Two patients at Yale-New Haven Hospital have confirmed cases of the measles on Sunday.
According to the hospital, within the last two weeks, they have seen two patients with confirmed measles.
It is unclear if the two patients know each other.
Last week, the Connecticut Department of Public Health said the first confirmed case of measles this year was in New Haven County. Health officials said the patient was an adult.
On Monday, the state Department of Health confirmed a second case and said the person is an adult in New Haven County. State officials have not identified any common links between the two cases,
They said both patients have been released.
Measles is highly contagious and can spread quickly if you are not vaccinated.
Vaccination is required to attend schools and colleges in Connecticut, but medical and religious exemptions are available.
Health officials said the measles vaccine is very effective and two doses, which is the standard recommendation, are about 97 percent effective.