Use of plasma of cured person to treat patient with severe covid-19

INTERVENTION: 40 patients will be treated with convalescent plasma, whose outcomes will be compared with those from a control group of 80 non‐transfused patients with the same disease. (total of 120 participants). Convalescent plasma to treat patients with covid‐19 dose: 600 mL/day for three days Outcomes will be compared with that observed in control group (no plasma transfusiona) A12.207.152.693 CONDITION: A00‐B99 Coronavirus infection, transfusion, C23, A00‐B99, Coronavirus OC43, Human. PRIMARY OUTCOME: Survival rate in each group on day 30 of orotracheal intubation or diagnosis of respiratory failure. SECONDARY OUTCOME: Time (in days) of mechanical ventilation in both study groups. Time (in days) of hospital stay in the two study groups. Time (in days) of persistence in oro and nasopharynx of covid‐19 and viremia in groups submitted to conventional treatment and in the group treated with plasma. Complication index of plasma transfusion in the transfused group. INCLUSION CRITERIA: Infection confirmed by SARS‐CoV‐2 (RT‐PCR of oro / nasopharyngeal material, or by the detection of IgM‐class anti‐SARS‐CoV‐2 antibody, or IgA, associated with a clinical picture suggestive of the disease). respiratory failure: patient on mechanical ventilation or with satO2 ? 93% in room air. Maximum of 10 days from the onset of symptoms. Age between 18 and 80 years. Formal agreement (signing the free and informed consent form‐ FICF‐ by the participant or by a member of his family) to participate in the study (it is worth remembering that the majority, or the totality, of the patients will not be in clinical conditions to agree or not to the proposal to participate in the study, therefore, the possibility of acceptance by first‐degree relative, or second‐degree relative in the absence of the former).