A U.S. national health organization is warning that pregnant women should not travel to Japan during the current outbreak of rubella unless protected against the disease through either vaccination or previous infection.
The warning came from the U.S. Centers for Disease Control and Prevention on Monday when the Washington-based institute raised its alert level for the rubella outbreak in Japan to "Level 2," the second-highest of 3 levels.
In Japan, more than 1,100 rubella cases have been reported this year, raising concern about serious health impacts on unborn babies who could be infected with the disease by their mothers during pregnancy.
The contagious disease is often transmitted through coughing and sneezing. Infection in the early stages of pregnancy can cause birth defects, such as hearing impairment, cataracts and heart disorders.