Though summer is over, the warmth that invites mosquitoes remains for many parts of the U.S. These high temperatures continue to pose a problem for states and territories facing the Zika virus.

There have been 4,016 Zika cases in the United States and a staggering 27,402 in U.S. territories like American Samoa, Puerto Rico and the U.S. Virgin Islands. The disease is most dangerous to pregnant women for its ability to cause brain defects in fetuses, including microcephaly, which can induce seizures, developmental delays and vision or hearing loss post-labor.

The possibilty of eradicating the virus does not seem likely in the near future. The Centers for Disease Control and Prevention Director Thomas Frieden said, at the CityLab 2016 conference in Miami yesterday (October 25), that the disease has proven to be “not controllable with current technologies,” reports USA TODAY. “We will see this become endemic in the hemisphere.”

Miami, where CityLab was held, has been a hotspot for local transmission of the virus. Two new, non-travel related Zika cases were identified in the city yesterday. The Miami Herald reports that Frieden told conference audience members that “the mosquito-borne virus is more widespread than Florida health officials have reported.”

(H/t USA TODAY, Miami Herald)