Does intravesical Bacillus Calmette-Guérin for bladder cancer protect from COVID-19?

Area of Science:

• Urology
• Infectious Diseases
• Immunology

Background:

• The Bacillus Calmette-Guérin (BCG) vaccine is used for both tuberculosis prevention and intravesical treatment for bladder cancer.
• The potential impact of BCG on other infections, including COVID-19, has been a subject of interest due to its known immunomodulatory effects.

Purpose of the Study:

• To investigate the correlation between a history of intravesical BCG instillations and infantile BCG immunization and the incidence and severity of COVID-19 infection.
• To determine if BCG exposure influences susceptibility or clinical outcomes of SARS-CoV-2 infection in patients with non-muscle invasive bladder cancer (NMIBC).

Main Methods:

• A retrospective data collection was performed on patients diagnosed with high-risk NMIBC at two Canadian centers.
• Data included patient demographics, history of intravesical BCG therapy, infantile BCG vaccination status, and COVID-19 infection status, including hospital admission and mortality.

Main Results:

• The study included 348 patients (188 from Ontario, 160 from British Columbia).
• COVID-19 affected 15% of the patient cohort.
• No statistically significant correlation was found between a history of intravesical BCG or infantile BCG immunization and the incidence or severity of COVID-19 infection.

Conclusions:

• A history of intravesical BCG treatment or infantile BCG vaccination did not alter the likelihood of contracting COVID-19.
• BCG exposure, either through bladder cancer treatment or childhood immunization, was not found to be a significant factor in the COVID-19 outcomes for this NMIBC patient group.