Parents in Oregon refusing vaccines sharply increases

The number of parents delaying infant vaccinations has risen sharply in Oregon, raising experts' fears of potential outbreaks.

A recent study published in the journal Pediatrics found that between 2006 and 2009, the number of children consistently delaying vaccinations in the Portland area increased more than three times, according to

In 2009, approximately 9.5 percent of Portland-area parents consistently did not follow the recommended vaccine schedule for children from birth to nine months of age.

Parents were considered "shot limiters" if they would not allow their children to be vaccinated with more than one or two shots at a time. The study noted that many who limit shots may be following an alternative schedule and plan to eventually complete the schedule, many do not follow through.

"There is no benefit to spacing out shots or getting fewer shots per visit," study author Steve Robison, an epidemiologist with the Oregon Sentinel Immunization Surveillance region, said, reports. "It is a very carefully constructed schedule intended to provide the most benefit when these kids need it."

It remains unknown if the Portland-area trend is reflective of the United States as a whole, but experts said there is likely a large amount of variation throughout the country, depending on factors such as regional attitudes and socioeconomic status.