Immunogenicity and Safety PCV-20 of the Vaccine Administered During an Acute Febrile Illness in Adults

Inclusion criteria : * History of body temperature ≥ 38°C measured at least twice prior to randomization (Randomization must be performed as soon as possible on a febrile patient or 72 hours after apyrexia at the latest) * Having at least one comorbidity that defines patients as medium or high risk for pneumococcal invasive infection: * Medium risk: Cyanogenic congenital heart disease; chronic heart failure; chronic respiratory failure; chronic obstructive pulmonary disease; emphysema; severe asthma under chronic treatment; chronic renal failure; chronic liver disease; diabetes mellitus treated; Osteo-meningeal leak or cochlear implant; Age \> 65 years old. * High risk : Hypo or asplenic people; hereditary immunodeficiency syndromes; people living with HIV; solid organ transplanted; People under immunosuppressors (corticosteroids, biotherapy) for an auto-immune or an inflammatory chronic disease; patients with nephrotic syndrome * Hospitalization for \> 24 hours long * Social security affiliation * Signed informed consent Exclusion criteria : * Patient unable to give informed consent * Curators, wardship * History of previous vaccination with PCV-7 or PCV-13 or PCV-20 * History of PPV-23 in the previous year * Patient having received another vaccination within one month prior to inclusion or planning another vaccination in the month after inclusion except for Influenza vaccine. * Patient with history of bone marrow transplantation * Patient with haematological malignancies * Patient under chemotherapy for solid tumor or with a history of chemotherapy in the past three months * Patient treated with Rituximab currently or in the past 6 months * Patient with Sequential Organ Failure Assessment (qSOFA ) score ≥ 2 at randomization (acute severe febrile illness) * Patient hospitalized in an Intensive Care Unit * Pregnancy * Breastfeeding woman * Recipients of polyclonal gammaglobulins in the past three months * Inability to follow the protocol * Bleeding disorder contra-indicating intramuscular injection according to the investigator * History of allergy to PCV-20 or vaccine-related components. * S. pneumoniae infection with laboratory confirmation (blood culture, culture from a sterile site, urinary or Cerebrospinal fluid antigens, sputum culture with \> 10\^7 colony forming unit (CFU)/mL) being the cause of the current hospitalization