Live Immunization Practices for Chronically Transfused Pediatric Patients
Bibliographic record
Abstract
Abstract Introduction: Children with hemoglobinopathies often require chronic transfusion as a part of their care. The Canadian Immunization Guide, the National Advisory Committee on Immunizations, and the Centre for Disease Control recommend avoidance of live vaccination for a period following blood product transfusion. The literature indicates that human derived blood products contain significant amounts of antibodies to infectious agents that are prevalent in the general population, due to natural disease or vaccination of the donor, such as the measles virus and varicella zoster virus. The recommended time interval between packed red blood cell (PRBC) transfusion and live vaccination was extrapolated from a study which assessed vaccine responses after administration of Intravenous immune globulin. If practitioners adhere to guidelines, many chronically transfused pediatric patients would not be eligible to receive live vaccinations due to concerns of non-response to the vaccine. Thecomposition of blood products has changed over time and current immunization recommendations may not reflect the blood products being utilized today. Specifically, the amount of residual plasma in PRBCs has been reduced substantially, reducing passive antibody concentration and likely reducing interference in the immune response. To our knowledge, the immune response to live vaccines has not been formally studied in pediatric patients who undergo chronic transfusion with PRBCs. We aimed to determine the current live immunization practices of health care providers (HCPs) caring for chronically transfused pediatric patients. Hypothesis: Is there heterogeneity in the live immunization practices of North American Pediatric HCPs who care for chronically transfused children? Methods: The study was approved by the University of Alberta Research Ethics Board. A cross-sectional online survey was circulated to North American hematology HCPs. The survey was peer-reviewed by 7 practitioners prior to distribution for content and face validity with 3 versions before final approval and distribution. The survey was distributed via the Canadian Hemoglobinopathy Association (CanHaem,186 members) and the American Society of Pediatric Hematology/ Oncology (ASPHO, 1991 members) listservs. Responses were collated from June 2017-July 2017 in a REDcap database. Data was analyzed using descriptive statistics. Results: There were 60 respondents total. 60% of HCPs were from the U.S.A., and 70% cared for 1-19 patients meeting study criteria. The majority had 1-10 patients who travelled to measles endemic countries annually, and 33% of HCPs reported there had been a local outbreak of Measles, Mumps, Rubella or Varicella (MMRV) within the past year. Despite this, 50% were unaware of the MMRV immune-status of their patients. Eighty-seven percent of HCPs continued to administer live vaccinations as per the routine immunization schedule. Less than 10% had a protocol for the care of chronically transfused patients, and Conclusion: Live immunization practices for chronically transfused pediatric patients vary across North America. Many HCPs are unaware of the recommendations around avoidance of live immunizations post transfusion. Most respondents immunize their chronically transfused pediatric patients as per the routine schedule, but the immune-status post-vaccination is often unknown. Given changes to the processing of blood products over the last several decades, further research is needed in this area. Determination of pre-and-post-immunization serologies may help to establish the response of chronically transfused patients to live vaccinations, and allow for the development of evidence-based guidelines for live-immunization of this vulnerable patient population. Disclosures Bruce: Bristol-Meyers-Squibb - consultant 2016-2017: Consultancy; ovartis consult and ad board 2015-2016: Consultancy; Apopharma 2015: Consultancy.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.000 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one teacher head, not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".