Is there evidence that BCG vaccination has non-specific protective effects for COVID 19 infections or is it an illusion created by lack of testing?

Abstract

The goal of this paper is to showcase that the COVID-19 disease pattern is evolving and to study the relationship between mandatory BCG policy and caseload/million or death/per million. We analyze seven recent publications on the impact of BCG vaccinations on the development of COVID19 illness and extend presented findings using the latest data from April 10, 2020. We analyze data from 98 countries and we extend existing models by adding the dimension of COVID-19-related testing conducted by the analyzed countries. Similarly to prior studies, we find that COVID-19 attributable case and death incidences across countries share a relationship with a country's BCG vaccination inclusion in the national immunization program when testing is not taken into consideration. However, this relationship vanishes when we add the dimension of testing. We observe that case and death incidences conditional on testing do not get affected by the countries' BCG vaccination inclusion in the national immunization program. Therefore, we show that there is no statistical evidence to support the assertion that inclusion of BCG vaccination in national immunization program (NIP) has any impact of COVID 19 infections (cases) or mortality.

Mandated Bacillus Calmette-Guérin (BCG) vaccination predicts flattened curves for the spread of COVID-19

“…Moreover, they are massively influenced by reporting biases (including the availability of diagnostic testing), which can be both sizable and variable across countries. The same reservation applies to fatality rate (total deaths/total cases) (18,26,(28)(29)(30)(31)(32) since the reporting biases are likely to be higher for confirmed cases than for deaths. We circumvented these problems in three ways.…”

Mandated Bacillus Calmette-Guérin (BCG) vaccination predicts flattened curves for the spread of COVID-19

“…Moreover, they are massively influenced by reporting biases (including the availability of diagnostic testing), which can be both sizable and variable across countries. The same reservation applies to fatality rate (total deaths/total cases) ( 18, 26, 28–32 ) since the reporting biases are far more likely and cross-nationally variable for the confirmed cases than for the deaths. We circumvented these problems in three ways.…”

Identification of similar epitopes between severe acute respiratory syndrome coronavirus‐2 and Bacillus Calmette–Guérin: potential for cross‐reactive adaptive immunity

“…The role of Bacillus Calmette-Gu erin (BCG) vaccination in the prevention of SARS-CoV-2 infection and in the epidemiology of COVID-19 has been frequently implicated. 1 BCG is an attenuated Mycobacterium bovis strain, a species of the Mycobacterium tuberculosis complex, and is used worldwide for vaccination against M. tuberculosis. Interestingly, BCG appears to have multiple effects.…”