Vaccine to Prevent Tuberculosis (TB):BCG Vaccine


BCG or Bacille Calmette-Guerin is a vaccine for tuberculosis (TB) disease. the BCG vaccine should be considered only for very select persons who meet specific criteria and in consultation with a TB expert.

December 14, 2017

BCG or Bacille Calmette-Guerin is a vaccine for tuberculosis (TB) disease. BCG is used in many countries with a high prevalence of TB to prevent childhood tuberculous meningitis and miliary disease. However, the BCG vaccine should be considered only for very select persons who meet specific criteria and in consultation with a TB expert.

BCG vaccine is recommended for:

Children:

BCG vaccination

should only be considered for children who have a negative tuberculin skin test and who are continually exposed. Also this can be considered if the child cannot be given long-term treatment for infection and cannot be separated from, adults who

  •     Are untreated or ineffectively treated for TB disease
  •     Have TB caused by strains resistant to isoniazid and rifampin

Health Care Workers:

BCG vaccination of health care workers should be considered on an individual basis in settings in which

  • A high percentage of TB patients are infected with M. tuberculosis strains resistant to both isoniazid and rifampin
  • There is ongoing transmission of such drug-resistant M. tuberculosis strains to health care workers and subsequent infection is likely
  • Comprehensive TB infection-control precautions have been implemented, but have not been successful.

Regarding the risks and benefits associated with both BCG vaccination and treatment of Latent TB Infection (LTBI), the health care workers considered for BCG vaccination should be counseled.

Who should not get this vaccine:

  • BCG vaccination should not be given to persons who are immuno-suppressed such as, persons who are HIV infected or who are likely to become immuno-compromised. A persons who are candidates for organ transplant is most likely to become immuno-compromised.
  • BCG vaccination should not be given during pregnancy. Even though no harmful effects of BCG vaccination on the fetus have been observed, as a preventive it is not recommended in pregnancy.

Testing for TB in BCG-Vaccinated Persons:

For persons who have been vaccinated with BCG, both the test either it is tuberculin skin test (TST) and blood tests is not contraindicated.

Tuberculin Skin Test (TST):

BCG vaccination may cause a false-positive reaction to the TST. The presence or size of a TST reaction in persons who have been vaccinated with BCG does not predict whether BCG will provide any protection against TB disease and also the size of a TST reaction is not a factor in determining whether the reaction is caused by LTBI or the prior BCG vaccination.

TB Blood Tests:

These are less likely to give a false-positive result as these tests are not affected by prior BCG vaccination.

Treatment for LTBI in BCG-Vaccinated Persons:

The risk that TB infection will progress to disease can be reduced by treatment of LTBI. The same criteria should be used to interpret the evaluation of TST reactions in persons vaccinated with BCG as those for not BCG-vaccinated.
If a persons in the following high-risk groups has a reaction to the TST is at least 5 mm of induration or they have a positive result using a TB blood test, should be given treatment for LTBI. The high risk groups are:

  • HIV-infected persons
  • Recent contacts to a TB case
  • Persons with fibrotic changes on chest radiograph consistent with old TB
  • Patients with organ transplants
  • Persons who are immunosuppressed for other reasons such as taking high dose of prednisone for longer or taking TNF-a antagonists

When a persons in the following high-risk groups has a reaction to the TST is at least 10 mm of induration or they have a positive result using a TB blood test, should be given treatment for LTBI. The high risk groups are:

  • Recent arrivals that could be less than 5 years, from high-prevalence countries
  • Injection drug users
  • Residents and employees of high-risk congregate settings such as, correctional facilities, nursing homes, homeless shelters, hospitals, and other health care facilities
  • Mycobacteriology laboratory personnel
  • Persons with clinical conditions that place them at high-risk for developing TB disease such as, diabetes
  • Children less than 4 years of age, or children and adolescents exposed to adults in high-risk categories

If the reaction of a person to the tuberculin test is at least 15 mm of induration or they have a positive result using a TB blood test, may be considered for treatment of LTB even if there is no known risk factors for TB.

Problems that could happen after any vaccine:

  • Sometimes people faint after vaccination. Sitting or lying down for about 15 minutes can help prevent fainting. If you feel dizzy, have vision changes or ringing in the ears, speak to your doctor.
  • In some cases severe pain in the shoulder and difficulty moving the arm where a shot was given could happen.
  • A severe allergic reaction would happen within a few minutes to a few hours after the vaccination.
  • There is a very remote chance of a vaccine causing a serious injury or death. The safety of vaccines is always being monitored. You can get all the information from Vaccine Safety site.

Signs of a severe allergic reaction can include hives, swelling of the face and throat, difficulty breathing, a fast heartbeat, dizziness, and weakness. These would start a few minutes to a few hours after the vaccination. If you have severe allergic reaction, very high fever, or behavior changes , call 9-1-1 or find the nearest hospital.
The reaction should be reported to the Vaccine Adverse Event Reporting System (VAERS) through the VAERS website or by calling 1-800-822-7967. VAERS is only for reporting reactions. They do not give medical advice.
If you are injured by a vaccine, you can file a claim in  National Vaccine Injury Compensation Program (VICP) by calling 1-800-338-2382 or visiting the VICP website to get the compensation.

Learn more about Vaccine:

Your doctor can give you the vaccine package insert or suggest other sources of information.
You can call your local or state health department or can contact the Centers for Disease Control and Prevention (CDC) by:
        Calling 1-800-232-4636 (1-800-CDC-INFO)
        Visiting  CDC vaccines website