AURORA, Ill. (WLS) -- A sign that reads "face covering required regardless of vaccination status" can be seen outside Aurora's City Hall, as well as all other government buildings in the west suburban town.
As it's partially in four counties, including two that are now considered areas of high transmission by the Centers for Disease Control and Prevention, Aurora's population seems to be taking the guidance seriously, with many more people seen wearing masks than in previous days.
It is the same guidance that is now being given to residents of Lake County, which on Saturday made the jump to a region of high transmission.
"COVID fatigue is definitely real, and we understand that, but it really is the best path forward toward ending the pandemic," said Emily Young with the Lake County Public Health Department. "So we strongly encourage all residents and individuals to follow CDC guidance while that is in place, and right now that includes masking indoors."
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With the addition of Lake, there are now four counties in Chicago's metropolitan area that are considered high COVID transmission areas.
A high level means the detection of at least 100 cases per 100,000 people over a seven-day period.
DuPage and McHenry counties were at the same risk level just Friday, but have since joined Cook and Kane counties at substantial risk.
"The majority of cases are happening in individuals who are unvaccinated. So the best prevention measure you can take to keep yourself safe is really to get vaccinated," Young said. "That can really help prevent variants before they even start."
COVID-19 cases in Illinois have jumped by 36% over the last week. The state also recorded back-to-back new infections of over 3,000 a day on both Thursday and Friday. That's the first time that has happened since early May.
COVID Illinois: DuPage, McHenry counties drop to lower risk level as Lake raised to 'high'