From the Guidelines
The BCG vaccine is not given in the USA due to its unproven efficacy in the US population, its potential to confound tuberculin skin test results, and the success of other measures in reducing TB incidence. The US has a relatively low incidence of TB compared to other countries, making universal vaccination unnecessary from a public health perspective [ 1 ]. Additionally, the BCG vaccine has variable effectiveness in preventing pulmonary TB in adults, which is the most common form in the US.
The CDC recommends BCG vaccination only for select individuals, such as healthcare workers or children who are continuously exposed to untreated TB or drug-resistant TB cases, and only after consultation with TB experts [ 1 ]. The vaccine can cause a positive reaction on the tuberculin skin test (PPD), which is commonly used for TB screening in the US, making it difficult to distinguish between those who have been vaccinated and those who have been infected with TB [ 1 ]. Instead of mass vaccination, the US employs a targeted TB control strategy that focuses on identifying and treating active cases and latent infections in high-risk individuals.
Some of the key reasons for not recommending BCG vaccination for the general population include:
- Low risk of TB infection in the general population [ 1 ]
- Variable effectiveness of the vaccine in preventing pulmonary TB in adults [ 1 ]
- Potential for the vaccine to cause positive reactions on tuberculin skin tests [ 1 ]
- Success of other measures in reducing TB incidence, such as early detection, diagnosis, and treatment of TB cases, and identification and treatment of latent TB infections [ 1 ].
From the Research
BCG Vaccine in the USA
- The BCG vaccine is not widely used in the USA, and this is due to several factors, including the low incidence of tuberculosis (TB) in the country 2.
- The USA is one of the few countries that did not adopt the WHO recommendation for routine use of BCG, and this decision has been in place for many years 2.
- The lack of BCG vaccination in the USA may be attributed to the low risk of TB exposure in the general population, making the vaccine less necessary 3.
Comparison with Other Countries
- Many countries with high TB burden have implemented universal BCG vaccination, while some countries with low TB burden have discontinued mass vaccination and opted for targeted vaccination of high-risk groups 3, 4.
- The BCG World Atlas, a database of BCG practices across 194 countries, shows that 156 countries maintain universal neonatal BCG vaccination, while 51 low TB burden countries have moved to targeted vaccination for high-risk groups 4.
Implications of Not Using BCG Vaccine
- The decision not to use BCG vaccine in the USA may have implications for public health, including increased risk of TB and other diseases such as non-tuberculous mycobacteria (NTM) infections, autoimmune diseases, and neurodegenerative diseases 2.
- Some studies suggest that BCG vaccine may have immuno-modulating effects and could be used to prevent or treat various diseases, highlighting the potential benefits of reconsidering its use in the USA 2.