BCG Vaccine
Note: this article is based on the Finnish vaccination policy.
Essentials
- The BCG (Bacillus Calmette-Guérin) vaccine provides good protection against the serious forms of childhood tuberculosis BCG Vaccine in the Prevention of Tuberculosis, meningeal and miliary tuberculosis. Its effect against other types of tuberculosis is markedly weaker.
- Vaccination policy varies between countries. Find out about local policy.
- In Finland, the BCG vaccine is recommended to children who are under 7 years of age and considered to be at an increased risk to be exposed to tuberculosis.
- Small infants are the most likely to develop severe disease after contracting tuberculosis, and therefore in Finland the aim is to administer the vaccine, if considered necessary, as soon as possible after birth. Children aged over seven years are not vaccinated in Finland.
Vaccination
- During pregnancy, the antenatal clinic staff assesses whether the child will need BCG vaccination.
- The vaccine is administered to neonates at the maternity hospital or - if the child falls within the immunodeficiency screening of a neonate - at the latest by the age of a few weeks elsewhere in specialized care (paediatric clinic) if the screening does not reveal a reason not to give the vaccine.
- Should a child need BCG vaccination at a later age, the vaccine may be given in specialist health care when referred by a child health clinic doctor.
- An infant aged less than six months can be vaccinated without a prior tuberculin skin test, if the child is not known to have been exposed to tuberculosis. Otherwise, if the child is over six months of age, a tuberculin skin test or an IGRA test is carried out before vaccination in order to be sure that the child has not yet contracted tuberculosis.
- BCG vaccination is recommended for a child less than 7 years of age
- whose mother, father, sibling or a person with whom the child lives has at one time been diagnosed with tuberculosis
- who himself/herself or whose mother, father, sibling or a person with whom the child lives was born in a country with a marked incidence of tuberculosis
- who has arrived from a refugee camp or, possibly, as a smuggled asylum-seeker, or who lives in an immigration reception centre or such centre for minors, and who earlier has not received BCG vaccine
- who will, within the following 12 months, spend more than one month in a country with a marked incidence of tuberculosis
- who was born in Finland and whose parent was born in Estonia (either or both parents), whose parents regularly visit Estonia or who is planned to move to Estonia.
- BCG vaccination should also be offered to a child who has other regular and close contact with a person who
- originates from a country with a high incidence of tuberculosis
- has contracted tuberculosis
- has a history of significant exposure to tuberculosis
- cares for patients with tuberculosis or is otherwise regularly and significantly exposed to tuberculosis in his/her work.
Normal vaccination reaction
- The BCG vaccine is prepared from live bacteria. An induration will develop after 2-6 weeks at the vaccination site in the left upper arm. The induration will ulcerate and then ooze for a few weeks. The reaction results in a scar which will signify successful vaccination.
- The discharging vaccination site should be covered with a dry dressing or a clean shirt. The vaccination reaction is often accompanied by a slight enlargement of regional lymph nodes.
- The discharging lesion and the resulting scar do not always develop. However, there is no need for repeat vaccinations.
Atypical vaccination reactions
- Prolonged discharge at the vaccination site
- Usually does not require treatment, not even if the discharge recurs after it has subsided. Treating BCG-Induced Disease in Children
- Large reactions, over 4 cm in diameter, are referred to specialized care.
- If the ulcer becomes tender or the redness spreads wider, this type of secondary infection can be treated with a first-generation cephalosporin. This is very seldom needed.
- An enlargement of regional lymph nodes, usually left axillary nodes following upper arm vaccination, is part of the normal vaccination reaction and investigations or treatment are not needed. Lymph nodes often remain palpable for several years.
- About 1/500-1 000 vaccinees develop lymphadenitis, which may develop into an abscess. Lymphadenitis may also develop in the supraclavicular fossa or neck. After several weeks to months the enlarged lymph node becomes fluctuating, the overlying skin turns initially red then bluish, and the abscess starts to suppurate.
- The suppuration may last for several weeks, even months, but usually is self-limiting. Further investigations or specific treatment are not required if the suppurating lymph node is not tender, there is no reddening around it and the child is otherwise well.
- After a sinus has developed, the abscess can be emptied daily by squeezing it lightly. The crater will heal with time, starting from the bottom. The abscess site can be washed normally, no extra showering or topical treatment is needed. If the abscess continues to suppurate, the child should not swim in public swimming pools.
- A disseminated infection is an adverse event of BCG vaccination and occurs in about 1/7 000 vaccinees. The most common disseminated infection is osteitis.
- A rare, severe adverse event occurring usually only about one year after BCG vaccination
- Symptoms include pain, tenderness and swelling at the site of osteitis.
- The treatment requires specialist intervention.
- BCG vaccination may cause a life threatening systemic infection in a severely immunocompromised child.
- A communicable disease notification must be submitted on all abnormal vaccination reactions (national regulations and guidelines apply).
References