Study shows vaccinations of U.S. children declined after autism controversy

New research has shown that fewer parents in the United States vaccinated their children after hearing about a now refuted link between the MMR vaccine and autism.

The study, conducted by the University of Cincinnati, found that the MMR-autism controversy that followed the release of a 1998 study in the British medical journal the Lancet led to a decline in parents vaccinating their children with the MMR by approximately two percent over the next two years, according to ScienceDaily.com.

The drop persisted after following studies thoroughly refuted the link between the MMR and autism.

Lenisa Chang, an assistant professor of economics at UC's college of business, examined data from the National Immunization Survey from 1995 through 2006 in order to gauge how parents responded to the controversy.

Chang found that the higher a mother's education level, the less likely she was to allow her child to receive the MMR vaccination. After epidemiological studies refuted the MMR-autism link, the difference in usage by mother's education level persisted and became more pronounced from 2003-2006.

The study also suggests there was a spillover effect from the controversy that affected other vaccine uptake rates.

"The spillover effect I find on other vaccines such as polio and, to a lesser degree DTP (diphtheria, tetanus and pertussis), could be partially ascribed to general safety concerns toward all vaccines that stemmed from the MMR controversy, but other factors might be at play as well," Chang said, ScienceDaily.com reports.