Definitions 1. Uncomplicated influenza: influenza presenting with fever, coryza, generalised symptoms (headache, malaise, myalgia, arthralgia) and sometimes gastrointestinal symptoms, but without any features of complicated influenza. 2. Complicated influenza: influenza requiring hospital admission and/or with symptoms and signs of lower respiratory tract infection (hypoxaemia, dyspnoea, lung infiltrate), central nervous system involvement and/or a significant exacerbation of an underlying medical condition. 3. Risk factors for complicated influenza: chronic neurological, hepatic, renal, pulmonary and chronic cardiac disease  diabetes mellitus  severe immunosuppression  age over 65 years  pregnancy (including up to two weeks post partum)  children under six months of age  morbid obesity  (BMI ≥40) For full details refer to as the Green ‘Immunisation against infectious disease’, known Book (4). 4. Severe immunosuppression: Examples of severe immunosuppression relevant to this guidance are given below. Degrees of immunosuppression are difficult to quantify and individual variation exists, therefore this list is not comprehensive: severe primary immunodeficiency  current or recent (within six months) chemotherapy or radiotherapy for malignancy  solid organ transplant recipients on immunosuppressive therapy  bone marrow transplant recipients currently receiving immunosuppressive treatment,  or who received it within the last 12 months patients with current graft-versus-host disease  patients currently receiving high dose systemic corticosteroids (equivalent to  ≥40 mg prednisolone per day for >1 week in an adult, or for week in a ≥ 2mg/kg/day ≥1 child), and for at least three months after treatment has stopped HIV infected patients with severe immunosuppression or <15% of total  (CD4<200/μl lymphocytes in an adult or child over or <15% of total lymphocytes five; CD4< 500/μl in a child aged one to five; expert clinical opinion in a child aged under one) patients currently or recently (within six months) on other types of  immunosuppressive therapy or where the specialist regards them as patient’s severely immunosuppressed
Definitions 1. Uncomplicated influenza: influenza presenting with fever, coryza, generalised symptoms (headache, malaise, myalgia, arthralgia) and sometimes gastrointestinal symptoms, but without any features of complicated influenza. 2. Complicated influenza: influenza requiring hospital admission and/or with symptoms and signs of lower respiratory tract infection (hypoxaemia, dyspnoea, lung infiltrate), central nervous system involvement and/or a significant exacerbation of an underlying medical condition. 3. Risk factors for complicated influenza:  chronic neurological, hepatic, renal, pulmonary and chronic cardiac disease  diabetes mellitus  severe immunosuppression  age over 65 years  pregnancy (including up to two weeks post partum)  children under six months of age  morbid obesity (BMI ≥40) For full details refer to ‘Immunisation against infectious disease’, known as the Green Book (4). 4. Severe immunosuppression: Examples of severe immunosuppression relevant to this guidance are given below. Degrees of immunosuppression are difficult to quantify and individual variation exists, therefore this list is not comprehensive:  severe primary immunodeficiency  current or recent (within six months) chemotherapy or radiotherapy for malignancy  solid organ transplant recipients on immunosuppressive therapy  bone marrow transplant recipients currently receiving immunosuppressive treatment, or who received it within the last 12 months  patients with current graft-versus-host disease  patients currently receiving high dose systemic corticosteroids (equivalent to ≥40 mg prednisolone per day for >1 week in an adult, or ≥ 2mg/kg/day for ≥1 week in a child), and for at least three months after treatment has stopped  HIV infected patients with severe immunosuppression (CD4<200/μl or <15% of total lymphocytes in an adult or child over five; CD4< 500/μl or <15% of total lymphocytes in a child aged one to five; expert clinical opinion in a child aged under one)  patients currently or recently (within six months) on other types of immunosuppressive therapy or where the patient’s specialist regards them as severely immunosuppressed
PHE_guidance_on_use_of_antiviral_agents_for_the_treatment_and_prophylaxis_of__Vm9xXKz.docx