SOME REMARKS ON THE STATE OF THE BCG STRAIN PASTEUR 1173 P₂ C USED FOR VACCINE PRODUCTION

Tran Thi Thao, Tran The Trong, Tan Thi Ngoc Bich, Mai Nguyet Thu Hong, Ly Phi Phung

Pasteur Institute in HoChiMinh City

Summary

BCG vaccine production in Pasteur Institute in HoChiMinh City has to maintain its quality and stable viability among batches. The quality control on 286 lots of BCG vaccine produced, showed the following results:

1. Through 6 passages from one ampule of BCG strain:

All batches of BCG vaccine prepared from the 1^st to the 6^th passages reached to the NCA and WHO criteria, including:

§ Fresh BCG vaccine:

The viability is from 14.79 to 15.66 x 10⁶ UV BCG/ mg.

§ After being freeze-dried:

It is from 2.79 to 3.38 x 10⁶ UV BCG/ mg.

§ At + 4⁰C after one month:

It is from 2.76 to 3.18 x 10⁶ UV BCG/ mg.

§ % of survival after being freeze-dried.

It is from 19.39 % to 22.63 %.

§ % of heat stability:

It is from 37.66 % to 47.79 %.

2. BCG mass is divided into 3 ranges according to moist weight: <12g, 12g-14g, and >14g. The result of these 3 groups of samples, from the 1^st to the 6^th passage, satisfied all the requirements, however the lowest oscillation of colonies forming units between each batch, seems to be located in 12g to 14g.