According to U.S. health officials, a record high rate of 81 percent of toddlers 19 months to 3 years old are now getting vaccinated with the full recommended series.
The Centers for Disease Control and Prevention (CDC) says this figure is up from 79.4 percent last year and continues a steady upward climb.
CDC Director Dr. Julie Gerberding says the figures illustrate the tremendous progress made in preventing what were once common childhood diseases, and more importantly, that parents have high levels of confidence in vaccination recommendations.
There has been pressure felt by U.S. health officials from a few small but increasingly vocal groups who question the safety of childhood vaccines.
The first targets were the combined measles, mumps and rubella or whooping cough vaccine, and they are now suggesting that a mercury-based preservative called thimerosal once used in vaccines causes, among other things, autism.
Despite numerous official reports absolving vaccines from causing damage to young children, the activists have won the backing of some members of Congress.
But fortunately the controversy does not appear to have affected overall vaccination rates.
The CDC says that in 2004, coverage for the 4:3:1:3:3 series, which includes four doses of Diphtheria, Tetanus and Pertussis (DTaP), three or more doses of polio vaccine, one or more doses of measles-containing vaccine, three or more doses of Hib vaccine which can prevent meningitis and pneumonia, and three doses of hepatitis B vaccine, increased to 80.9 percent, compared to 79.4 percent in 2003.
The CDC's National Immunization Survey also found that most children are also getting newer vaccines against chickenpox and pneumococcal disease.