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[INCREASE IN THE NUMBER OF INFANTS WITH KOCH PHENOMENON AFTER BCG VACCINATION]
Purpose:
To investigate the trends in the number of infants diagnosed with Koch phenomenon after BCG vaccination following the change in the timing of the vaccination.
Method:
We extracted and analyzed data from infants aged ≤ 1 year diagnosed with latent tuberculosis infection (LTBI) or active tuberculosis, registered in the Japanese tuberculosis surveillance system, from May 2012 to the end of the year, and from May 2013 to the end of the year.
Result:
There was no increase in active tuberculosis cases between the two periods (5 patients each). However, the number of infants with LTBI doubled (45 to 90), presumably because Koch phenomenon developed after BCG vaccination.
Conclusion:
After changing the timing of vaccination, the number of infants experiencing Koch phenomenon appears to have increased. However, more in-depth analysis of this finding is required.
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