Monitoring of adverse events of BCG vaccination in Moscow, Russia

Abstract

Background: Wide BCG vaccination coverage (which is carried out later than 3 days after birth) in Moscow (96%, 2014) requires the organization of monitoring of adverse events of vaccination (AE) which has been realized based on computerized register since 2000. It gives opportunities to investigate the AE structure in order to determine their possible connection with vaccine quality, a violation of the rules of its transportation, storage and use.

Method: 295 adverse events including lymphadenitis (LPh), local abscess (LAb) and suppuration (SP), osteitis (OSt) and disseminated BCG (DBCG), registered in 2004-2014 were analyzed.

Results: Rate of LAb and SP was 0.01 per 100K of vaccinated children, and rates of LPh and OSt were 0.006 and 0.004 per 100K, accordingly.

62.0% (95% CI 56.2 -67.6) of AE were notified among children vaccinated in maternity hospitals, and 36.3% (30.8 -42.0) – in polyclinics.

AE structure mostly included: Lab - 46,4% (40.6 – 52.3), LPh – 33.9% (28.5- 39.6) and OSt – 19.7% (15.2 – 24.6). DBCG was registered only in 7 cases which were observed in the case of presence of immunodeficiency.

Age of children at the time of AE was from 2 to 47 months (median = 10 months, IQR =6.5 -17.5). There were 46.2% (40.4 -52.1) boys among children with AE.

63.7% (57.9 -69.2) of the patients initially sought medical assistance due to AE in less than 6 months after vaccination, 13, 5% (9.8 - 18.0) children - after 6 - 12 months, and after year or more - 22.4% (17.6 -27.6) children.

Conclusions: Level of AE in Moscow is low enough. Quality monitoring of AE allows provide effective management of adverse events through organization of measures of control, diagnostics and treatment.