Does TB Vaccination Reduce COVID-19 Infection?: No Evidence from a Regression Discontinuity Analysis

Masao Fukui; Kohei Kawaguchi; Hiroaki Matsuura

We collected information on year of introduction and termination of the BCG vaccination and types of strains used from the BCG World Atlas (Zwerling et al., 2011) . Then, we matched them with country-age-level COVID-19 confirmed case statistics from information available from each government's website. This resulted in a data set over 17 countries with relevant information: Australia, Colombia, the Czech Republic, Denmark, Finland, India, Japan, Korea, Latvia, New Zealand, Romania, Singapore, Spain, Sweden, Switzerland, Thailand, and Vietnam. Exact age-level case statistics were available in Colombia, the Czech Republic, Thailand, Vietnam, and Singapore. In remaining countries, only a 10-year age-group level data were available. Of these 17 countries, the Japan strain or Russia/Bulgaria strain have been used in Japan, Thailand, Colombia, and Latvia. In Colombia, case statistics at the nationality level are available. Hence, we focus on people with Colombian nationality in Colombia data, whereas all residents not differentiated by nationality are included in the other countries' data. The immunization rate of infants at each year is available from the World Health Organization (WHO) website. 3 We refer to this in the figure, even though this does not necessarily correspond to the immunization rate at each age as of 2020.