Most kindergartners are up to date with their vaccines, but federal immunization goals nevertheless remain unmet, the CDC says.

According to a CDC report, the average number of kids who have been vaccinated for measles, mumps, and rubella is 94.8%. Health officials have set their target at greater than 95%.

"Coverage is not the way it should be," says Jaime Deville, MD. Deville is a professor of pediatric infectious diseases at UCLA's Mattel Children's Hospital. He reviewed the report for WebMD.

"This report really confirms what's already well known," he says.

The report's authors point out that vaccine rates vary significantly from state to state. The five states that are doing the best job of vaccinating kids against measles, mumps, and rubella (MMR) are:

1. Texas 99.3%
2. Mississippi 99.2%
3. Nebraska 99%
4. Maryland 98.7%
5. Louisiana 98.1%

The five states that need the most improvement when it comes to MMR vaccines are:

1. Colorado 86.8%
2. Pennsylvania 86.9%
3. Kansas 88.2%
4. Idaho 89.2%
5. North Dakota 90.6% 

Tetanus, Diphtheria, and Other Vaccines

The report also tallies vaccine numbers for tetanus, diphtheria, acellular pertussis (whooping cough), polio, hepatitis B, and varicella (chickenpox).

Forty seven states, the District of Columbia, and five other areas reported their vaccine numbers. The city of Houston submitted its own figures, which were the highest reported, at 99.5% for MMR. Figures for Wyoming, New Hampshire, and New Jersey were not available.

California, the state where Deville teaches and practices, met the 95% goal for only two of the vaccines: chickenpox and hepatitis B.

"Our coverage is really not ideal," says Deville. He says the number of children in his state who were granted exemptions from vaccines for medical, religious, or philosophical reasons is too high for comfort.

"We see there are 12,000 out of the half million kindergarten age kids here," says Deville. "That's a sizable percentage that right off the bat won't be vaccinated."

Exemptions From Immunization

Overall, according to the report, 1.5% of children were granted exemptions from vaccinations. That figure varied dramatically from state to state. Mississippi, which does not allow religious or philosophical exemptions, had an exemption rate below 0.1%, the lowest number in the country. Alaska granted exemptions to 7% of its children. Arkansas reported the largest increase in exemptions from the previous year; Nebraska reported the steepest decline.

For the most part, the percentages reported reflect statewide averages. However, the report's authors point out the need to focus on local rates of immunization that might get overlooked when focusing on the big picture.

"Since exemptions cluster geographically, there might be smaller areas and schools where low levels of immunization could sustain ongoing measles transmission after importation from other countries," the report states.

Measles Still Threatens Children's Health

While the current level of vaccine coverage is likely to prevent any major outbreaks of measles, Deville says, measles -- and other diseases for which vaccines are available -- should be on parents' radar.

"We've been seeing only about 50 cases a year for the past several years, but that number has begun to creep up," he says.

In 2011, 222 cases of measles were reported to the CDC, the highest number in 15 years. Most of those cases, the report says, were brought here from outside the U.S.

"Measles," Deville says, "is one of the most contagious diseases, with significant complications and mortality. We don't want to deal with it again."

Deville points to recent whooping cough outbreaks as examples of why parents need to make sure their kids are properly vaccinated. It's easy to think there is little to worry about when such diseases are rarely seen these days, he says. That's a mistake.

"Just because we don't see them doesn't mean they no longer exist," Deville says. "These diseases are not gone."

SOURCES: Morbidity and Mortality Weekly Report, Aug. 24, 2012.Jaime Deville, MD, professor of pediatric infectious diseases, Mattel Children's Hospital, UCLA.

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