If you’re 16 or older in Illinois you will officially be eligible for a COVID-19 vaccine starting Monday, and now you’ll be able to try to get an appointment in suburban Cook County.

The county announced Thursday that it would join the state in expanding vaccine eligibility to include all adults 16 and over, regardless of their age, health condition or job type. Cook County joins all other 101 Illinois counties expanding vaccine eligibility next week.

“As of April 12, we’re taking another step toward normalcy,” Cook County Board President Toni Preckwinkle said at a Thursday news conference. “And while we’re excited to take these steps, I want to make sure that we continue to set clear expectations, demand continues to outweigh supply of the vaccine. So I join my colleagues in asking for your continued patience.”

That’s why the city of Chicago won’t expand its eligibility until a week later, on April 19, the date President Joe Biden has set for universal adult eligibility nationwide. City officials have cited insufficient vaccine supply in their decision to wait, and have repeatedly said they need the state to direct more vaccine supply to the northeast region of Illinois.

That means starting Monday, all Illinois residents 16 and older — including those who live in Chicago — will be eligible to get a shot under the state’s guidelines. But Chicagoans who don’t qualify for a vaccine under 1a, 1b, or 1c (the city’s current eligible phases) will have to travel outside of the city for a shot until April 19.

At a news conference Thursday, Gov. JB Pritzker said the state will open up new appointments at state-run sites in Cook and the collar counties.

“In an effort to prioritize our highest-demand counties, I’m proud to announce that as we move to universal adult eligibility, we are opening up 150,000 new, first-dose appointments, next week alone, for our 11 state-supported mass vaccination operations in Cook and the collar counties and the area pharmacies open to any Illinois resident.”

Pritzker stressed that Chicagoans, too, are welcome to sign up for appointments at state-run mass vaccination sites.

Pritzker acknowledged the importance of vaccinating high-risk people first, but emphasized that the move to open eligibility is to stop the spread and creation of new, contagious COVID-19 variants that are circulating among young people in Illinois.

“It is important that we begin to address the whole population because the danger of the new variants spreading means that we want every dose to get into arms as soon as humanly possible,” Pritzker said. “The vaccine is the best weapon against the variants, and it’s the fastest ticket back to normal life.”

Pritzker said Thursday the state has administered 6.7 million doses of the vaccine; 73% of seniors have had at least one dose of the vaccine; 42% of those 16 and over have had one dose; and nearly 25% of the adult population has been fully vaccinated.

As officials celebrated the progress the state, nation and the world has seen in vaccination efforts, Dr. Ngozi Ezike, Illinois’ public health director, reiterated that cases are on the rise.

“On March 15, we reported 782 cases,” Ezike said. “Yesterday, nearly 4,000 new cases. So yes we have a vaccine and we are elated about that, but it doesn’t mean that this pandemic is completely over. … This resurgence is here, and until we have better herd immunity, we will continue with this layered public health, measured response involving wearing masks, washing your hands.”

Mariah Woelfel is a general assignment reporter at WBEZ. You can follow her on Twitter at @MariahWoelfel.