declared a local state of emergency on Sept. 23, followed by Pinellas and Hillsborough counties the following day. The emergency declarations are expected to remain in place for about a week.

Pinellas County officials said 179 confirmed dengue cases had been identified across the three-county Tampa Bay area in the latest report, including seven in Pinellas County. Local mosquito-control teams have increased surveillance, public education and treatment efforts in areas affected by the outbreak.

The Centers for Disease Control and Prevention has also recorded 392 dengue cases in Florida that may have been associated with travel as of Tuesday, far more than any other state. California had the next-highest total, with 31 cases.

Dengue is spread primarily by the Aedes aegypti mosquito, which thrives in Florida’s warm climate and can breed in relatively small amounts of standing water. Health officials say several factors may be contributing to the increase, including travel and environmental changes following Hurricanes Helene and Milton.

Dengue is common in parts of Latin America, the Caribbean, Africa and Southeast Asia, meaning travelers can become infected outside the United States and later bring the virus back with them. The CDC says most dengue cases reported in the continental United States occur among people who were infected while traveling abroad.

The virus can cause fever, severe headaches, muscle and joint pain, nausea, vomiting and rash. In more serious cases, dengue can result in internal bleeding, shock and death.

Authorities are responding with aggressive mosquito-control measures. Hillsborough County has used trucks and helicopters to spray insecticide and has worked with neighboring counties on aerial applications of larvicide. Officials are also targeting locations such as tire shops, where small amounts of standing water can provide breeding sites for mosquitoes.

Local officials are urging residents to reduce standing water around their homes and take precautions to avoid mosquito bites as the counties work to contain the outbreak.