NEW BEDFORD — Southcoast Health is encouraging area residents to defend themselves against measles.

A nationwide outbreak has seen over 700 confirmed cases of the virus this year. Dr. Robert Caldas, Chief Medical Officer of Southcoast Hospitals Group, says the cause for the spike in measles cases can be traced back to people who voluntarily decline the vaccine.

"We're losing some of the herd protection that we get from having a lot of people immunized," Dr. Caldas said on The Phil Paleologos Show. "Now there are people who are vulnerable, and they travel abroad into areas where there are outbreaks of measles and unknowingly bring it back to the U.S."

Dr. Caldas says the U.S. typically sees only about 100-200 cases of measles in a given year.

Dr. Caldas says if people are unsure if they have received the measles vaccination, they should contact their primary care physician.

"They will find out quickly whether or not they've already been immunized. If they haven't, then those vaccines are routine vaccines that are supplied by the state and are readily available."