Related Experiment Video
Updated: Nov 10, 2025

Protective Efficacy and Pulmonary Immune Response Following Subcutaneous and Intranasal BCG Administration in Mice
Published on: September 19, 2016
The safety of BCG revaccination: A systematic review
Samantha Bannister1, Eva Sudbury1, Paola Villanueva1
1Department of Paediatrics, The University of Melbourne, Parkville, Victoria, Australia; Infectious Diseases Research Group, Murdoch Children's Research Institute, Parkville, Victoria, Australia; Infectious Diseases Unit, Royal Children's Hospital Melbourne, Parkville, Victoria, Australia.
Introduction:
Revaccination with Bacillus Calmette-Guérin (BCG) vaccine is not generally recommended due to a lack of proven efficacy of repeat doses for protection against tuberculosis. However, there is a growing interest in the use of BCG vaccine for its 'off-target' effects which might involve revaccination. We did a systematic review of the safety of BCG revaccination.
Methods:
MEDLINE (1946 to March 2020) and the BCG World Atlas (updated 2017) were searched, limiting to studies of BCG administration by the intradermal or percutaneous route. Adverse events as well as patient and vaccine characteristics were reviewed.
Results:
The search identified 388 articles, of which 24 met the inclusion criteria. These reported 22 studies comprising eight randomised trials, four case-control studies, four observational studies and six case series or reports. Overall, there was evidence for a small increase in the rate of mild local and systemic reactions. No serious adverse events were reported in immunocompetent individuals.
Conclusions:
Evidence to date suggests that revaccination with BCG vaccine carries minimal risk. Future studies of BCG vaccine for novel applications should report adverse event data stratified by prior BCG vaccination status.
Related Concept Videos
Vaccinations
Cancer Vaccines
Cancer vaccines come in two categories: preventive (prophylactic) and treatment (active). Preventive vaccines, such as the Human Papillomavirus (HPV) vaccine, protect against viruses that cause certain...
Types of Biopharmaceutical Studies: Controlled and Non-Controlled Approaches
Non-controlled studies, commonly employed for initial exploration, lack a control group, rendering them susceptible to biases and external influences. In contrast,...
Cross-reactivity
Bioequivalence studies: Biowaivers
Pharmacovigilance
This process, termed pharmacovigilance, aims to detect, evaluate, and minimize harmful effects related to medication use. The data collection for pharmacovigilance depends on spontaneous reporting systems, where healthcare professionals or patients voluntarily report suspected ADRs.
In some cases, there...

