A research study released this week found that young children cared for by the Military Health System are less likely to be adequately vaccinated against preventable diseases than the population at large — even though they have universal access to health care at no charge to their families.
Defense health officials disputed the findings and said they believe military vaccination rates are actually higher than children in the general public, while also acknowledging that they lack concrete documentation to prove that’s true.
The results, set for publication in the May edition of the journal Pediatrics, showed that 72 percent of military children were up-to-date on six vital series of immunizations universally recommended by public health officials. By comparison, 79 percent of kids in the broader public were adequately immunized, according to the researchers’ analysis of data from the CDC’s National Immunization Survey.
The authors, led by Dr. Angela Dunn of the University of California at San Diego, drew no definitive conclusions about why that might be the case, but speculated that several factors that could be at play, including the fact that military members are constantly moving and their children frequently change health providers, making it difficult to track their immunization histories and keep them up to date.
Dr. Amy Costello, the chief of immunization health care operations at the Defense Health Agency, said it’s undoubtedly true that the mobility of the military population puts it at higher potential risk of missing immunizations, but also criticized the study’s methodology, which did not distinguish between children being treated directly by military clinicians and those receiving some other kind of DoD-funded health benefit.
“The way they define military children is a little bit vague,” she said. “So people could fall into that category if they’re the child of an active duty service member, or if they’re the child of a reservist or a guardsman, or the child of a military retiree. They may or might not live with the parent who’s providing the military health benefit, and they may be seen in a mixture of military treatment facilities and private providers. So the definition of ‘military children’ is too broad to draw any conclusions about one system’s vaccination abilities or documentation abilities.”
The authors of the DoD vaccination study were careful to note its limitations — pointing out, for example, that vaccination rates among military children might be underreported in the CDC survey data they relied upon. That’s because it depends, in part, on parents surveyed by phone to remember all of the providers who’ve administered shots to their children, a potentially difficult task for a military family moving frequently within a child’s first few years.
And although DoD does have a loosely-knit electronic health records system, it does not include a central registry of all the immunizations a patient has received. So while a child may have gotten, for example, a measles shot at an Army clinic last year, an Air Force clinician seeing the patient at his parent’s next duty station may not know the child’s immunization history unless it’s delivered to them on paper by the parents.
The authors of the immunization study point to other problems with the military’s capability to track vaccinations, including that it cannot currently track care provided by DoD’s vast network of private-sector providers. The department has already made clear that a better exchange of health data with its private providers is a key objective of the new electronic records system that is now in the procurement stage.
For now though, military clinicians accept the sometimes-incomplete immunization records of the patients they see as a fact of life, and do everything they can to manually construct a vaccination history in order to determine whether a child is up-to-date and build a catch-up immunization plan if necessary, Costello said.
“Sometimes it takes my technician longer to check the patient in than it does for me to see them, just because one of the things they have to do is to build a comprehensive immunization record,” she said. “Any time that people have to work through complicated systems instead of using a potential registry that did that for us, there’s always a risk that something’s going to fall through the cracks. But overall, I think people do a good job of working through the different systems. For those of us who work in military pediatrics, we’re accustomed to it. So if a parent comes in with their child, we ask what their immunization status is and then compare that with what we have in our own database, and if the two don’t match up we check in every place we know to check before we start building an immunization plan for that encounter.”
But while military health officials disputed the study’s findings with regard to overall vaccination rates, they were not able to provide their own definitive statistics.
An initial examination of Air Force data showed that 81 percent of 1-to-3-year old children being seen in that service’s medical treatment facilities were up to date with immunizations. Costello said the actual figure was probably higher, since many Air Force dependents are being cared for in clinics managed by the Army and Navy, and the military lacks the ability to aggregate immunization data across military departments, let alone private-sector providers.
Despite the absence of department-wide data, DoD feels confident that its childhood immunization rates are higher than the general population. As evidence, Costello pointed to indirect measures: during the 2007-12 period covered by the study, the military community did not see any of the disease outbreaks that were present in the general population, and there was only one confirmed case of measles and seven cases of mumps among the 500,000 19-to-35 month-old patients for which he MHS cares.
That’s partially because DoD-operated schools and day care centers are especially strict about requiring immunization records before children are allowed to attend.
“And even though the recent measles outbreak looked big and spread quickly in the general population, among military families, we did not see the number of cases you would expect given that the measles immunization rate was 78 percent in this country,” she said.
In the paper released Monday, the authors acknowledged that the differences they found between samples of military populations and the general public may simply be due to a lack of accurate and complete documentation.
“The NIS relies on caregivers to recall all vaccination providers, and thus limits the use of the NIS to draw firm conclusions in the highly mobile military dependent population,” they wrote. “Immunization registries help document vaccinations and identify which vaccinations are necessary to ensure a child is up to date, which is especially important in populations with multiple providers.”