Use of BCG Vaccine as a Preventive Measure for COVID-19 in Health Care Workers

The disease promoted by coronavirus (COVID-19) is caused by Severe Acute Respiratory Syndrome (SARS) caused by Coronavirus type 2 (CoV2), being the first cases identified in December 2019 in China after exposure to the animal market in Wuhan city, China. From the first case to the present day, the COVID-19 epidemic has been identified in 185 countries, with the notification of 2,666,154 cases and 186,144 deaths. In Brazil, more than 45,757 cases and 2,906 confirmed deaths by COVID-19 have been confirmed (Visualized on Apr 23 2020). In our country, to date, testing for COVID-19 occurs only in severe cases and few centers offer the service to health care workers, a population at high risk of infection. BCG is a vaccine produced from a live attenuated strain derived from a Mycobacterium bovis isolate and is widely used worldwide as a tuberculosis (TB) vaccine, but there are studies demonstrating non-specific immunotherapeutic mechanisms of this vaccine that signal a possible relationship with the lowest morbidity and mortality associated with COVID-19 infections worldwide. The present study aims to analyze the role of BCG in the prevention of SARS-CoV-2 infection and also in the occurrence of severe forms of COVID-19 in addition to evaluating the immune response mediated by this vaccine in voluntary health care workers.

Study detailed description can be seen on the protocol attached.

Eligibility Criteria:
Inclusion Criteria:

1. Individuals aged 18 ≥, male or female, not infected with SARS-CoV-2
2. Agreement to participate in the study by signing the Free Informed Consent (FIC)
3. Not being pregnant (in case of women able to become pregnant)
4. Have not received a specific vaccine against COVID-19 or, if vaccinated against SARS-CoV-2, have received the complete immunization schedule only with vaccines approved by ANVISA and implemented by the National Immunization Program, (including the second dose) within a minimum of 15 days prior to the date of inclusion in the study
5. If the participant have not received a specific vaccine against COVID-19 approved by ANVISA, be aware and agree to be able to receive them only 15 days after the intervention proposed in this study

Exclusion Criteria:

1. Professionals with a history of SARS-CoV-2 confirmed infection through RT-PCR or who have already presented clinical and molecular diagnosis of COVID-19 prior to the study
2. Individuals who have not underwent confirmatory tests for COVID-19
3. Breastfeeding
4. Individuals with primary or acquired immunodeficiency
5. Individuals affected by malignant neoplasms
6. Patients treated with high-dose corticosteroids (equivalent to the prednisone dose of 20 mg/day or more) for more than two weeks
7. Patients using other immunosuppressive therapies (antineoplastic chemotherapy, radiotherapy, among others)
8. Individuals with autoimmune diseases
9. Dermatological conditions at the vaccine site or generalized
10. Individuals under treatment for active tuberculosis
11. Individuals with a history of previous tuberculosis treatment
12. Individuals with febrile symptoms \[body temperature ≥ 37.5 celsius degree (ºC) in the last 48h\]
13. Participation in other prevention clinical trials for COVID-19 (vaccines already approved by ANVISA for use by the National Immunization Program are not included in this item)
14. Report of vaccination with live microorganism administered in the month prior to randomization
15. Require that, if another vaccination with live microorganism is required, it is administered in the month following randomisation (If the other live vaccine can be administered on the same day, this exclusion criterion does not apply)
16. Known anaphylactic reaction to any ingredient in BCG vaccine
17. Adverse reaction prior to BCG vaccine \[significant local reaction (abscess) or suppurative lymphadenitis\]
18. BCG vaccine administered in the last year