Rubella on the Run
Report says disease nearly eradicated in United States, but pockets remain
TUESDAY, Jan. 22, 2002 (HealthDayNews) -- Rubella is on the verge of joining smallpox and polio on the list of diseases eradicated in the United States, says a new report that doesn't surprise experts, but pleases them nonetheless.
The threat of the disease remains, however, and the demographics have shifted considerably, meaning the public health system needs to revise its stance, says the report, which appears in tomorrow's issue of the Journal of the American Medical Association. Rubella is also known as the German measles.
"We were very much expecting this because [rubella] is basically not seen in U.S.-born individuals that have gone through our childhood program," says Dr. Susan Reef, lead author of the study, who is with the National Immunization Program, part of the Centers for Disease Control and Prevention.
"We were hoping for this," adds Dr. Arnold S. Monto, professor of epidemiology at the School of Public Health at the University of Michigan.
The near-eradication testifies to the success of the childhood rubella vaccination program, which began in 1969. Rubella itself is not a serious illness, but if a pregnant woman passes the disease to her fetus, it can result in miscarriage, stillbirth or congenital rubella syndrome (CRS). That syndrome may bring with it cataracts, hearing impairment, cardiac disease and developmental delay.
"At the point when rubella was controlled, it was the most important single cause of congenital abnormalities," says Monto. The last major outbreak of rubella in the United States occurred in 1964-65. About four to five years after that, enrollment of deaf children in schools spiked.
"It was a major, potentially preventable cause of congenital abnormalities," says Monto.
The study authors analyzed the incidence of rubella and the characteristics of who contracted the disease between 1990 and 1999. In 1969, the year the vaccine was introduced, there were 57,600 cases of rubella and 62 cases of CRS. Between 1990 and 1999, the median number of rubella cases reported annually was 232. For the decade, 117 cases of CRS were reported. Over the course of ten years, the incidence of rubella decreased dramatically, from 0.45 cases per 100,000 people to 0.1 per 100,000.
When it does occur today, rubella mainly strikes foreign-born Hispanic adults who have not been vaccinated or who don't know whether they've been vaccinated. The mothers of babies born with CRS also tend to be Hispanic and foreign-born. These outbreaks do not pose a threat to the general population, most of whom have been vaccinated.
The disease also appears to be striking more adults and fewer children. In 1990, children under the age of 15 were more likely to contract the disease. By mid-decade, that number fell while the number of cases in people aged 15 to 44 rose. Since 1992, more than half of rubella cases occurred in women of childbearing age.
As of January 2001, 44 of 47 countries in the Americas had childhood rubella vaccination programs, a development that should go a long way towards eradicating the disease completely in the Western Hemisphere. In the meantime, vaccination is still the biggest guarantee in the United States.
"I think the most important thing is to maintain high immunity levels in our populations, which means we need to continue to have high coverage in children," says Reef. "And for those at high risk of developing rubella, we need to educate them that they may be susceptible and may need to be vaccinated."
What To Do
Physicians recommend that the rubella vaccine (administered with measles and mumps vaccines in the MMR vaccine) be given to children between 12 and 15 months of age, and again before they enter kindergarten.