Page 50 - MDJ 2022 Jan-Jun, Volume 45 Number 1

Masood / Rizwan / Rizwan / Mujtaba / Farooqi / Zaib / Butt

BCG decreased the viral load of influenza A virus in mice, 19 patients have been reported to have medical
an impact reliant on macrophages, while it likewise comorbidities.
protected from herpes simplex infection type 2 in a
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controlled murine model with infant mice. Moreover, In our study we found that the BCG vaccination
BCG-induced trained immunity manifested protective is not associated with severity of symptoms of a COVID-
effects in a model of controlled experimental viral 19 infection. In the year between April 2017 – June 2018,
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infections in humans. BCG, which can stay alive in the a professor of Experimental Internal Medicine, Professor
human skin for a while, triggers not just explicit memory Mihai Netea, and his team in the Netherlands, conducted a
B and T cells but also causes epigenetic reprogramming in study in which a group of healthy volunteers received the
human monocytes, followed by functional reprogramming BCG vaccine. During the COVID-19 pandemic these
and protection against unrelated viral infections, with IL-1 participants were called again to check the effect of the
playing a significant role as a modulator of trained immune vaccine on the symptoms attributed to coronavirus
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responses. It was also shown in a randomised placebo- infection. Those who received the vaccine did not have
controlled examination that the BCG vaccine protects more symptoms, did not become more seriously ill, and
against an experimental infection with an attenuated strain did not show a higher tendency to fall sick during the first
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of yellow fever virus. wave of the COVID-19 pandemic in the Netherlands.
The most common symptoms in our study were fever,
This information prompted the hypothesis that tiredness and dry cough, similar to the study done by
BCG inoculation may likewise help against SARS-CoV-2, Moorlag et al. (2020). In his study, 8.3 % of the
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and a few huge clinical preliminaries are in progress. participants had an incidence of extreme fatigue, a
Epidemiological examinations appear to support this common symptom of COVID-19.
theory by revealing lower rates of infection and mortality
in nations with a childhood BCG immunisation BCG immunisation may become viable only once
programme. The result of our study showed insignificant a large portion of the population is made resistant to the
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correlation between the BCG vaccine and COVID-19 infection. In other words, the spread of the infection might
infection (p ≥ 0.05). Therefore, our hypothesis that BCG ease when there is “herd immunity” that prevents the
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vaccine causes a significant reduction of spread of infection from spreading effectively over the population.
coronavirus is rejected. Our study is similar to the study Currently, there are 3 active clinical preliminaries working
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conducted by Kirov et al. (2020) and Szigeti et al. to decide whether BCG immunisation protects healthcare
(2020), who also showed no correlation between BCG workers (HCWs) during the COVID-19 pandemic;
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vaccination policy and COVID-19 infection. In addition, BRACE is a stage III randomised controlled trial directed
the World Health Organisation (WHO) report distributed in Australia that will select up to 4170 HCWs to assess
on 12 April 2020 expressed that there is no current proof whether the BCG vaccine lessens the frequency and
th
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that BCG vaccine protects against COVID-19. Strong severity of COVID-19.
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proof ought to be found through planned assessment in
randomised controlled trials. In contradiction to the There are a few limitations in our study. Firstly,
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previous statement, Berg’s (2020) analysis showed that the sample size in our pilot study was very small; a very
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the BCG vaccination is associated with the flattening of small number of people were willing to participate and
the curve in the spread of COVID-19. Hensel’s (2020) some of the participants were not certain about their
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results are similar to Berg’s (2020). vaccination status. Secondly, most of the people in
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Pakistan are vaccinated with BCG so we lacked an
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Age is a major risk factor in COVID-19. A unvaccinated group for comparison. In all national policies,
study found that vaccination of adults ≥ 65 years of age BCG is given early in life, commonly after the child is born.
with BCG prevented acute upper respiratory tract It is not clear whether BCG vaccinations are successful
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infection, and there is an active clinical trial vaccinating when given to adults. It is similarly unclear how long the
adults aged > 65 years with BCG to boost immunity. The BCG vaccine may provide immunity to COVID-19 despite
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predominance of comorbidities — for example diabetes, the fact that it is viable against tuberculosis and lung
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cardiovascular illness, constant respiratory sickness and cancer for quite a few years. Additionally, it is unclear
malignancy — is increasing in low to middle income whether BCG may have any unfavourable effects when
countries. In 2019, non-insulin dependent diabetes given to those already infected with COVID-19.
mellitus prevalence among adults was 11 % in Asian
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nations and 6 % in Europe. The World Health There is a systematic review with evidence and
Organisation gauges a higher cardiovascular sickness risk low to moderate risk of bias that BCG vaccination prevents
in Asian areas compared to in European and North respiratory infections like influenza and pneumonia of all
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American regions. In our study, only 6 patients out of 50 kinds and in older populations as well. Our study
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had hypertension and 1 had diabetes. In a study done by concluded that there is no significant analogy between
Moorlag et al. (2020), out of 266 BCG vaccinated BCG and COVID-19 and there is no current evidence that
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patients, only 4 hypertensive and 3 diabetic participants the BCG vaccine protects against COVID-19. More
were present. This shows that a very few of the COVID- research with larger sample size is required to study the
magnitude and span of the non-specific effects of the BCG
vaccine on COVID-19. Better evidence ought to be
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