1921 AD
Introduction of the BCG tuberculosis vaccine
Epidemics & public health · Tuberculosis · Vacunación
BCG was first administered to humans in 1921. It became an early preventive tool against tuberculosis and was later incorporated into immunization programmes; its effectiveness depends on the form of tuberculosis, age, and epidemiological setting, so it did not eliminate the disease by itself.
Precision, calendar, and review
- Start
- year · no uncertainty qualifier in this record
- Calendar and convention
- Historical-era years; the source calendar is not identified. No conversion of days is assumed.
- Year zero
- The scale goes from 1 BCE to 1 CE without year zero. Changing era names changes labels only.
- Documentary review
- Date not recorded
Reading the date: point event.
Sources
- iris.who.int (opens in a new tab)
Source provenance and scope
- Publication date
- Pending verification: the source could not be accessed
- Bibliographic date checked
- 2026-09-23
The correspondence between this reference and individual claims has not yet been itemized.
This record is an editorial synthesis. Consult the sources to check claims and their limits. Chronological relationships alone do not establish causation.