The BCG vaccine may protect against long COVID symptoms

TOPLINE:

Administration of the Bacillus Calmette-Guérin (BCG) vaccine during the active phase of COVID-19 may help protect against the development of long COVID.

METHODOLOGY:

• A Phase 3 clinical trial begun in early 2020 examined the effect of BCG vaccine injected during active infection on the progression of COVID-19 in adults with mild or moderate COVID-19. The current study summarizes the 6- and 12-month follow-up data with a focus on long-COVID symptoms.
• Patients who tested positive for severe acute respiratory syndrome coronavirus 2 were randomly assigned to receive either 0.1 mL intradermal BCG (n=191) or 0.9% saline placebo (n=14 days) within 14 days of symptom onset = 202) and were examined after 7 days. 14, 21 and 45 days and 6 and 12 months after injection.
• A total of 157 BCG recipients (mean age, 40 years; 54.1% women) and 142 placebo recipients (mean age, 41 years; 65.5% women) completed the 6-month follow-up, and 97 BCG recipients (mean age, 37 years; 49.5%). % women) and 95 placebo recipients (mean age 40 years; 67.4% women) completed the study at 12-month follow-up.
• The researchers primarily examined the effect of the BCG vaccine on the development of symptoms of long COVID at 6 and 12 months.

TAKE AWAY:

• Hearing problems were less common in BCG recipients at 6 months than in those receiving placebo (odds ratio (OR) 0.26; 95% CI 0.045–1.0; P = .044).
• After 12 months, participants who received the BCG vaccine showed fewer problems with sleeping (P = .027), concentration (P = .009), memory (P = .009) and eyesight (P = .022) along with a lower Long COVID score (one-tailed Wilcoxon test, P = .002) than those who received a placebo.
• After 6 months, BCG showed a sex-specific paradoxical effect on hair loss, reducing it in men (P = .031), while there was a slight, although not statistically significant, increase for women.
• At both follow-ups, male gender was the strongest predictor of long COVID, cognitive dysfunction, and cardiopulmonary scores.

IN PRACTICE:

“The results of the study suggest that BCG immunotherapy in the setting of existing disease may be superior to prophylaxis in healthy individuals,” the authors write.

SOURCE:

The study was led by Mehrsa Jalalizadeh and Keini Buosi, UroScience, State University of Campinas, Unicamp, São Paulo, Brazil. It was published online on November 19, 2024 Magazine for Internal Medicine.

RESTRICTIONS:

Previous exposure to mycobacteria was not tested in the study participants. Significant loss to follow-up, particularly at 12 months, may have biased the results.

DISCLOSURES:

The study was supported by the Coordination for the Improvement of Higher Education Human Resources of the Federal Government of Brazil, the General Coordination of the National Immunization Program, the Ministry of Health (Brazil), and the National Council for Scientific and Technological Development and Research Productivity. The authors declared that there were no conflicts of interest.

This article was created as part of this process using multiple editorial tools, including AI. Human editors reviewed this content before publication.