A 77-year-old Burlington County man is the first New Jersey resident to die this year from the mosquito-borne West Nile virus, authorities said Friday.

The death was reported as state and local agencies ramped up efforts to combat the virus, and New Jersey health officials announced that the number of confirmed virus cases had jumped from eight last week to 15.

In Pennsylvania, 16 residents have tested positive for the virus; one, an elderly Luzerne County man, died, officials said.

In the most recent death in New Jersey, the victim developed fever, weakness, and respiratory distress on Aug. 20 and was hospitalized Aug. 26. He died this week. His name and hometown were not released by state health officials.