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Is a 6 week Waiting Period Necessary? Challenging Historic Dogma on Timing of BCG Treatment and Vaccine Administration
Philip Olson, MD1, Jonathan Saidon, BS
2, Ilene Staff, PhD
2, Kevin Pinto, BS
2, Tara McLaughlin, PhD
2, Laura Olivo Valentin, BS
2, Joseph Tortora, MS
2, Ulysses Wu, MD
2, Anoop Meraney, MD
2.
1UConn Health, Farmington, CT, USA,
2Hartford Healthcare, Hartford, CT, USA.
BACKGROUND: Theoretical dogma warns against an increased rate of adverse events when intravesical Bacillus Calmette-Guerin (BCG) overlaps with administration of the influenza vaccine. The British Association of Urologic Surgeons and NHS-associated hospitals recommend waiting 6 weeks between administration of each, despite no supporting data. However, this practice can lead to unnecessary delays in treatment and in life-saving vaccination. In response, we identified patients who received BCG and the COVID-19 and/or influenza vaccination and examined the rates of adverse events for different waiting periods between vaccine and BCG administration.
METHODS: After IRB approval, we identified patients who received either induction or maintenance BCG between September 6, 2023- April 10, 2024. We determined time and date of vaccine administration. Timing of vaccine in reference to intravesical BCG was categorized as >6 weeks, >2 weeks and ≤6 weeks, and ≤2 weeks. Patients in each vaccine window were compared for rates of urinary and non-urinary adverse events using Chi-square.
RESULTS: 231 patients who received intravesical BCG were included; 134 received the COVID vaccine, flu vaccine or both. 56 (42%) received either vaccine >6 weeks from BCG, 38 (28%) between >2 weeks and ≤6 weeks, and 40 (30%) at ≤2 weeks (Table 1). 97 (42%) did not obtain either vaccine during the study period. No group differences were noted in rates of urinary or non-urinary adverse events or in rates of any individual adverse event (Table 1).
CONCLUSIONS: We found no association between adverse events and timing of COVID and/or influenza vaccine relative to intravesical BCG administration. These results support the safety of a 2-week waiting period, therefore the administration of necessary vaccines or intravesical BCG should not be delayed.
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