Residents of Miami Beach were warned on Friday that the “Zika threat continues to grow” after another sample of mosquitoes in the area tested positive for the virus. Miami Beach mayor Philip Levine sent out a notice to all residents and businesses to inform them of the news, noting that the infected mosquitoes were found in the same Miami Beach neighborhood where mosquitoes tested positive for the virus on Sept. 1. Levine said the news only served as a reminder to be “as aggressive as we can be against Zika.” Miami-Dade County mayor Carlos A. Gimenez echoed Levine’s comments, saying Friday that “we must continue our proactive and aggressive approach,” including by conducting aerial spraying. Authorities in Miami Beach began a round of aerial insecticide spraying on Friday, and another round is scheduled for Sunday. As of Sept. 4, authorities had recorded 604 travel-related Zika infections, including 84 pregnant women.