INFLUENZA COMPLICATIONS

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INFLUENZA COMPLICATIONS
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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 2637.
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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

510 of pneumonia is an influenza complication
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Influenza complications

• Primary viral pneumonia
• Bacterial secondary pneumonia
• Tracheobronchitis
• Bronchiolitis
• Congestive heart failure
• Myocarditis, pericarditis
• Complications of sinus, middle ear, musculature
• Reyes 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

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Groups at higher risk of complications

• Elderly (gt 60 years of age), especially in
  residential care units
• Children and teenagers (6 months18 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 11738.
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Age distribution of respiratory complications
80
60
Respiratory complications ()
40
20
0
04
59
1019
2039
4049
5059
5069
gt 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 130625.
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Influenza complicationsin 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 2637.
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Severe symptoms in children
Kilbourne ED. Influenza. New York Plenum Medical
Book Company 1987 15766.
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Influenza in children with asthma and other
chronic medical conditions

• Retrospective cohort study, Tennessee Medicaid
  program (19731993)
• 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
Other yearly consequencesof influenza

• Outpatients visits
• 120 to 200 per 1000 at-risk children
• Antibiotic courses
• 65 to 140 per 1000 at-risk children

Age group
Excess hospitalisation
per 1000
Under 1 year
19
1 to lt 3 years
8
3 to lt 15 years
2

• Influenza morbidity is high in this class of
  patient,and often underestimated

Neuzil KM et al. J Pediatr 2000 137 85664.
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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 24455 Takei N et
al. Eur Arch Psychiatry Clin Neurosci 1995 245
2559 Wright P et al. Am J Psychiatry 1995 152
171420.
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Pneumonia and influenza associated death
Barker WH et al. Arch Intern Med 1982 142 859.
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By courtesy of APACIAsia-Pacific Advisory
Committee on influenzawww.apaci-flu.com