Before revision:  The vaccination rate fell from 92\% to 2\% . I compare the numbers of COVID-19 cases and hospitalizations for cohorts born just before and just after that change .
After revision:  The vaccination rate fell from 92\% to 2\% , thus allowing us to estimate the BCG's effect without all the biases associated with cross-country comparisons. Numbers of COVID-19 cases and hospitalizations for cohorts born just before and just after that change .