The BCG vaccine for TB has been used for 100 years. It is largely effective for children under five, but less so in older people and can’t be used on patients who have certain medical conditions. Today we’re the closest we’ve ever been to discovering a vaccine that might replace or complement it. Charles Shey Wiysonge, the World Health Organization’s Regional Adviser for Immunisation, discusses the latest developments in the fight against one of the world’s deadliest diseases.
Why has it taken so long? We do not yet have a new vaccine for TB. But, for the first time, there are several vaccine candidates that are at advanced stages of clinical development. Vaccine development usually takes decades and unfolds step by step. Experimental vaccine candidates are created in the laboratory and tested in animals before moving into progressively larger human clinical trials. Clinical trials are research studies that test an intervention such as a vaccine in human beings and occur in phases, from phase 1 to phase