The number of confirmed cases of dengue fever on the Big Island rose to 122 on Wednesday, from 117 the day before.
The figure means this outbreak is now as big as an outbreak in 2001, previously the largest the state had experienced.
The Hawaii Department of Health confirmed that there were five new cases on the island.
Of the confirmed cases, 106 are Hawaii Island residents and 29 are minors.
The number ties with Hawaii’s last major dengue fever outbreak, which was on Maui in 2001.
In all, 122 confirmed cases were reported, beginning in a rural region of the island and then centering in areas with thick vegetation and heavy precipitation. According to the Centers for Disease Control and Prevention, the strain was likely imported by travelers from French Polynesia.
The most recent locally-acquired dengue fever outbreak in Hawaii was in 2011, when five people on Oahu contracted the illness.
Dengue fever is transmitted to humans when they are bit by infected mosquitoes. The symptoms usually include a sudden onset of fever, severe headaches, rash and eye, joint and muscle pain.
There was one recent case of illness on Oahu, but it was not locally transmitted. No other locally-acquired dengue fever cases have been reported on any other islands.
The new total comes as a Centers for Disease Control and Prevention team is in Honolulu to work with the state on efforts to stem the outbreak.