<<–2/”>a href=”https://exam.pscnotes.com/5653-2/”>h2>BCG: A Comprehensive Overview
What is BCG?
BCG stands for Bacillus Calmette-Guérin. It is a vaccine primarily used to protect against tuberculosis (TB), a serious infectious disease that mainly affects the lungs. BCG is a live, weakened form of the bacteria Mycobacterium bovis, which is closely related to the bacteria that causes TB in humans (Mycobacterium tuberculosis).
How BCG Works
BCG works by stimulating the immune system to develop a defense against TB. When the vaccine is injected, the weakened bacteria multiply in the body, triggering an immune response. This response creates memory cells that can recognize and fight off M. tuberculosis if the individual is exposed to the bacteria in the future.
Effectiveness of BCG
The effectiveness of BCG in preventing TB varies depending on several factors, including:
- Age at vaccination: BCG is most effective when given to infants.
- Strain of BCG: Different strains of BCG have varying levels of effectiveness.
- Prevalence of TB in the Population: BCG is more effective in areas with high TB prevalence.
Table 1: Effectiveness of BCG in Different Settings
| Setting | Effectiveness |
|---|---|
| Infants in high TB prevalence areas | 80% reduction in risk of TB |
| Infants in low TB prevalence areas | 50% reduction in risk of TB |
| Adults in high TB prevalence areas | 20-30% reduction in risk of TB |
| Adults in low TB prevalence areas | Minimal protection |
Administration of BCG
BCG is typically given as a single injection into the upper arm. The vaccine is usually administered to infants, but it can also be given to older children and adults in some cases.
Side Effects of BCG
BCG is generally safe, but it can cause some side effects, including:
- Local reactions: Redness, swelling, and pain at the injection site.
- Regional lymph node enlargement: Swollen lymph nodes in the armpit or neck.
- Other rare side effects: Fever, malaise, and skin rashes.
Table 2: Common Side Effects of BCG
| Side Effect | Frequency |
|---|---|
| Redness, swelling, and pain at the injection site | Common |
| Regional lymph node enlargement | Common |
| Fever | Uncommon |
| Malaise | Uncommon |
| Skin rashes | Rare |
Contraindications and Precautions
BCG should not be given to individuals with:
- Severe immunodeficiency: Individuals with weakened immune systems are at increased risk of serious complications from BCG.
- HIV infection: BCG is not recommended for individuals with HIV infection.
- Active TB: BCG should not be given to individuals with active TB.
BCG and Other Vaccines
BCG can be given at the same time as other vaccines, but it is important to consult with a healthcare professional to ensure that the vaccines are compatible.
BCG and TB Testing
BCG vaccination can interfere with some TB tests, such as the tuberculin skin test (TST). This is because BCG can cause a positive TST result, even if the individual does not have TB.
BCG and TB Treatment
BCG does not cure TB. If an individual develops TB after receiving BCG, they will need to be treated with antibiotics.
Frequently Asked Questions
Q: Is BCG mandatory?
A: BCG vaccination is not mandatory in most countries, but it is highly recommended for infants in areas with high TB prevalence.
Q: How long does BCG protection last?
A: BCG protection typically lasts for 10-15 years, but it can provide some protection for life.
Q: Can I get BCG if I have already had TB?
A: No, BCG should not be given to individuals who have already had TB.
Q: Can I get TB after receiving BCG?
A: Yes, it is possible to get TB after receiving BCG. However, BCG significantly reduces the risk of developing TB.
Q: Is BCG effective against all strains of TB?
A: BCG is most effective against M. tuberculosis, the strain that causes most cases of TB. However, it may not be as effective against other strains of TB.
Q: What are the long-term effects of BCG?
A: The long-term effects of BCG are generally unknown. However, there is no evidence to suggest that BCG causes any serious long-term Health problems.
Q: Is BCG available in all countries?
A: BCG is available in most countries, but it may not be available in all areas.
Q: Where can I get BCG?
A: BCG is typically administered by healthcare professionals at clinics or hospitals.
Q: How much does BCG cost?
A: The cost of BCG varies depending on the country and the healthcare provider.
Q: Is BCG safe for pregnant Women?
A: BCG is generally safe for pregnant women, but it is important to consult with a healthcare professional before receiving the vaccine.
Q: Is BCG safe for breastfeeding mothers?
A: BCG is generally safe for breastfeeding mothers. However, it is important to consult with a healthcare professional before receiving the vaccine.
Q: What should I do if I have a reaction to BCG?
A: If you have a reaction to BCG, it is important to consult with a healthcare professional. Most reactions are mild and resolve on their own, but some may require medical attention.