A Real-world Evidence Study of BNT162b2 mRNA Covid-19 Vaccine Among Children in Brazil

A Real-world Evidence Study of BNT162b2 mRNA Covid-19 Vaccine Among Children Aged 5 to 11 Years in Brazil

The present test-negative design study aims to estimate the real-world effectiveness of Pfizer-BioNTech BNT162b2 mRNA vaccine on symptomatic SARS-CoV-2 infection and its consequences among children aged 5 to 11 years in the city of Toledo in Southern Brazil.

Individuals aged 5 to 11 years who seek the public healthcare system with symptoms suggestive COVID-19 will be enrolled. Participants with a positive reverse transcriptase polymerase chain reaction (RT-PCR) test for SARS-CoV-2 will be classified as cases, and those with negative RT-PCR test for SARS-CoV-2 will be classified as controls. Cases will be followed-up for a period of 3 months by means of structured telephone interviews.

Inclusion Criteria:

• Age between 5 and 11 years;
• Resident of Toledo city;
• Seeking care in the public healthcare system with symptoms suggestive of COVID-19 defined as follows: 1) ARI symptoms (nasal congestion, rhinorrhea, anosmia, sore throat, hoarseness, new or increased-from-baseline cough, sputum production, dyspnea, wheezing, myalgia) OR 2) Admitting diagnosis suggestive of ARI (pneumonia, upper respiratory infection, bronchitis, influenza, cough, asthma, viral respiratory illness, respiratory distress, AND/OR respiratory failure).
• Nasal or nasopharyngeal sample for SARS-CoV-2 test obtained as standard of care.

Exclusion Criteria:

• SARS-CoV-2-directed antiviral treatment within the past 30 days;
• COVID-19 monoclonal antibody therapy within the past 90 days;
• COVID-19 convalescent serum therapy within the past 90 days;
• Failure to perform RT-PCR for diagnosis of SARS-CoV-2 infection.