Findings indicate computerized systems and public/private sector collaboration more widely needed

(Feb. 2, 2009) – Influenza alone causes more than 20,000 hospitalizations and 260 deaths in children in the United States annually. During the 2004-2005 flu season, a severe vaccine shortage occurred across the United States because all of the flu vaccine produced by a major manufacturer was deemed unusable. Immediately following the flu season that year, researchers affiliated with the Rocky Mountain Prevention Research Center at the University of Colorado Denver undertook a nationwide survey of pediatricians to determine the extent of the shortage, the impact on patient care and the problems that were caused by shortages or delays in delivery. The survey was administered from March through June 2005 and was funded by the Centers for Disease Control (CDC). The results appear in the February 2009 edition of Pediatrics.

The authors’ results of the survey reveal the fragility of the US influenza vaccine supply, particularly for children, and highlight areas in which more work is needed, including the efficiency of vaccine redistribution and methods to better prioritize and identify children at high risk. Prior to this survey, very little was known about the effects of vaccine shortages on individual providers and how providers might deal or cope with problems caused by shortages.

“Influenza is the perfect storm for pediatricians—approximately one year before the next flu season they have to estimate how much vaccine they are going to need. If they order too much they can’t keep it for use the following year or return it, so ordering is a financial gamble each year,” said Allison Kempe, MD, MPH, professor of pediatric medicine at the University of Colorado Denver School of Medicine, pediatrician at the Children’s Hospital in Aurora, Colo., and coauthor on the study. “The severe influenza vaccine shortage experienced during the 2004-2005 flu season offered an opportunity to study the impact of vaccine shortages.”

The vaccine also is delivered in a fairly narrow window—approximately four months—and children receiving the shot for the first time require two doses, so pediatricians often hold clinics to get larger numbers of children vaccinated efficiently. The difficulty of scheduling these clinics is compounded by the fact that, even in years when there is not a vaccine shortage, delays in delivery of the vaccine occur, some shipments are staggered and unpredictability of delivery is encountered almost every season. “On top of all of this, national recommendations regarding which children should be vaccinated have been greatly expanded in recent years, so that the number of children pediatricians need to vaccinate has ballooned,” added Kempe.

The 2004-2005 shortage occurred after Chiron, a manufacturer of the vaccine, announced in October 2004 that none of its vaccine would be available for US distribution, affecting approximately half of the US supply. The authors hypothesized that those pediatricians who were dependent on the Chiron vaccine as their only source of vaccine distribution would be the hardest hit but the survey results found this was not necessarily the case. From a survey response rate of 82 percent (352 of 427), only a small percentage (14 percent) reported ordering the Chiron vaccine, but almost half reported shortages for patients at high risk.

“A substantial percentage of pediatricians were affected by the vaccine shortage despite the fact that very few ordered the Chiron vaccine,” said Kempe. “The majority of pediatricians may not have been able to efficiently identify and recall children at high risk due to a lack of computerized systems in place and while we found that a great deal of vaccine redistribution occurred between the public and private sectors, data suggests there were inefficiencies.”

During the shortage, the CDC encouraged cooperation between public health departments and private practices to redistribute available vaccine to providers with greater shortages. The survey findings indicate there was extensive redistribution of vaccine during the shortage—48 percent reported receiving additional vaccine from an outside source after the shortage was announced and the most frequent source of additional vaccine was from a public health entity.

Despite the CDC’s efforts, 49 percent of pediatricians responding to the survey indicated they had unused vaccine left at the end of the flu season, and 14 percent had 10 percent or more of their total supply leftover. “The amounts that were left at the end of the season could have been redistributed to those in need earlier on,” said Kempe.

Since the time the survey was conducted, the CDC has expanded its pediatric recommendation to include routine vaccination of children aged 24 months to 18 years (previously it was only recommended for children ages 6 months to 23 months and high-risk children older than 2 years). Presently, there are an increased number of vaccine manufacturers that may increase supply but it is unclear how the expanded recommendations for routine flu vaccination will affect supply and distribution issues relevant to future shortages.

“Ideally in a year of severe vaccine shortage, redistribution efforts should be coordinated and organized more systematically between the private and public sectors to ensure prioritization to reach high-risk patients,” said Kempe. “The majority of pediatricians in our study did not have a computerized system to aid them in identifying, prioritizing and recalling patients who needing the vaccine and these systems would be beneficial, particularly when limited supplies are available.”

“Given the expanded recommendations to vaccinate all children, providers are unlikely to be able to handle the volume alone and the approach really needs to be more of a community effort,” added Kempe. “The solution lies in a creative and collaborative approach to ensure that those at highest risk are given priority for the vaccine in a shortage.”

Kempe indicated collaborations to efficiently vaccinate all children would be most beneficial between public health entities, local school districts and private providers. Currently, Denver Health Medical Center, the Colorado Department of Public Health and Environment and Denver Public Schools are considering participating in a study to test the effectiveness of collaboration in flu vaccine distribution to area children.

The University of Colorado Denver School of Medicine faculty work to advance science and improve care as the physicians, educators and scientists at University of Colorado Hospital, The Children’s Hospital, Denver Health, National Jewish Health, and the Denver Veterans Affairs Medical Center. Degrees offered by the CU Denver School of Medicine include doctor of medicine, doctor of physical therapy, and masters of physician assistant studies. The School is part of the University of Colorado Denver, one of three campuses in the University of Colorado system. For additional news and information, please visit the CU Denver newsroom online.

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