Showing posts from June, 2020
A preprint denying the BCG hypothesis with the data of Sweden Here comes another preprint denying the BCG hypothesis by comparing age group in the same country, Sweden, this time. This method is flawed as it ignores the external immunity effect which is much larger than the individual immunity effect. The BCG vaccine does not protect against COVID-19. Evidence from a natural experiment in Sweden https://arxiv.org/abs/2006.05504 This preprint concludes that the BCG vaccine has no effect against COVID-19 since there is no difference in cases per 1,000 inhabitants before and after 1975 when Sweden stopped its universal BCG vaccination program. However, this preprint also says it is hard to conclude from the death tolls as the mortality rate increases by age. Here is the figure of this preprint about the deaths per 1,000 inhabitants. Please look at this carefully. Don't you notice that the mortality rate is not changing from 1972 to 1978 birth year? Isn't it strange?