Broward County Health Department and Mosquito Control officials on Monday issued an alert after confirming a human case of locally acquired dengue fever in the county.

Dengue is a viral disease that is primarily spread to people through bites from infected Aedes species mosquitoes, which are the same mosquitoes that spread Zika and chikungunya viruses, according to the U.S. Centers for Disease Control and Prevention. Symptoms usually begin within two weeks and can last nearly three weeks, including aches and pains, nausea and rashes.

So far this year, more than 250 cases of locally acquired dengue have been reported throughout the state in at least seven counties, according to the latest Florida Department of Health Arbovirus Surveillance report.

Florida’s current outbreak appears to be the largest in the country in several decades, the Associated Press reported.

Dengue fever and other mosquito-borne illnesses surging in Florida

The confirmed case in Broward County was locally acquired, meaning the person was infected after being bitten in Florida and not while traveling abroad. Palm Beach County and Miami-Dade County also have recorded locally acquired cases, the department of health report shows.

In Broward County, at least 20 other cases this year were reported in people who traveled to “a dengue-endemic area” in the two weeks before symptoms began.

“DOH-Broward and Broward County Mosquito Control are coordinating surveillance, prevention, and control efforts,” the department said in its advisory Monday.

The vast majority of locally-acquired cases in Florida, more than 200 of the total, have been recorded in Hillsborough County on the state’s west coast, where a state of local emergency is in place until Thursday. The Tampa Bay Times reported that a Hillsborough County woman who died last month was the first known person to die from dengue fever in the state this year.

Broward Department of Health officials offered the following tips for prevention:

Wear protective, loose-fitting, long-sleeved clothes to prevent from mosquito bites.
Use insect repellents that are registered by the U.S. Environmental Protection Agency.
Repair any damaged screening on windows and doors and drain any collected water from cans, buckets or containers to control mosquitoes indoors and outdoors.