The Los Angeles area is seeing more cases of people with dengue fever without traveling outside the United States, a year after the first such case was reported in California.

While Los Angeles County is reporting three locally acquired cases of dengue this year -- which is rare for the region -- there have been at least 3,085 cases nationally of locally acquired virus so far this year,

The Los Angeles Department of Public Health said it’s investigating two additional cases of locally acquired dengue in residents of Baldwin Park. Last Monday, officials had reported the first confirmed case of locally acquired dengue also in Baldwin Park.

LA County health officials warned about an "unprecedented" cluster of dengue cases after two more people in Baldwin Park tested positive.

A cluster of three cases in Baldwin Park “is an unprecedented number of locally transmitted cases for a region where dengue has not previously been transmitted by mosquitoes.”

According to the health department, none of the patients had any history of traveling to areas where dengue is endemic.