1) Patients with an underlying medical condition (“classic risk groups”): Start therapy < 48 hours after developing fever:
- Patients with an abnormality and an impairment of the function of the respiratory tract/lungs. This includes, among others, patients with asthma also if younger than 18 years of age.
- Patients having a serious, acute or chronic, heart condition
- Patients with diabetes mellitus.
- Patients with Chronic Kidney Disease (including patients on haemodialysis or chronic ambulatory peritoneal dialysis (CAPD), and persons who have undergone a kidney transplant).
- Patients who have had a recent bone marrow or organ transplant.
- Intellectually impaired persons living in an intramural setting.
- Persons with an impaired resistance to infections (see below)
- Personen 60 years of age and older.
2) Patients with a severely impaired immune system who are at increased risk for complications of flu.Start therapy < 48-72 hours after developing fever:
- Patients with a- or hypogammaglobulinaemia.
Eg: Bruton’s X-linked agammaglobulinaemia; common variable immunodeficiency; and hypogammaglobulinaemia secondary to chronic lymphatic leukemia; Morbus Kahler stages II-III; treatment with anti-CD20 Mab such as Rituximab. - Patients having an impaired cellular immune system.
Eg: after an allogenic bone marrow transplant; Morbus Hodgkin (including the 1st 5 years after treatment); extended lymphopenia after chemotherapy or after treatment with Mab such as ATG and OKT3; extended use of glucocorticosteroids (or cumulative dosis equivalent to 1000 mg prednison) or methotrexate; HIV-patients; use of anti-TNFalpha Mab (Infliximab, Etanercept or Adalimumab) in combination with methotrexate; and patients who undergo an immune modulating or suppressive therapy following a solid organ transplant.
3) Children younger than 2 years of age. Start therapy < 48 hours after developing fever:
- NB: Children < 3 months should be treated under medical supervision in hospital
4) Persons with a more severe/complicated course of disease and/or who are admitted to hospital. Therapy can be started also after 48 hours after developing fever:
- Persons (previously healthy) with flu like symptoms in which the flu infection evolves in an uncharacteristic severe manner and/or is complicated and hospital admittance becomes necessary.
- Persons developing a complication. Mostly secondary bacterial bronchopneumonia or pneumonia or a viral pneumonia.
5) Pregnant women in their third trimester of pregnancy. Start therapy < 48 hours after developing fever.