Long Islanders with certain underlying health conditions will begin getting vaccinated against the coronavirus at state-run facilities Monday.

Appointments are limited, but the state's "Am I Eligible" screening tool updates availability on a rolling basis.

People who have cancer, obesity, heart and neurological conditions, those who are pregnant and others are now eligible for the vaccine. The two state-run sites accepting appointments are at Jones Beach and Stony Brook University Hospital.

Those who want to sign up for an appointment must submit proof of their condition from a doctor's letter, medical evidence of a comorbidity or signed certification.

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"The last thing is something called a signed certificate where you basically attest to the fact that you have one of these comorbidities, and you bring that to the vaccination centers with the other requirements," says Dr. Hugh Cassiere, of North Shore University Hospital. "You need to prove that you either work in New York state or you live in New York state with a valid ID."

As of now, there are no appointments at any of the state-run vaccination sites in New York City or on Long Island until mid-April. If you are in the underlying eligibility category, you can only get it at state sites like Jones Beach and Stony Brook.

State officials tell News 12 that the federal government added people with comorbidities to the 65 and older category without giving more vaccines to the state.