Revised Recommendations for Vaccines are Being Phased In, CDC Report Says

Can vaccines be more useful for some people than for others?

Until now, most physicians have recommended immunizations for all infants and children, as well as for adults at various ages who may have missed shots. But new guidelines that take into account the strength of scientific evidence and individual health to determine whether specific vaccines should be recommended or simply optional for patients are being used in medicine for the first time, a report by the Centers for Disease Control and Prevention says.

The recommendations are based on a framework for evaluating science used by more than 60 major organizations, including the American College of Physicians and the World Health Organization, and will each fall in one of two categories, reflective of evidence that a vaccine is essential to good health. Category A recommendations will include vaccinations considered necessary for all people of a certain age or those who are at an increased risk for contracting a vaccine-preventable disease. Category B recommendations will provide guidance to physicians in the context of individual cases where patients with varying health conditions may or may not benefit from a vaccine.

"Over the years, the science of developing recommendations has changed," said Faruque Ahmed, PhD, a senior scientist at the CDC and a member of the U.S. Department of Health and Human Services' Advisory Committee on Immunization Practices (ACIP), which is leading the effort, in a telephone interview.

The need for updating immunization guidelines stems from the fact that the current language does not always indicate the importance of some vaccines over others. For example, the meningococcal vaccine, which protects against a debilitating and potentially life-threatening disease and can be routinely administered at various stages in a patient's life, may be recommended with the same urgency as the hepatitis B vaccine for older adults with diabetes, for whom that vaccine is not always beneficial.

"In the past, there was no standardized wording, and different words may have been used," said Ahmed. He pointed out the often interchangeable use of phrases such as 'should be given' and 'should be considered' that may lead doctors to interpret instructions differently, depending on their own understanding and preferences.

Ahmed also noted that if recommendations are made more clear, physicians will find them easier to follow and patients will likely gain more confidence in vaccines. To this point, he said some opponents of routine vaccinations have attended his group's meetings over the years and are now supportive of the new approach. SafeMinds, an anti-vaccine advocacy group which promotes the idea that mercury in vaccines is associated with autism, attention deficit disorder, and other neurological impairments, is one of those supporters that have signaled their approval for using evidence-based guidelines.

The first of these instructions, released to physicians last December, urge expanded human papillomavirus (HPV) vaccination for boys and increased, though not routine, hepatitis B immunizations for older adults with diabetes who live in long-term care facilities.

More recent recommendations concern the meningococcal vaccine for infants and the pneumococcal conjugate vaccine for adults. Ahmed said it takes at least a year from the time the guidelines are put into practice to measure their impact on patients and the general population.

The new rules are modeled after an existing system for evaluating scientific evidence, called Grading of Recommendations Assessment, Development and Evaluation (GRADE), in which the evidence backing each intervention is ranked according to type and quality. The recommendation categories are based on those rankings. For example, randomized controlled trials, considered the gold standard in generating scientific evidence, are ranked highest and warrant instructions to doctors that a vaccine "should" be administered, whereas clinical experience without consistent results is used for suggesting that a vaccine "may" benefit patients.

The move toward standardizing recommendations is expected to improve transparency, consistency, and communication in the health care setting and between physicians and their patients.

The news update was published this week in the CDC's Morbidity and Mortality Weekly Report.