Respiratory syncytial virus (RSV) infection

Description of Medical Condition

RSV causes respiratory illness

• Adults: URI’s
• Infants and children: bronchitis, bronchiolitis, pneumonia
• Leading cause of pediatric admissions for respiratory illness

System(s) affected: Pulmonary

Genetics: None known

Incidence/Prevalence in USA: Common in winter. Almost all persons infected one or more times during lifetime.

Predominant age: Birth to age 2

Predominant sex:

• Males = females as outpatients
• 2:1 males/females in hospital

Medical Symptoms and Signs of Disease

Cold signs and symptoms (mild disease)

• Fever
• Cough
• Coryza
• Congestion
• Otitis media
• Malaise

Bronchitis/bronchiolitis/pneumonia

• Cough
• Chest congestion, rales/rhonchi
• Wheezing
• Dyspnea
• Hypoxia
• Cyanosis

Vomiting

What Causes Disease?

Infection with RSV

Risk Factors

• Impaired immunity OAIDS
  • Chemotherapy
  • Other types of impaired immunity
• Occupational exposure
  • Day care workers
  • Pediatric hospital staff
  • School teachers
• Neonatal/congenital conditions
  • Congenital cardiac anomalies
  • Respiratory distress syndrome
  • Premature birth
• Low socioeconomic status
• More common in urban vs. rural areas

Diagnosis of Disease

Differential Diagnosis

• Mild illness/upper respiratory tract
  • Colds (non RSV)
  • Allergic rhinitis
  • Sinusitis
  • Croup
• Severe illness/lower respiratory tract
  • Asthma
  • Bronchitis
  • Bronchiolitis
  • Pneumonia

Laboratory

• WBC may be normal to elevated
• Positive RSV antigen test on nasal washings

Drugs that may alter lab results: None

Disorders that may alter lab results: None

Pathological Findings

Lymphocytic peribronchiolar infiltrates (autopsy)

Imaging

Chest x-ray

• Hyperinflation — most common, characteristic finding
• Interstitial infiltrates — fairly common
• Segmental or lobar consolidation in pneumonia
• Pleural fluid

Diagnostic Procedures

None

Treatment (Medical Therapy)

Appropriate Health Care

Outpatient for mild cases; inpatient for severe disease or for those with underlying disorders. Illness can last from days to several weeks.

General Measures

Outpatient

• Rest/supportive care
• Bronchodilators — albuterol nebulizer/inhaler
• Monitor oxygenation-pulse oximeter

Inpatient

• Oxygen
• Bronchodilators — albuterol nebulizer q4h
• Respiratory isolation ORibavirin
• Antibiotics for secondary bacterial pneumonia
• Monitor arterial blood gases/pulse oximeter
• Use of steroids is controversial; may help in some cases

Avoid exposing others

• Remove from day care/school until well
• Good hand washing practices
• Respiratory isolation in hospital

Activity

Decreased household activity/rest

Diet

• Maintain nutrition
• Avoid over-hydration (may increase lung congestion)

Medications (Drugs, Medicines)

Drug(s) of Choice

• Ribavirin 20 mg/mL mist 12-18 hours/day for 3-7 days. (Can shorten duration and severity of illness.)
• Bronchodilators — albuterol nebulizer q4h (dose appropriate for age)
• Antibiotics for secondary bacterial infections/pneumonia
  • Appropriate to particular pathogen
  • Prophylactic use of antibiotics controversial
• Potential use of RSV immune globulin in high risk infants

Contraindications: See specific drug related information

Precautions: Avoid exposure of pregnant/potentially pregnant women to ribavirin

Significant possible interactions: See specific drug information

Alternative Drugs

• Antibiotic appropriate to identified or suspected bacterial pathogen
• Theophylline use all right, but not recommended

Patient Monitoring

• Uneventful resolution is the norm
• No special monitoring is needed as illness resolves
• May want to educate parents about SIDS — avoid prone sleeping in infants

Prevention / Avoidance

• Avoid exposure to those ill with RSV
• Good hand washing practices (since hand-nose and hand-eye transmission is common)
• Avoid rubbing the eyes (common RSV inoculation route)
• Use of palivizumab (Synagis) recommended for pree-mies < 35 weeks and infants with bronchopulmonary dysplasia prior to and during RSV season (Fall, Winter, Spring). Dose 15 mg/kg of body weight IM monthly.

Possible Complications

• Pneumonia
• Sudden infant death
• Death from severe lower respiratory tract infections
• Possible residual lung damage

Expected Course / Prognosis

• Usually resolves within two weeks without sequelae
• Hospitalization rate of children ill with RSV varies from 1:50 to 1:200 (children < 2 years old)

Miscellaneous

Associated Conditions

• Asthma is worse with RSV and vice versa
• SIDS may be a sequelae of RSV

Age-Related Factors

Pediatric: Most common under age 2

Geriatric: N/A

Others: Increasing immunity with subsequent infections by RSV usually results in less serious illness

Pregnancy

• Avoid ribavirin therapy in pregnancy
• Healthcare workers who may be pregnant should avoid exposure to ribavirin

International Classification of Diseases

480.1 Pneumonia due to respiratory syncytial virus

See Also

Bronchiolitis Pneumonia, bacterial Pneumonia, viral Bronchitis, acute

Abbreviations

• RSV = respiratory syncytial virus
• SIDS = sudden infant death syndrome
• URI = upper respiratory infection