Increasing COVID-19 Vaccination Rates Amongst Children with Sickle Cell Disease: A Quality Improvement Project

Background: Individuals with sickle cell disease (SCD) are at an increased risk of complications from COVID-19. The COVID-19 vaccine safely protects children with SCD against serious COVID-19 disease.

Objective: To increase the proportion of children with SCD receiving >2 doses of the COVID-19 vaccine to >70% by July 1st 2022.

Methods: This quality improvement (QI) project was conducted at an academic pediatric hospital. The project team consisted of physicians, nurses, and advanced practice practitioners. We used the Model for Improvement as the improvement framework.

We identified patients with SCD eligible for vaccine via our institution's data warehouse. Patients who received their primary hematology care at an alternative institution and those under 5 years of age were excluded. Baseline data was collected for five months prior to and then bi-weekly during the intervention period. Our SMART aim was to increase the proportion of eligible patients receiving the COVID-19 vaccine to >70% by July 1st 2022. We identified primary and secondary drivers of under-vaccination and then formulated change strategies. Three plan-do-study-act (PDSA) cycles were performed: 1) Information encouraging vaccination was sent to the families of children who were under-vaccinated via text message. Providers received a monthly report of their patients' vaccination statuses; 2) An automated weekly report of expected clinic patients' vaccination status was sent to the clinic team. Under-vaccinated patients were contacted prior to their appointment and offered a vaccination; 3) We sent patients and parents a video highlighting vaccine importance with a pediatric hematologist, a patient's mother, and a nurse via text message and posted a QR code linking to the video in our clinic (https://youtu.be/MY7C2Kt2tuI).

The outcome measure was the proportion of patients who received >2 doses of the COVID-19 vaccine. The process measure was the number of patients who booked a vaccination. The balancing measure was the proportion of missed appointments. Statistical process control charts were used to track changes over time.

Results: 243 patients were eligible for the COVID-19 vaccine. Changes in the vaccination rate during the pre-intervention (Sept 2021-January 2022) and intervention (February 2022-June 2022) periods are shown in Figure 1. COVID-19 vaccination rate increased from a baseline of 34% to 64% by June 2022. Based on the trend in vaccine uptake pre-intervention, the expected vaccination rate without any intervention was 51% in June 2022. There was no increase in missed clinic visits (9.0% of visits prior to the study vs. 9.6% during the study). When patients were contacted to schedule a vaccine appointment 10 (13.5%) booked a vaccine, 6 (8.1%) had received a vaccine that was not captured in our system, 19 (25.7%) articulated a barrier or concern to vaccination, 11 (14.8%) refused the vaccine, and 28 (37.8%) could not be reached.

Conclusion: Via a QI initiative, we increased the vaccination rate for eligible patients with SCD without an increase in missed clinic visits. While our final vaccination rate of 64% did not reach our target of 70%, we did achieve a rate that exceeds the national average (44%), and a rate that is comparable to the highest level of vaccination in children nationwide (70%). Our final vaccination rate also exceeds the predicted vaccination rate our cohort based on the pre-intervention cadence of vaccination. We found that targeting misinformation regarding safety, mitigating logistical barriers, and increasing provider awareness of patients' vaccine status were effective ways to increase COVID-19 vaccination rates. Future work will focus on engaging with local community partners to offer individuals with SCD the COVID-19 vaccine at community-based events and on addressing the barriers and concerns articulated by patients.

Archer:Global Blood Therapeutics: Research Funding; Novartis: Research Funding; Haemonetics: Other: Stocks are provided to my husband as part of his compensation as an employee of the company. Heeney:Bluebird Bio: Consultancy; Vertex/ Crisper Therapeutics: Consultancy; Oric Pharmaceuticals: Consultancy; FORMA Therapeutics: Consultancy; Novartis: Consultancy.