inclusion criteria: patients between 18 and 675 years old included in the corimuno-19 cohort patients belonging to one of the 2 following groups group 1: 60 patients not requiring icu at admission with moderate and severe pneumopathy according to the who criteria of severity of covid pneumopathy, meeting all of the 2 following criteria: respiratory symptoms with radiological findings of pneumonia severe pneumonia requiring ≥ 5l/min of oxygen to maintain spo2 >97% group 2: 60 patients requiring icu based on criteria of severity of covid pneumopathy. respiratory failure and requiring mechanical ventilation vasopressive support vaccinated against meningococcal infections within 3 years prior to, or at the time of, initiating eculizumab to reduce the risk of meningococcal infection (n meningitidis) [(bexsero® (2 injections with a minimum of 1 month interval) + menveo@ or niminrex® ) and daily antibiotics (oracilline®)]. if vaccination cannot be confirmed or if the patient cannot receive it, the participant should receive prophylactic antibiotics against meningococcal infection prior to initiating eculizumab treatment and for at least 3 months from the last infusion of eculizumab. female patients of childbearing potential and male patients with female partners of childbearing potential must follow protocol-specified guidance for avoiding pregnancy while on treatment and for 8 months after last dose of eculizumab. 5- body weight ≥40 kg 6-patient and/or alternatively by next-of-kin must be willing and able to give written informed consent according to the applicable regulations including emergency and intensive care contexts

inclusion criteria: patients between 18 and 675 years old included in the corimuno-19 cohort patients belonging to one of the 2 following groups group 1: 60 patients not requiring icu at admission with moderate and severe pneumopathy according to the who criteria of severity of covid pneumopathy, meeting all of the 2 following criteria: respiratory symptoms with radiological findings of pneumonia severe pneumonia requiring ≥ 5l/min of oxygen to maintain spo2 >97% group 2: 60 patients requiring icu based on criteria of severity of covid pneumopathy. respiratory failure and requiring mechanical ventilation vasopressive support vaccinated against meningococcal infections within 3 years prior to, or at the time of, initiating eculizumab to reduce the risk of meningococcal infection (n meningitidis) [(bexsero® (2 injections with a minimum of 1 month interval) + menveo@ or niminrex® ) and daily antibiotics (oracilline®)]. if vaccination cannot be confirmed or if the patient cannot receive it, the participant should receive prophylactic antibiotics against meningococcal infection prior to initiating eculizumab treatment and for at least 3 months from the last infusion of eculizumab. female patients of childbearing potential and male patients with female partners of childbearing potential must follow protocol-specified guidance for avoiding pregnancy while on treatment and for 8 months after last dose of eculizumab. 5- body weight ≥40 kg 6-patient and/or alternatively by next-of-kin must be willing and able to give written informed consent according to the applicable regulations including emergency and intensive care contexts

inclusion criteria: 1. patients between 18 and 675 years old included in the corimuno-19 cohort 2. patients belonging to one of the 2 following groups - group 1: 60 patients not requiring icu at admission with moderate and severe pneumopathy according to the who criteria of severity of covid pneumopathy, meeting all of the 2 following criteria: - respiratory symptoms with radiological findings of pneumonia - severe pneumonia requiring ≥ 5l/min of oxygen to maintain spo2 >97% - group 2: 60 patients requiring icu based on criteria of severity of covid pneumopathy. - respiratory failure and requiring mechanical ventilation - vasopressive support 3. vaccinated against meningococcal infections within 3 years prior to, or at the time of, initiating eculizumab to reduce the risk of meningococcal infection (n meningitidis) [(bexsero® (2 injections with a minimum of 1 month interval) + menveo@ or niminrex® ) and daily antibiotics (oracilline®)]. if vaccination cannot be confirmed or if the patient cannot receive it, the participant should receive prophylactic antibiotics against meningococcal infection prior to initiating eculizumab treatment and for at least 3 months from the last infusion of eculizumab. 4. female patients of childbearing potential and male patients with female partners of childbearing potential must follow protocol-specified guidance for avoiding pregnancy while on treatment and for 8 months after last dose of eculizumab. 5- body weight ≥40 kg 6-patient and/or alternatively by next-of-kin must be willing and able to give written informed consent according to the applicable regulations including emergency and intensive care contexts

inclusion criteria: 1. patients between 18 and 675 years old included in the corimuno-19 cohort 2. patients belonging to one of the 2 following groups - group 1: 60 patients not requiring icu at admission with moderate and severe pneumopathy according to the who criteria of severity of covid pneumopathy, meeting all of the 2 following criteria: - respiratory symptoms with radiological findings of pneumonia - severe pneumonia requiring ≥ 5l/min of oxygen to maintain spo2 >97% - group 2: 60 patients requiring icu based on criteria of severity of covid pneumopathy. - respiratory failure and requiring mechanical ventilation - vasopressive support 3. vaccinated against meningococcal infections within 3 years prior to, or at the time of, initiating eculizumab to reduce the risk of meningococcal infection (n meningitidis) [(bexsero® (2 injections with a minimum of 1 month interval) + menveo@ or niminrex® ) and daily antibiotics (oracilline®)]. if vaccination cannot be confirmed or if the patient cannot receive it, the participant should receive prophylactic antibiotics against meningococcal infection prior to initiating eculizumab treatment and for at least 3 months from the last infusion of eculizumab. 4. female patients of childbearing potential and male patients with female partners of childbearing potential must follow protocol-specified guidance for avoiding pregnancy while on treatment and for 8 months after last dose of eculizumab. 5- body weight ≥40 kg 6-patient and/or alternatively by next-of-kin must be willing and able to give written informed consent according to the applicable regulations including emergency and intensive care contexts