Respiratory syncytial virus infection

Last reviewed: 7 Jan 2023
Last updated: 24 Nov 2022



History and exam

Key diagnostic factors

  • presence of risk factors
  • exposure to RSV
  • infants at high risk for RSV infection
  • older adult age
  • winter season
  • immune deficit
  • rhinorrhoea/congestion
  • tachypnoea
  • increased work of breathing
  • cough
  • wheeze
  • poor feeding
  • cyanosis
  • rales
  • apnoea
More key diagnostic factors

Other diagnostic factors

  • fever
Other diagnostic factors

Risk factors

  • exposure to RSV
  • haemodynamically significant congenital heart disease
  • history of prematurity
  • immune deficit
  • chronic lung disease
  • high-risk infants with no recent immunoprophylaxis against RSV
  • infants aged <6 months
  • winter season
  • older adult age
  • smoke exposure
  • family history of asthma
  • Down's syndrome
More risk factors

Diagnostic investigations

1st investigations to order

  • pulse oximetry
More 1st investigations to order

Investigations to consider

  • chest x-ray
  • hydration status
  • direct fluorescent antibody staining of respiratory specimen (e.g., nasopharyngeal aspirate)
  • reverse transcriptase polymerase chain reaction of respiratory specimen (e.g., nasopharyngeal aspirate)
  • viral culture of respiratory specimen (e.g., nasopharyngeal aspirate)
More investigations to consider

Treatment algorithm


mild or self-limiting illness

moderate illness

severe illness



Giovanni Piedimonte, MD, FAAP, FCCP

Vice President for Research

Professor of Pediatrics, Biochemistry & Molecular Biology

Tulane University School of Medicine

New Orleans



GP declares that he has no competing interests.

Margot Anderson, MD

Assistant Professor of Clinical Pediatrics

Section of Infectious Diseases and Hospital Medicine

Tulane University School of Medicine

Tulane University

New Orleans



MA will be the principle investigator for a phase 3 trial to ealuate the safety, efficacy, and pharmacokinetics of MK-1654 in infants and children at increased risk for severe respiratory syncytial virus disease, based at Tulane University School of Medicine. Merck will reimburse Tulane University for participation.


Dr Giovanni Piedimonte and Dr Margot Anderson would like to gratefully acknowledge Dr Frank Esper and Dr Melvin L. Wright, previous contributors to this topic.


FE is on an advisory board for Procter and Gamble. MLW declares that he has no competing interests.

Peer reviewers

Leonard R. Krilov, MD


Pediatric Infectious Disease

Vice Chairman

Department of Pediatrics

Children's Medical Center

Winthrop University Medical Center


Professor of Pediatrics

School of Medicine

Stony Brook University Medical Center

Stony Brook



LRK has participated as an investigator in multiple clinical research trials supported by grants from MedImmune. LRK has also served as a consultant to MedImmune on medical advisory boards and is a member of their speakers' bureau.

Robert Welliver, MD

Professor of Pediatrics

Women and Children's Hospital




RW declares that he has no competing interests.

Jennifer Handforth, MB ChB, MRCPCH, DTM&H

Consultant Paediatrician

Croydon University Hospital




JH declares that she has no competing interests.

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