Transcript Slide 1
INFLUENZA COMPLICATIONS Influenza complications • Bacterial superinfections – bacterial pneumonia – croup – respiratory disorders • Decompensation of chronic diseases – pulmonary disease – heart disease – renal insufficiency – metabolic disease Nicholson KG. Semin Respir Infect 1992; 7: 26–37. Influenza – respiratory complications • Upper respiratory tract infection (URTI) – otitis media – sinusitis • Lower respiratory tract infection (LRTI) – exacerbation of asthma/chronic obstructive pulmonary disease (COPD) – croup, bronchiolitis – primary viral pneumonia (rare*) – secondary bacterial pneumonia *5–10% of pneumonia is an influenza complication Influenza complications • • • • • • • • • • • • • • • Primary viral pneumonia Bacterial secondary pneumonia Tracheobronchitis Bronchiolitis Congestive heart failure Myocarditis, pericarditis Complications of sinus, middle ear, musculature Reye’s syndrome – in children Ketoacidosis – in diabetics Acute viral encephalitis – in children Guillain Barre syndrome Gastrointestinal bleeding – in children Decompensation of pre-existing pathology Excess mortality Possible association with prenatal exposure and schizophrenia Groups at higher risk of complications • Elderly (> 60 years of age), especially in residential care units • Children and teenagers (6 months–18 years of age) receiving long-term aspirin therapy • Pregnant women belonging to high-risk groups • Patients with: – – – – – – chronic respiratory disease, e.g. asthma, COPD chronic heart disease chronic metabolic disease, e.g. diabetes mellitus immunosuppression due to treatment or disease, e.g. HIV haematological disorders chronic renal failure Palache AM. Influenza subunit vaccine - ten years experience. Eur J Clin Res 1992; 3: 117–38. Age distribution of respiratory complications Respiratory complications (%) 80 60 40 20 0 0–4 5–9 10–19 20–39 40–49 50–59 50–69 > 70 Age groups (year) Betts FR et al. In: Mandell GL et al., eds. Principles and Practice of Infectious Diseases. 3rd Edn. New York: Churchill Livingstone; 1990: 1306–25. Influenza complications in children • Higher fever than in adults • Higher incidence of coryza, otitis media and gastrointestinal manifestations • Influenza may present as croup or bronchiolitis • Higher incidence of drowsiness and delirium • Complications like myositis and pneumonia are more frequent Nicholson KG. Semin Respir Infect 1992; 7: 26–37. Severe symptoms in children Bronchiolar, pulmonary signs 30% Vomiting, diarrhoea 40% Pharyngitis 50% Fever, rhinitis 90% Kilbourne ED. Influenza. New York: Plenum Medical Book Company; 1987: 157–66. Influenza in children with asthma and other chronic medical conditions • Retrospective cohort study, Tennessee Medicaid program (1973–1993) • Children under 15 with medically treated asthma or chronic medical conditions Yearly excess hospitalisation for cardiopulmonary disease due to influenza in different age group per 1000 high risk children Age group Under 1 year 1 to < 3 years 3 to < 15 years Excess hospitalisation per 1000 19 8 2 •Influenza morbidity is high in this class of patient, and often underestimated Neuzil KM et al. J Pediatr 2000; 137: 856–64. Other yearly consequences of influenza • Outpatients visits – 120 to 200 per 1000 atrisk children • Antibiotic courses – 65 to 140 per 1000 atrisk children Influenza in pregnancy Vulnerability during the second and third trimester Possible consequences: • • • Severe pulmonary complications and death for pregnant woman Foetal loss and abortion Other risks – foetal complications (growth, weight, etc.) – brain damage – neural tube defects Anonymous. Lancet 1994; 343: 665; Lynberg MC et al. Am J Epidemiol 1994; 140: 244–55; Takei N et al. Eur Arch Psychiatry Clin Neurosci 1995; 245: 255–9; Wright P et al. Am J Psychiatry 1995; 152: 1714–20. Pneumonia and influenza associated death Associated cardiovascular and pulmonary disease 870 Associated cardiovascular disease and diabetes 481 Pulmonary disease 240 Cardiovascular disease 104 Healthy adults Barker WH et al. Arch Intern Med 1982; 142: 85–9. 2 By courtesy of APACI Asia-Pacific Advisory Committee on influenza www.apaci-flu.com