Impact of the 2004-2005 Influenza Vaccine Shortage on Pediatric Practice: A National Survey
ABSTRACT A severe influenza vaccine shortage occurred during the 2004-2005 influenza season because of the loss of all vaccine made by Chiron (Emeryville, CA) for US distribution.
The objectives of this study were to assess among pediatricians nationally: (1) influenza vaccine-delivery strategies; (2) reported vaccine shortages and factors associated with experiencing shortages; and (3) the impact of shortages on vaccine redistribution, patient referral, and clinical practice, including patient prioritization.
A survey was administered in March 2005 through June 2005 to 427 pediatricians who participated in a national network representative of the American Academy of Pediatrics membership. RESULTS. Our response rate was 82%. Thirty-nine percent of the pediatricians had a computerized method for identifying patients at high risk needing vaccination. Ninety-four percent and 79% reported giving high-priority to children >/=24 months old with high-risk conditions and children 6 to 23 months old, respectively, whereas 41% gave high-priority to household contacts and caregivers of children <6 months old. Forty-three percent reported experiencing shortages of vaccine for patients at high risk, whereas only 14% ordered Chiron vaccine. In multivariate analyses, ordering vaccine from Chiron and ordering Aventis Pasteur (Lyon, France) vaccine solely from a vaccine distributor were associated with experiencing a shortage. Forty-eight percent of respondents obtained additional vaccine from another source, most frequently the public health sector, whereas 37% reported selling or giving away vaccine. In addition, 47% referred patients at high risk elsewhere for vaccination, primarily to public health clinics. Forty-nine percent reported having unused vaccine remaining at the end of the season.
Although few pediatricians ordered Chiron vaccine, substantial influenza vaccine shortages were reported, highlighting the tenuousness of injectable influenza vaccine supplies for children. The extensive redistribution of vaccine suggests that cooperative efforts between the private and public sectors were widespread. Efforts to vaccinate patients at high risk during shortages would be aided by better systems to identify and recall these patients.
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ABSTRACT: Adaptive array weight adjustment algorithms are described by time varying stochastic differential equations. A new method employing a two-variable perturbation analysis is used to investigate the effects of the weight fluctuations on the Applebaum algorithm performance in the presence of multiple jammers. An explicit solution of the directivity pattern in the direction of the jammers for the two-jammer problem is derived. An improved formula for the output signal-to-interference plus noise ratio (SINR) is obtained. It is shown as expected that the greater the number of signals at the array input the greater the degradation in the directivity pattern in the direction of the interfering signals and the greater the degradation in the output SINR. In addition, we show that the performance degrades uncontrollably when the number of independent jammers approaches the number of array elements. A comparison is made of the new results and those obtained using standard approximations. Substantial differences are caused by first-order terms in the perturbation.Military Communications Conference, 1985. MILCOM 1985. IEEE; 11/1985
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ABSTRACT: SUMMARY The challenges in successful vaccination against influenza using conventional approaches lie in their variable efficacy in different age populations, the antigenic variability of the circulating virus, and the production and manufacturing limitations to ensure safe, timely, and adequate supply of vaccine. The conventional influenza vaccine platform is based on stimulating immunity against the major neutralizing antibody target, hemagglutinin (HA), by virus attenuation or inactivation. Improvements to this conventional system have focused primarily on improving production and immunogenicity. Cell culture, reverse genetics, and baculovirus expression technology allow for safe and scalable production, while adjuvants, dose variation, and alternate routes of delivery aim to improve vaccine immunogenicity. Fundamentally different approaches that are currently under development hope to signal new generations of influenza vaccines. Such approaches target nonvariable regions of antigenic proteins, with the idea of stimulating cross-protective antibodies and thus creating a "universal" influenza vaccine. While such approaches have obvious benefits, there are many hurdles yet to clear. Here, we discuss the process and challenges of the current influenza vaccine platform as well as new approaches that are being investigated based on the same antigenic target and newer technologies based on different antigenic targets.Clinical microbiology reviews 07/2013; 26(3):476-92. DOI:10.1128/CMR.00097-12 · 16.00 Impact Factor
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ABSTRACT: To assess racial/ethnic disparities in preventive care practices among U.S. nursing home residents. To implement the Institute of Medicine definition of health care disparity, we used the rank-and-replace adjustment method to assess the disparity in receipt of eight preventive care services among residents and evaluate trends in disparities. The sampling design (stratification and clustering) was accounted for using Stata 11. The 2004 National Nursing Home Surveys data show White residents were more likely to have pain management, scheduled toilet plan/bladder retraining, influenza vaccination, and pneumococcal vaccination than Black residents. White residents were also more likely to have scheduled toilet plan/bladder retraining than residents of Other race/ethnicity. Significant Black-White disparities in receipt of influenza vaccination and pneumococcal vaccination were found. Time trend analysis showed that disparities were neither exacerbated nor reduced. Persistent racial/ethnic disparities in preventive care among nursing home residents exist. We urge the development and implementation of targeted interventions to improve the quality of preventive care in nursing homes.Journal of Aging and Health 03/2014; 26(4). DOI:10.1177/0898264314524436 · 1.56 Impact Factor