Boston, MA (AHN)-After four people in a downtown office tower were diagnosed with the highly infectious disease, Boston health officials worked to contain the city's first outbreak of measles in seven years.

The Boston Public Health Commission opened a second emergency health clinic after it became known that hundreds of workers may be at risk of developing measles. An initial emergency clinic was set up on May 11 after the first case emerged.

According to the Reuters report, the four who were diagnosed with the disease all worked at Investors Bank and Trust, a financial services firm. Three of the workers caught the disease from a contract worker who recently traveled from India.

John Auerbach, Boston Public Health Commission's executive director, says hundreds of workers at Investors Bank & Trust had received vaccinations to prevent an outbreak, saying while measles is very rare, "there are still pockets of the population that aren't immunized."

Meanwhile, John Riley, head of marketing and communications at Investors Bank & Trust-a firm with 1,500 employees in Boston-says all four workers had recovered.