By Mugo Odigwe

CHICAGO (CBS)– As Chicago joins the rest of the state in making the COVID-19 vaccine available to everyone age 16 and up on Monday, city officials said half of all adults in the city have received at least one dose.

The city is now in Phase 2 of vaccinations and United Center is one of at least 14 places you can try to book an appointment.

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For those who are 16 or 17 years old, there’s extra challenge in booking an appointment.

According to the Chicago Department of Public Heath, anyone under 18 must have a parent or guardian book vaccine appointments for them. Also, Pfizer is the only vaccine that’s been approved for 16- or 17-year-olds.

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The city is hoping entering Phase 2 on Monday will increase the number of people getting vaccinated.

The mayor’s office said 50% of Chicago adults — more than 1 million people — have now received a first dose of the vaccine, and about four times as many Chicago residents have received a vaccine as have ever been diagnosed with the virus.

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You can sign up for vaccine appointments in the city at zocdoc.com/vaccine. You can also call the city’s help line at 312-746-4835.