NEW YORK (Reuters Health):

Many new immigrants and refugees to the United States and Canada are susceptible to measles, mumps and rubella. In particular, immigrant women show lower rates of immunity to rubella than immigrant men.

These groups "may benefit from targeted vaccination programmes," the authors suggest in their study, published in the Annals of Internal Medicine.

Dr. Christina Greenaway of Jewish General Hospital, Montreal, and her colleagues conducted a study of 1,480 adult immigrants and refugees between October 2002 and December 2004 to assess their immunity to measles, mumps and rubella.

Women more susceptible

Thirty-six per cent of the immigrants were susceptible to at least one of these three infections, the team found. Women were twice as likely as men to be immune to measles.

However, women were 30 per cent more likely to be susceptible to rubella than men. Rubella, also referred to as German measles, is of particular concern in women because infection during pregnancy, especially in the first trimester, is associated with birth defects.

"In light of recent rubella and mumps outbreaks, our findings highlight the need to keep measles, mumps and rubella vaccinations up to a date in foreign-born individuals to protect susceptible persons and to prevent outbreaks," the researchers write. They add that "susceptible immigrants may import these diseases after trips to endemic countries to visit friends and relatives."

While all immigrants are required to have up-to-date vaccinations, "gaps in vaccination coverage remain ... because some groups, such as asylum seekers, refugees and adoptees, are excluded and because no systematic mechanism verifies vaccine doses," Greenaway and colleagues note.

They call for the development and implementation of strategies to keep vaccinations up to date in foreign-born individuals.