While the vast majority of nearly 700 children's doctors surveyed in the study are recommending the vaccine, which protects against bacterial meningitis and other diseases, almost one in three harbors concerns about the cost -- especially if many children they see don't have insurance that covers their shots.
The results are published in the September issue of Pediatrics by researchers at the U-M Health System and the Centers for Disease Control and Prevention.
The findings have immediate implications for the parents of today's toddlers, who may learn they have to pay out of pocket or travel to another location to get the $260, four-shot series that's recommended for all children under age 2 by the Centers for Disease Control and Prevention. Both options are sizable obstacles for many families, and may mean some children don't get vaccinated.
The study results may also foreshadow further problems and "fragmentation" of vaccination practices as other pricey but effective children's vaccines come on the market, says lead author Matthew M. Davis, M.D., MAPP, an assistant professor of pediatrics at the U-M Medical School. Davis is a member of the U-M's Child Health Evaluation and Research Unit, which has a CDC grant to study vaccine issues.
"Vaccines are some of the most cost-effective tools that we have for protecting children's health," Davis emphasizes. "Historically, they have been inexpensive and physicians have been willing to absorb the cost of stocking them or even providing them to underinsured patients. But the cost of Prevnar is eroding physicians' efforts to provide it in their clinics. And in general, vaccines are becoming more like other medications on the market -- ones that are expensive but have profound benefits."
Prevnar's effectiveness is not in question, says Davis: It prevents infections by Streptococcus pneumoniae bacteria that cause tens of thousands of potentially deadly bacterial meningitis and bloodstream infections each year, and untold millions of painful ear infections. That's why parents have clamored to get kids vaccinated with Prevnar since its approval in the year 2000. New CDC data show that despite major shortages, 41 percent of children under age 3 had at least three doses of it by 2002.
But the new study shows that because of Prevnar's unprecedented cost, many doctors -- especially those in smaller practices or who see many children whose insurance doesn't cover Prevnar -- are reluctant to treat it like any other vaccine.
Ironically, Davis notes, children with private insurance are most likely to be affected by this trend.
Such children, whose parents' employer-sponsored insurance plans may not cover Prevnar because of its cost, may be ineligible to receive the federally-funded vaccines provided at no cost to children with Medicaid, no insurance coverage or other qualifications under the CDC's Vaccines for Children program. VFC vaccines can be given at doctors' offices or public clinics.
Some states supplement VFC's coverage by purchasing vaccine that doctors can administer to children in private insurance plans that don't cover all vaccines, or to all children regardless of insurance status. But, Davis says, the high cost of Prevnar appears to be a hurdle for some states in the current budget crunch, and they have left it off their lists of subsidized vaccines.
This "patchwork" system of vaccine coverage was the subject of a recent Institute of Medicine report that called for more uniform coverage, partly on the basis of evidence from the U-M Child Health Evaluation and Research Unit, led by study co-author Gary Freed, M.D., MPH. The IOM report also advised Congress to require private insurance plans cover all CDC-recommended childhood vaccines, with a subsidy from the federal government.
For now, though, Davis recommends that parents with private insurance who have children who meet CDC recommendations for Prevnar call their insurers to ask whether the vaccine is covered.
The CDC recommends Prevnar be given to all children under 2 years of age, in four doses at 2 months, 4 months, 6 months and 12 to 15 months after birth. It also recommends Prevnar for all children between ages 2 and 5 who have diseases that affect the immune system, such as sickle cell anemia and heart disease, or who have cochlear implants.
And, the CDC advises that Prevnar be considered for all children under the age of 5 who have a history of ear infections, who attend group day care, or who are of African-American, Alaska Native or American Indian descent. Such children have a higher risk of pneumococcal disease.
Where those children get their Prevnar doses may depend largely on the overall insurance patterns among patients seen at their pediatrician's or family practitioner's office, Davis notes.
The new study finds that, overall, 87 percent of the physicians surveyed were recommending Prevnar for children under age 2, the optimal age for completing the four-dose series. And nearly all -- 98 percent -- said they would administer the vaccine at their own practice location for children who had some form of coverage, whether public or private. The survey was conducted in 2001, before widespread Prevnar shortages that ended in May 2003.
But only 56 percent of physicians who recommended Prevnar reported that 100 percent of the children seen at their practice had coverage for it. Twenty percent said that 85 percent or less of their young patients had some sort of coverage.
This 85-percent-covered level turned out to be a threshold of sorts, says Davis -- only 44 percent of doctors in these practices said they would give the vaccine themselves. Physicians in states that didn't supplement VFC with vaccines for underinsured children were also significantly less likely to administer the vaccine in their own offices.
"Most of these doctors tended to recommend that children go to a different location for their Prevnar shots," Davis explains. "We know from experience and past research that this fragmentation of care leads to kids' not necessarily getting their vaccines, which is a major reason that VFC was begun. Even though the vaccine would be covered and almost free at most public locations, it becomes an additional barrier to parents, who have to take time off of work or travel a distance for a public clinic."
"Usually we've assumed that doctors are making decisions about administering a vaccine or not on a child-by-child basis," Davis explains. "But for the first time with Prevnar, we're seeing that doctors may be behaving similarly for all children in their practice based on their population. Even if they want to give it, it may be unfeasible if low numbers of children have coverage."
Interestingly, the researchers found that doctors who had treated a child who had suffered a severe illness from a pneumococcal infection -- or who had had a patient who died of such an infection -- were far more likely to say they'd administer Prevnar in their practice, regardless of the proportion of their patients who had coverage for the vaccine.
"The experience of seeing the severe illness these bacteria can cause apparently made them more willing to invest in Prevnar for their practice," says Davis. "But those who had not seen a case of serious pneumococcal disease in at least one of their patients were less likely to say they'd absorb the cost."
Those exceptions to the rule may occur in future, but Davis and his colleagues fear that vaccines now in the pipeline will lead to a replay of the worst aspects of the Prevnar situation.
"In light of the vaccines that are coming down the pike, Prevnar is an instructive lesson for all who make, market, regulate and administer vaccines," he says. "It's still not clear to what extent practices, parents and insurers will invest in increasingly expensive vaccines."
In addition to Davis and Freed, the study's authors include Serigne M. Ndiaye, Ph.D., of the CDC's National Immunization Program; and Christopher Kim, M.D., MBA and Sarah J. Clark, MPH, of the U-M CHEAR Unit, part of the Division of General Pediatrics in the U-M Department of Pediatrics and Communicable Diseases. Davis and Kim also hold academic positions in the Division of General Medicine of the U-M Department of Internal Medicine.
The study was funded by the CDC through a cooperative agreement with the Association of Teachers of Preventive Medicine.
Reference: Pediatrics, September 2003, vol. 112, number 3, www.pediatrics.org