An outbreak of measles this winter that originated at Disneyland in Anaheim, California, sparked a backlash among Americans incredulous that pockets of children and adults were not being vaccinated. Government health officials reminded the public that repeated research had shown the vaccine against the virus was safe and effective. Until 2014, measles had been declared eradicated for more than a decade thanks to vaccine policies that mandated children get their shots.

Further proof of the effectiveness of vaccines came to light Wednesday, when the World Health Organization announced that another illness has been eradicated that also is prevented by the vaccine that shields from measles: Rubella, sometimes called German measles, has been declared eliminated in North and South America – encompassing 45 countries and territories.

Before vaccination efforts, up to 20,000 children were born with congenital rubella syndrome each year in Latin America and the Caribbean. In the U.S., 20,000 infants were born with congenital rubella syndrome during the last outbreak, which occurred from 1964 to 1965. In most people, the virus leads to a rash, joint pain and swollen glands. But it is particularly dangerous to pregnant women, causing miscarriage or birth defects such as blindness, deafness or congenital heart defects.

Dr. Paul Offit, professor in the division of infectious diseases and the director of the Vaccine Education Center at the Children’s Hospital of Philadelphia, says he doesn’t think people fully understand how dangerous rubella was.

“It created a lot of anxiety with mothers,” he says. “[The vaccine] was a breakthrough. Before that, there were 5,000 cases of miscarriages a year in the early 1960s and before.”

Dr. Stanley Plotkin, who developed the vaccine against rubella in the 1960s, says he was driven by the effect the virus had on mothers and their babies. Thousands of women underwent induced abortions out of fear they might deliver children born with the effects of rubella, he says, adding: “That was certainly an inspiration to try to prevent the disease.”

Though rubella was declared eliminated in the U.S. in 2005, Wednesday’s announcement showed that immunization strategies were effective in neighboring countries, resulting in no origination of the virus in more than five years, according to WHO’s Pan American Health Organization.

Rubella continues to spread in other regions, resulting in 110,000 infants born with congenital rubella syndrome worldwide each year. Plotkin recalls that when he was a medical resident, there was a major outbreak of rubella in London that spread to the U.S.

Even today, Europe still does not have vaccination rates as high as in the U.S. because there isn’t as much enforcement, he says. “They try to take it routine as much as possible, but there are lapses,” he says.

In the Americas, imported cases still occur but are isolated. Public health officials consider a disease eliminated if it hasn’t originated a specific region for three years.

“There’s no person-to-person spread in American children,” Offit explains. “It doesn’t mean the disease doesn’t come into the country.”

Rubella spreads when an infected person coughs or sneezes, and people without symptoms are contagious. There is no antiviral treatment like there is for the flu, but one dose of vaccine is at least 90 percent effective at warding off rubella, according to the Immunization Action Coalition. As with mumps or measles, anyone who catches the virus later becomes immune against it.

Now, rubella and congenital rubella syndrome – the type that affects a developing fetus – are the third and fourth vaccine-preventable diseases to be eliminated from the Americas, following the eradication of smallpox in 1971 and the elimination of polio in 1994.



“All four achievements prove the value of immunization and how important it is to make vaccines available even to the remotest corners of our hemisphere,” Carissa Etienne, director of the Pan American Health Organization, said in a statement.

These elimination results are part of a 15-year effort to immunize people against rubella, through use of the measles-mumps-rubella vaccine, called the MMR vaccine, which was lumped into one vaccine beginning in 1971.

Though there are some religious or personal exceptions in the U.S. by state, most children are required to be vaccinated before they enter kindergarten. As a result, MMR vaccination rates across the U.S. are high, at or above 94 percent among children enrolled in kindergarten. When narrowed by state, however, the rates vary significantly, from 82 percent in Colorado to 98 percent in Mississippi.

Some parents forgo vaccinations because of a belief that the measles portion of the vaccine causes autism. The study that first implied that, however, has been discredited multiple times and the author who led it lost his medical license.

Still, vaccination gaps contributed to the outbreak of this year’s measles outbreak, which has spread to 166 people in 19 states. These figures are concerning to public health officials, because the disease had been eliminated in 2000.

Measles, however, is also more contagious than mumps or rubella. A person who exposes himself or herself to others on a typical day has a risk of spreading it to 18 people, while rubella could spread to about seven others, says Offit. To achieve herd immunity, or the percentage of people who need to be vaccinated to avoid a spread, up to 94 percent of people need to be vaccinated against measles. For rubella, 85 percent vaccination is effective, he explains.

Rubella is particularly dangerous to women of childbearing age. “I think the parents who don’t give the vaccine to their children are making a big mistake for unfound reasons,” Plotkin says. A female child who grows up to become pregnant is relying on “the good graces of people around her who have been vaccinated,” he says.

Etinne said in a statement that the fight against rubella had taken more than 15 years. “It has paid off with what I believe will be one of the most important Pan American public health achievements of the 21st century,” she said in a statement. “Now it’s time to roll up our sleeves and finish the job of eliminating measles as well.”