* known allergy to (components of) bcg or serious adverse events to prior bcg administration; * known previous, active or latent infection with mycobacterium tuberculosis or other mycobacterial species * fever (\>38 c) within past 24 hours; * previous confirmed covid-19 (positive test - pcr or antibody); * suspicion of active viral or bacterial infection * severely immunocompromised subjects * self-reported hiv infection * self-reported pregnancy; * active solid or non-solid malignancy or lymphoma within the prior two years; * contraindications for live attenuated vaccine administration. * not having a mobile phone.

* known allergy to (components of) bcg or serious adverse events to prior bcg administration; * known previous, active or latent infection with mycobacterium tuberculosis or other mycobacterial species * fever (\>38 c) within past 24 hours; * previous confirmed covid-19 (positive test - pcr or antibody); * suspicion of active viral or bacterial infection * severely immunocompromised subjects * self-reported hiv infection * self-reported pregnancy; * active solid or non-solid malignancy or lymphoma within the prior two years; * contraindications for live attenuated vaccine administration. * not having a mobile phone.

- known allergy to (components of) bcg or serious adverse events to prior bcg administration; - known previous, active or latent infection with mycobacterium tuberculosis or other mycobacterial species - fever (>38 c) within past 24 hours; - previous confirmed covid-19 (positive test - pcr or antibody); - suspicion of active viral or bacterial infection - severely immunocompromised subjects - self-reported hiv infection - self-reported pregnancy; - active solid or non-solid malignancy or lymphoma within the prior two years; - contraindications for live attenuated vaccine administration. - not having a mobile phone.

- known allergy to (components of) bcg or serious adverse events to prior bcg administration; - known previous, active or latent infection with mycobacterium tuberculosis or other mycobacterial species - fever (>38 c) within past 24 hours; - previous confirmed covid-19 (positive test - pcr or antibody); - suspicion of active viral or bacterial infection - severely immunocompromised subjects - self-reported hiv infection - self-reported pregnancy; - active solid or non-solid malignancy or lymphoma within the prior two years; - contraindications for live attenuated vaccine administration. - not having a mobile phone.