(ABC NEWS) -- While children in the U.S. are often required to be current on their vaccinations or receive a special waiver in order to attend public school, there is no requirement for adult vaccinations, despite several diseases that continue to present dangers. Public health officials have long struggled to bring adults in the U.S. up to date on vaccines.
"Vaccinations are not just for kids," Dr. William Schaffner, an infectious disease expert at Vanderbilt University Medical Center, told ABC News. "There are any number of vaccines that are targeted to adults. We can do a much better job to deliver these vaccines."
Officials from the U.S. Centers for Disease Control and Prevention's advisory committee on immunization practices released new recommendations for hepatitis B, influenza and HPV vaccines today as part of its annual vaccination guidelines.
Among the possible reasons the report cited for low vaccination coverage among adults in the U.S. were "competing priorities with management of patients' acute and chronic health conditions, lower prioritization of immunization for adults compared with other preventive services, and financial barriers to providing vaccination services to adults."
Not surprisingly, adults who had health insurance were more likely to be up to date on their vaccination coverage. Immunization rates for people with health insurance were two to five times those for people without health insurance.
The CDC found that another barrier to vaccine coverage could be physicians themselves. It reported that approximately 25 percent of internists felt age-based vaccination recommendations for adults were difficult to follow. Additionally, 29 percent reported that vaccine recommendations based on medical condition were difficult to follow.
The advisory committee recommends using amplifiers — including patient reminders, recalling patients who have missing vaccines and having alerts in electronic medical records — to improve immunization coverage for adults.
Schaffner said he hoped additional funding to help adults afford vaccinations, especially if they don't have health insurance, could be implemented on a national level in order to improve vaccination rates.
"The population, with the exception of the influenza vaccine, doesn't think about vaccines for adults very often," he said. "These are important to you, and most of these are communicable diseases."
Among the changes to the CDC's recommendations this year are updates on administering the hepatitis B, HPV and flu vaccines. For the HPV vaccine, the CDC now recommends only two doses five months apart, if started before age 15. If the vaccination is started after age 15, then three doses are recommended.
To protect against meningitis, healthy adults are now recommended to have only two — not three — doses of the serotype B meningitis vaccine. However, three doses are recommended in cases of meningitis outbreaks or if a person is at increased risk for contracting the disease.
For those with chronic liver disease or liver enzymes that are at worrying levels, the CDC now recommends receiving the hepatitis B vaccine to protect the liver from infection.
Finally, the CDC recommends using the common injection flu vaccine, not the nasal mist, which was found to be less effective in studies.
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