Exercising caution in correlating COVID-19 incidence and mortality rates with BCG vaccination policies due to variable rates of SARS CoV-2 testing

Janine Hensel; Daniel J McGrail; Kathleen M McAndrews; Dara Dowlatshahi; Valerie S LeBleu; Raghu Kalluri

Our analyses also confirmed the association with implementing universal BCG policy with countries with high TB incidence ( Figure 3A) . In the countries with universal BCG policy in the past, the year in which the policy was discontinued was available for 14 out of the 18 countries in this group. The number of COVID-19 cases per 1M inhabitants was not significantly different when comparing countries that had discontinued the universal policy for at least 20 years and countries that had discontinued the universal policy less than 20 years ago ( Figure 3B) . The mortality associated with COVID-19 was not impacted whether the policy for universal BCG vaccine was discontinued less than or more than 20 years ago ( Figure 3B ). In the countries with current universal BCG policy and with available data, there was no correlation observed in the total COVID-19 cases per 1M inhabitant or percent mortality per total COVID-19 cases, and the time since implementation of the universal BCG policy (Figure 3C ). There were also no significant correlation observed in the percent mortality per total COVID-19 cases and the time since the first confirmed COVID-19 cases in countries that never had a universal BCG policy (Figure 3D) , or had a universal BCG policy in the past (Figure 3E) , or have a current universal BCG policy ( Figure 3F ).