eMedicine Specialties > Pediatrics: General Medicine > Infectious Disease

Respiratory Syncytial Virus (RSV) Infection

Leonard R Krilov, MD, Chief of Pediatric Infectious Diseases, Vice Chair, Department of Pediatrics, Professor of Pediatrics, Winthrop University Hospital

Updated: Jul 27, 2009

Introduction

Background

Respiratory syncytial virus (RSV) infection, which manifests primarily as bronchiolitis and/or viral pneumonia,¹ is the leading cause of lower respiratory tract (LRT) infection in infants and young children. The clinical entity of bronchiolitis was described at least 100 years ago.

An electron micrograph of respiratory syncytial virus (RSV). RSV is the most common cause of bronchiolitis and pneumonia in children younger than 1 year. Image courtesy of CDC.

Peak incidence of occurrence of severe RSV disease is observed at age 2-8 months. Overall, 4-5 million children younger than 4 years acquire an RSV infection, and more than 125,000 children are hospitalized annually in the United States because of this infection. This translates to 3-9 per 1000 children younger than 1 year who are hospitalized annually for this condition. Virtually all children have had at least one RSV infection by their third birthday. The World Health Organization has targeted RSV for vaccine development, which is not surprising, given the prevalence and potential severity of this condition.

This article reviews aspects of the virology, epidemiology, spectrum of clinical illness, diagnosis, treatment, and prevention of RSV-related illness.

Pathophysiology

RSV infection is limited to the respiratory tract. Initial infection in young infants or children frequently involves the LRT and most often manifests as the clinical entity of bronchiolitis. This clinical syndrome has been recognized for at least 100 years. Inoculation of the virus occurs in the URT in respiratory epithelial cells. Spread of the virus down the respiratory tract occurs by cell-to-cell transfer of the virus along intracytoplasmic bridges (syncytia) from the URT to the LRT.

The illness may begin with URT symptoms and progress rapidly over 1-2 days to the development of diffuse small airway disease characterized by cough, coryza, wheezing and rales, low-grade fever (<101°F), and decreased oral intake. A family history of asthma and/or atopy is frequently obtained.^2,3 In more advanced disease, retractions and cyanosis may be noted, and as many as 20% of patients may develop higher temperatures. The incidence of concomitant or secondary serious bacterial infection in association with RSV infection appears to be quite low (<1%), except for otitis media, which may occur in as many as 40% of cases. In very young infants, apnea out of proportion to respiratory signs and symptoms may be present, and, in infants younger than 6 weeks, a more nonspecific sepsislike picture has been described.⁴

Reinfection with RSV occurs at all ages; however, with recurrent infection and increasing age, RSV infections are more limited to the URT. RSV URT infection is more severe than the common cold, as evidenced by the 7-day to 10-day duration of illness and by the finding in one study of adults with RSV that the mean absence from work is 6 days. Data have also demonstrated severe RSV disease in the elderly.⁵

Frequency

United States

RSV LRT infection develops annually in 4-5 million children, and more than 125,000 children are admitted per year for RSV-related illness. Reinfection occurs throughout life, with the disease limited to the URT in persons older than 3 years. Severe RSV disease has been reported in older children and adults with severe underlying immunodeficiency disorders (eg, bone marrow transplantation), and RSV LRT disease has been reported in elderly persons.

Respiratory syncytial virus infection season, United States, by region and Florida. Image courtesy of CDC.

International

RSV infection is prevalent worldwide, with similar clinical manifestations and young age of RSV LRT infection.

Mortality/Morbidity

Even in children hospitalized with RSV infection, the mortality rate is less than 1%, with less than 500 deaths per year attributed to RSV in the United States. However, in select groups of high-risk patients, appreciable mortality and increased morbidity still may occur from this infection.^6,7,8

Infants with chronic lung disease of infancy (ie, bronchopulmonary dysplasia), congenital heart disease, or marked prematurity when hospitalized for this disease still may have a 3-5% mortality rate. Additionally, such infants and patients with immunodeficient states have been shown to spend, on average, twice as long in the hospital as other patients with RSV infection (7-8 d vs 3-4 d in normal full-term infants).

Additionally, children hospitalized for RSV disease during infancy have been shown to have abnormal pulmonary function test results and/or increased episodes of wheezing as long as 10 years later. Whether RSV itself plays an active role in this or is just a marker for children at risk for reactive airway disease remains controversial.

Race

All races appear susceptible to RSV, with similar disease patterns.

Sex

Although boys and girls are equally affected by milder RSV disease, the frequency of hospitalization for RSV disease is higher in males, with a male-female-ratio of approximately 2:1.

Age

Severe RSV disease is primarily a disease of young infants and children, with a peak occurrence at age 2-8 months. Reinfection with RSV occurs throughout life, with disease becoming more limited to the URT, as discussed above.

Clinical

History

Patients with respiratory syncytial virus (RSV) infection may present with the following symptoms:

• Fever (typically low-grade)
• Cough
• Tachypnea
• Cyanosis
• Retractions
• Wheezing
• Rales
• Sepsislike presentation or apneic episodes (in very young infants)

Physical

• Physical examination of the infant with RSV lower respiratory tract (LRT) infection reveals evidence of diffuse small airway disease.
• As many as 40% of children have an associated otitis media, which may be viral and/or bacterial.
• Additionally, assessment of the infant's hydration status (eg, skin turgor, capillary refill, mucous membranes) is an important part of the physical examination of the infant with bronchiolitis.

Causes

• In the community setting, a number of factors have been associated with increased risk of acquiring RSV disease, including the following:
  • Childcare attendance
  • Older siblings in preschool or school
  • Crowding, lower socioeconomic status
  • Exposure to environmental pollutants (eg, cigarette smoke)
  • Multiple birth sets (especially triplets or greater)
  • Minimal breastfeeding
• In assessing an infant with RSV infection, several factors have been correlated with more severe disease and the need for hospitalization. Although infants in these groups (outlined below) are at increased risk for severe RSV disease compared to normal full-term infants based on percentage, many more children in the normal full-term group are admitted; thus, most admissions for RSV disease occur in otherwise normal infants. Family history of asthma and genetic factors also correlate with more severe RSV disease, although the exact relationship and mechanisms have not been elucidated.
  • Prematurity, especially birth at less than 35 weeks' gestation⁹
  • Age younger than 3 months at time of infection
  • Chronic lung disease
  • Congenital heart disease
  • Congenital immunodeficiency (eg, severe combined immunodeficiency [SCID])
  • Severe neuromuscular disease
  • Toxic appearance at time of presentation
  • Respiratory rate more than 70 per minute in room air
  • Atelectasis and/or pneumonitis on chest radiography
  • Oxygen less than 95% on room air

Differential Diagnoses

Other Problems to Be Considered

Reactive airway disease

Workup

Laboratory Studies

• Laboratory studies frequently are not indicated in the infant with bronchiolitis who is comfortable in room air, well hydrated, and feeding adequately.
• Nonspecific laboratory studies may include CBC count, serum electrolytes, urinalysis, and oxygen saturation measurement. The CBC count may reveal a normal or mildly elevated WBC count and an elevated percentage of band forms. Blood cultures, although obtained frequently, are rarely positive for pathogenic bacteria.
• An arterial blood gas may be indicated if carbon dioxide retention is a concern.
• Specific diagnostic tests for confirmation of respiratory syncytial virus (RSV) infection are readily available. These tests can be performed on samples of secretions obtained by washing, suctioning, or swabbing the nasopharynx. Secretions can be analyzed for virus in the laboratory by culture and/or antigen revealing techniques. Newer molecular probes for revealing RSV in clinical specimens are being developed and may be more sensitive than the above assays, although they are not routinely available at this time.
• The antigen detection methods offer the potential for diagnosis within hours and may be obtained reliably in the absence of a sophisticated virology laboratory. However, monitoring of test performance is critical in maintaining appropriate sensitivity and specificity. Specific tests for RSV may be indicated for making decisions regarding therapy (eg, withdrawal of unnecessary antibiotics), isolation of patients, and in educating parents and staff about the nature of RSV disease.

Imaging Studies

• Chest radiography is frequently obtained in children with severe RSV infection.
• Chest radiography typically reveals hyperinflated lung fields with a diffuse increase in interstitial markings.
• In 20-25% of cases, focal areas of atelectasis and/or pulmonary infiltrate are also noted.
• Generally, these findings are neither specific to RSV infection nor predictive of the course or outcome, except for the observation that infants who have the additional findings of atelectasis and/or pneumonia may have a more severe course with their illness.

Histologic Findings

• In infants who have died from RSV bronchiolitis, lung tissue demonstrates mononuclear cell and neutrophil infiltration of the peribronchiolar areas, necrosis of the small airway epithelium, plugging of the lumens with exudate and edema, and atelectasis and hyperinflation.

Treatment

Medical Care

• Supportive care is the mainstay of therapy for respiratory syncytial virus (RSV) infection. If the child can take in fluids by mouth and tolerate room air, outpatient management, with close physician contact as needed, is reasonable, especially in the absence of significant underlying risk factors. Although bronchodilators have been used, no convincing data as to their efficacy in this setting exist.
• For children who require hospitalization for RSV infection, supportive therapy is still the mainstay of care. Supportive care may include administration of supplemental oxygen (guided by respiratory rates, work of breathing, oxygen saturation, and arterial blood gases, as indicated), mechanical ventilation, and fluid replacement, as necessary. Additionally, bronchodilator therapy with beta-agonists frequently is used, although data on their benefit in this condition are conflicting. At least a subset of patients with RSV-related lower respiratory tract (LRT) infection appears to benefit from such therapy, and a trial with monitoring for effect on respiratory rate, pulse, and oxygenation may be reasonable. Alpha agonists (eg, vaporized epinephrine) have also been used during acute bronchiolitis episodes, although, again, available data do not clearly demonstrate efficacy.
• In 1986, the US Food and Drug Administration (FDA) licensed ribavirin, a broad-spectrum antiviral agent in vitro, for the aerosolized treatment of children with severe RSV disease. The recommended dose is 6 g of drug in 300 mL of distilled water via a small-particle aerosol generator (SPAG unit) over 12-20 hours per day for 3-7 days based on clinical response. Subsequent studies have suggested equivalent efficacy with a higher concentration of drug (6 g/100 mL distilled water) given over three 2-hour periods per day. The use of ribavirin has been limited because of its high acquisition cost and lack of demonstrated benefit in decreasing hospitalization or mortality.
• Secondary toxicity to health care workers from exposure to aerosolized drug was a theoretical concern in the past, although such risk is unproved. For these reasons, ribavirin primarily is reserved for patients with significant underlying risk factors and severe acute RSV disease. Several reports suggest that older children and adults with symptomatic RSV infection after bone marrow transplantation may benefit from ribavirin therapy. If preliminary studies suggesting a long-term benefit (see Complications) are confirmed, broader indications for ribavirin therapy may become a consideration.

Consultations

The primary caretaker, on an outpatient basis, manages most cases of RSV. Even in the hospitalized child with RSV disease, consultation with a subspecialist generally is not necessary.

• Pediatric intensivist: Consultation with an intensivist is advised if the child requires mechanical ventilation or, even before intubation, if the child has marked respiratory distress and a high supplemental oxygen requirement. An intensivist may also be of assistance if difficult issues in fluid management (eg, congenital heart disease, bronchopulmonary dysplasia) occur in which assessment of hydration status and optimal fluid management may be complex.
• Pediatric infectious disease specialist: An infectious diseases evaluation may be indicated if ribavirin therapy is being considered or if the viral origin of the infant's acute respiratory illness is uncertain. Infectious disease specialists often also play a role in addressing epidemiological concerns regarding patient isolation, nosocomial transmission,¹⁰ and infection control.
• Pediatric pulmonologist: A pediatric pulmonologist may be consulted if the infant has underlying lung disease (eg, bronchopulmonary dysplasia)¹¹ in conjunction with the acute RSV infection or to assist in decisions regarding bronchodilator therapy.

Diet

• Most infants who are hospitalized with RSV infection are unable to tolerate milk or feedings well and frequently vomit or spit up.
• A brief course of intravenous fluids is generally administered in this setting, with resumption of normal feeding as the child recovers typically over 2-3 days.

Medication

Medications to treat respiratory syncytial virus (RSV) include the antiviral drug ribavirin, which can be used in severe high-risk cases and bronchodilators. Efficacy of bronchodilators or racemic epinephrine in treating RSV disease still has not been proven. If these agents are given, attempts to measure response to therapy should be documented. If benefit to these treatments is not demonstrated, they should be discontinued. Although corticosteroids are administered at times to patients with this condition, clinical data do not support the use of corticosteroids in the treatment of typical RSV bronchiolitis.

Antiviral agents

Antiviral therapy for severe RSV disease is indicated in high-risk patients. Treatment must be promptly initiated at the onset of the infection to effectively inhibit the replicating virus.

Ribavirin (Virazole)

Analog of the nucleic acid guanosine. Ribavirin inhibits viral replication by an unknown mechanism.

Dosing

Adult

Reconstitute 6 g in 300 mL of distilled water to a concentration of 20 mg/mL
Administer as aerosol for 12-20 h/d for 3-7 d based on clinical response
Alternatively, 6 g in 100 mL of distilled water aerosol in 2-h pulses tid has been suggested as equally effective in small studies

Pediatric

Administer as in adults

Interactions

Decreases zidovudine effect when administered concurrently

Contraindications

Documented hypersensitivity; pregnancy; women who may become pregnant during drug course

Precautions

Pregnancy

X - Contraindicated; benefit does not outweigh risk

Precautions

Caution with mechanical ventilation; pay strict attention to minimization of drug precipitation, which may interfere with ventilator function and cause increased pulmonary pressures; affected parts include heated wire tubing, filters in the expiratory limb of the ventilator circuit, and water column pressure release valves
Ribavirin has demonstrated teratogenic effects in rodents and rabbits; the amount of drug that one would be exposed to in caring for a child receiving aerosolized ribavirin is likely to be minimal, and teratogenesis has not been reported in offspring of mothers exposed to aerosolized ribavirin during pregnancy; however, avoiding unnecessary exposure to the drug is advisable (this can be accomplished by turning off the SPAG unit administering the drug for 5-10 min before prolonged patient contact, use of a ribavirin scavenger device, and administration in a room with adequate ventilation)

Bronchodilators

These act to decrease muscle tone in the small and large airways in the lungs, thereby increasing ventilation. Beta2-adrenergic and alpha-adrenergic agents frequently are used (via inhalation) in an attempt to treat the bronchospasm observed in bronchiolitis.

Albuterol (AccuNeb, Proventil)

As a selective beta2-agonist, this agent produces bronchial smooth muscle relaxation. Efficacy in older children with reactive airway disease is well established, but the benefits in acute bronchiolitis are less well established. Available in inhalation and PO preparations.

Dosing

Adult

Not applicable in adults

Pediatric

Acute bronchiolitis: 0.01-0.05 mL/kg inhaled (via nebulization of 5 mg/mL of solution) q4-6h
Outpatient: 2-4 mg/dose PO (syrup) tid/qid sometimes is used in young children

Interactions

Beta-blockers may block pulmonary effects and induce severe bronchospasm; possible potentiation of effects on vascular system with concomitant MAOIs and tricyclic antidepressants; possible decreased digoxin levels; possible worsening of hypokalemia if coadministered with non–potassium-sparing diuretics

Contraindications

Documented hypersensitivity

Precautions

Pregnancy

C - Fetal risk revealed in studies in animals but not established or not studied in humans; may use if benefits outweigh risk to fetus

Precautions

Caution in hyperthyroidism, diabetes mellitus, and cardiovascular disorders

Racemic epinephrine (microNefrin, Nephron, S-2)

This drug is 1-1.125% of epinephrine base solution given by aerosol. Recent studies suggest it may be superior to beta2-agonists in RSV LRTI.

Dosing

Adult

Not applicable in adults

Pediatric

Bronchiolitis: 0.1 mL/kg/dose (diluted with 0.9% NaCl to final volume of 3 mL) inhaled via nebulizer q3-4h

Interactions

Coadministration with of beta-blocking and alpha-blocking agents may result in hypertension; coadministration with halogenated inhalational anesthetics may result in ventricular arrhythmias

Contraindications

Documented hypersensitivity; cardiac arrhythmias; angle-closure glaucoma

Precautions

Pregnancy

C - Fetal risk revealed in studies in animals but not established or not studied in humans; may use if benefits outweigh risk to fetus

Precautions

Monitor for tachycardia and hypertension

Antiviral immunoglobulins

Specific immunoglobulin products with anti-RSV activity have been developed for the prophylaxis of high-risk patients against RSV infection.

Palivizumab (Synagis)

A humanized monoclonal antibody directed against the F (fusion) protein of RSV. Administered monthly through the RSV season, it has been demonstrated to decrease the chances of RSV hospitalization in premature babies who are at increased risk for severe RSV-related illness.

Dosing

Adult

Not applicable; not approved for adults

Pediatric

15 mg/kg/dose IM every mo through RSV season (typically November through April in the northern hemisphere)

Interactions

None reported

Contraindications

Documented hypersensitivity

Precautions

Pregnancy

C - Fetal risk revealed in studies in animals but not established or not studied in humans; may use if benefits outweigh risk to fetus

Precautions

Thrombocytopenia or coagulation disorder, as with any IM injection

Follow-up

Deterrence/Prevention

• Respiratory syncytial virus (RSV) transmission appears to occur via contact with infected secretions through hand-to-hand spread and/or fomites and respiratory droplets with an incubation period of 3-5 days.¹² Aerosolized secretions appear to be less important in RSV transmission; thus, attention to handwashing and cleaning of environmental surfaces are important to prevent RSV transmission. In the hospital setting, isolation of patients infected with RSV as a group and wearing of mask and gown during close contact with infected children are important in controlling nosocomial spread. Transmission of RSV on pediatric units has been shown to be a significant problem.
• Despite good environmental hygiene, RSV infection is likely to occur with significant frequency.
• Immunoglobulin products with high anti-RSV antibody titers have proved beneficial when given monthly for prophylaxis in select groups of high-risk infants. Presently, this is accomplished with monthly administration of palivizumab (Synagis), a humanized monoclonal antibody.¹³
  • RSV-intravenous immunoglobulin (IVIG) is a pooled polyclonal human immunoglobulin product prepared from donors with high titers of RSV antibodies. When administered to high-risk infants with prematurity and/or chronic lung disease, a significant decrease in RSV-related hospitalization was noted. Additionally, treated infants had less severe hospital courses if admitted with RSV disease, fewer other respiratory infection hospitalizations, and fewer cases of otitis media than placebo recipients. This product requires intravenous administration at a dose of 750 mg/kg monthly during RSV season (typically, November through May or April in temperate climates). Given the need for monthly intravenous infusion and fluid volume load, the number of children who can be protected in this manner was limited, and, with the licensure of palivizumab (Synagis), this agent is no longer being manufactured.
  • Presently, passive protection against RSV is achieved successfully through monthly intramuscular injection of the humanized monoclonal anti-RSV antibody palivizumab (Synagis; MedImmune; Gaithersburg, Md) at a dose of 15 mg/kg IM per month.
    • This product demonstrated a 55% reduction in RSV hospitalization in premature infants born at less than 35 weeks' gestation who were younger than 6 months chronological age and in infants who had bronchopulmonary dysplasia and were younger than 24 months chronological age;¹⁴ This reduction led to FDA approval in 1998.
    • A separate study in infants younger than 2 years who had hemodynamically significant congenital heart disease also demonstrated safety and efficacy of palivizumab prophylaxis in this high-risk population.  Subsequent postmarketing studies have continued to demonstrate efficacy. In November 2005, a stable liquid preparation of the drug became available, replacing the lyophilized form used previously. The dosing and concentration of the liquid preparation have not changed
    • Immunoglobulin products are expensive to administer (approximately $5,000-6,000 per child per year), leading to debate regarding which children should receive such prophylaxis
    • Palivizumab (Synagis) is approved for prophylaxis of children at high risk for severe RSV disease. Clinical trials have demonstrated efficacy and safety in premature infants younger than 6 months and those with chronic lung disease of infancy and congenital heart disease younger than 2 years at the start of the RSV season. Infants with immunodeficiency or severe neuromuscular disease have not been studied in conjunction with these products because of limitations in the numbers of such patients
    • The American Academy of Pediatrics (AAP) guidelines for RSV prophylaxis (see below) attempt to address these issues by grading the indications for preventive therapy by degree of prematurity and/or risk factor.¹⁵ Pending further follow-up and economic impact studies, the AAP recommendations, last revised in 2006, provide a rational approach to selecting candidates for RSV prophylaxis.
• The AAP Committee on Infectious Diseases guidelines for candidates for palivizumab (Synagis) prophylaxis are as follows:¹⁵
  • Infants younger than 24 months who have hemodynamically significant congenital heart disease (cyanotic or acyanotic lesions) or chronic lung disease and are off oxygen and/or pulmonary medications for less than 6 months at the start of RSV season
  • Premature infants born at less than 28 weeks' gestational age who are younger than 1 year chronological age at the start of RSV season
  • Premature infants born at 29-32 weeks' gestational age who are younger than 6 months chronological age at the start of RSV season
  • Infants born at 33-35 weeks' gestational age who are younger than 6 months chronological age and have at least 2 additional risk factors at the start of RSV season¹⁶
• The AAP guidelines highlight child care attendance, school-aged siblings, exposure to environmental pollutants, congenital anomalies of the airway, and severe neuromuscular disorders as the primary additional risk factors for these patients.
• Attempts to develop a vaccine against RSV (as opposed to the passive protection discussed above) have been unsuccessful to date.¹⁷ A formalin-inactivated RSV vaccine was developed in the 1960s. Although initial serological responses to this vaccine appeared promising, children who received this vaccine developed more severe disease, with a number of deaths, when exposed to natural RSV infection. The development of a successful RSV vaccine must address this issue and achieve protection of very young children if it is to have an impact on severe RSV disease. Recent progress in this area has included development of stable, live-attenuated RSV vaccines that can be administered as nasal spray. Despite progress in this area, a vaccine that is ready for use in clinical practice is still likely 5-10 years away.
• A second-generation monoclonal antibody, motavizumab, has increased affinity for RSV compared with palivizumab and is currently under investigation. Preliminary data compared palivizumab with motavizumab in a premature population suggested noninferiority for motavizumab in preventing hospitalization and superiority to palivizumab for protection against medically attended lower respiratory infection. Motavizumab is not currently FDA approved or available for clinical use.¹⁸
• Another approach is the development of an RSV vaccine that involves use of cloned RSV surface proteins as potential subunit vaccines. RSV fusion (F) and glycoprotein (G) can induce neutralizing and protective antibodies and are the components in development. These are being evaluated for potential immunization of young children and also for administration to pregnant women during the last trimester to boost anti-RSV antibody levels transferred to the infant.

Complications

• Infants hospitalized for RSV lower respiratory tract (LRT) infection in infancy have a higher risk for subsequent wheezing and abnormal pulmonary function tests as long as 10 years later than age-matched control subjects who did not have such an admission. RSV's role in causing subsequent reactive airway disease remains controversial. Several small studies have suggested that infants who are hospitalized with RSV infection and treated with ribavirin have better pulmonary function on follow-up than children who do not receive such therapy. If this finding is confirmed, it offers better understanding of the link between RSV LRT in infancy and subsequent reactive airway disease. Similarly, analyses of recipients of RSV prophylaxis compared with control subjects may help answer this clinically important question.
• A small retrospective study in Europe and Canada suggested that premature infants who received palivizumab prophylaxis had less subsequent respiratory illness visits over a 2-year period than infants matched for gestational and chronological age who did not receive prophylaxis.

Prognosis

• Children hospitalized secondary to RSV infection typically recover and are discharged in 3-4 days. High-risk infants remain hospitalized longer and have higher rates of ICU admission and mechanical ventilation. 
• Infants hospitalized due to RSV infection have higher rates of subsequent wheezing than age-matched controls not hospitalized for this condition over the next 10 or more years. Whether RSV leads to alterations of airways and/or immune responses that contribute to these subsequent events or is just a marker for abnormal airways is still not completely understood. 

Patient Education

• For excellent patient education resources, visit eMedicine's Pneumonia Center and Cold and Flu Center. Also, see eMedicine's patient education articles Viral Pneumonia and Flu in Children.

Miscellaneous

Medicolegal Pitfalls

• The primary medical/legal pitfall relating to respiratory syncytial virus (RSV) disease is failure to recognize the severity of lung disease and degree of hypoxemia in a particular child. Careful history, physical examination, and, if indicated, oxygen saturation measurement should be adequate for revealing severe illness children.
• The author is not aware of any related legal issues to date, but it has been suggested that failure to offer prophylactic therapy (eg, palivizumab) to a high-risk neonate who subsequently develops severe RSV disease might pose a medicolegal concern. Numerous law suits for high-risk infants who have acquired nosocomial RSV infection have been filed.

Special Concerns

• High-risk groups for severe RSV infection include the following:
  • Premature infants in their first year of life (the younger the child is [gestational and chronological age] at the start of RSV season, the greater the risk)
  • Infants with chronic lung disease (eg, bronchopulmonary dysplasia, cystic fibrosis) during their first 2 years of life
  • Children with hemodynamically significant congenital heart disease, especially with increased pulmonary blood flow
  • Immunodeficient states
  • Children with metabolic and neuromuscular disorders
  • Children of multiple births (triplets or greater)

Multimedia

Media file 1: Respiratory syncytial virus infection season, United States, by region and Florida. Image courtesy of CDC.

Media file 2: An electron micrograph of respiratory syncytial virus (RSV). RSV is the most common cause of bronchiolitis and pneumonia in children younger than 1 year. Image courtesy of CDC.

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Keywords

respiratory syncytial virus infection, RSV, bronchiolitis, viral pneumonia, lower respiratory tract infection, LRT infection, upper respiratory tract infection, URT infection, chimpanzee coryza agent, Rs virus, asthma, otitis media, bone marrow transplantation, chronic lung disease of infancy, bronchopulmonary dysplasia, congenital heart disease, reactive airway disease, prematurity, severe combined immunodeficiency, SCID, atelectasis, pneumonitis, treatment, diagnosis

Contributor Information and Disclosures

Author

Leonard R Krilov, MD, Chief of Pediatric Infectious Diseases, Vice Chair, Department of Pediatrics, Professor of Pediatrics, Winthrop University Hospital
Leonard R Krilov, MD is a member of the following medical societies: American Academy of Pediatrics, American Pediatric Society, Infectious Diseases Society of America, Pediatric Infectious Diseases Society, and Society for Pediatric Research
Disclosure: Medimmune Grant/research funds Cliinical trials; Medimmune Honoraria Speaking and teaching; Medimmune Consulting fee Consulting

Medical Editor

Ashir Kumar, MBBS, MD, FAAP, Professor, Department of Pediatrics and Human Development, College of Human Medicine, Michigan State University; Consulting Staff, Department of Pediatrics, EW Sparrow Hospital
Ashir Kumar, MBBS, MD, FAAP is a member of the following medical societies: American Academy of Pediatrics, American Association of Physicians of Indian Origin, American Federation for Clinical Research, American Society for Microbiology, Infectious Diseases Society of America, and Pediatric Infectious Diseases Society
Disclosure: Nothing to disclose.

Pharmacy Editor

Mary L Windle, PharmD, Adjunct Assistant Professor, University of Nebraska Medical Center College of Pharmacy, Pharmacy Editor, eMedicine
Disclosure: Pfizer Inc Stock Investment from financial planner; Avanir Pharma Stock Investment from financial planner ; WebMD Salary and stock Employment and investment from financial planner

Managing Editor

Larry I Lutwick, MD, Professor of Medicine, State University of New York, Downstate Medical School; Director, Infectious Diseases, Veterans Affairs New York Harbor Health Care System, Brooklyn Campus
Larry I Lutwick, MD is a member of the following medical societies: American College of Physicians and Infectious Diseases Society of America
Disclosure: Nothing to disclose.

CME Editor

Robert W Tolan Jr, MD, Chief, Division of Allergy, Immunology and Infectious Diseases, The Children's Hospital at Saint Peter's University Hospital; Clinical Associate Professor of Pediatrics, Drexel University College of Medicine
Robert W Tolan Jr, MD is a member of the following medical societies: American Academy of Pediatrics, American Medical Association, American Society for Microbiology, American Society of Tropical Medicine and Hygiene, Infectious Diseases Society of America, Pediatric Infectious Diseases Society, Phi Beta Kappa, and Physicians for Social Responsibility
Disclosure: GlaxoSmithKline Honoraria Speaking and teaching; MedImmune Honoraria Speaking and teaching; Merck Honoraria Speaking and teaching; sanofi pasteur Honoraria Speaking and teaching; Baxter Healthcare Honoraria Speaking and teaching

Chief Editor

Russell W Steele, MD, Head, Division of Pediatric Infectious Diseases, Ochsner Children's Health Center; Clinical Professor, Department of Pediatrics, Tulane University School of Medicine
Russell W Steele, MD is a member of the following medical societies: American Academy of Pediatrics, American Association of Immunologists, American Pediatric Society, American Society for Microbiology, Infectious Diseases Society of America, Louisiana State Medical Society, Pediatric Infectious Diseases Society, Society for Pediatric Research, and Southern Medical Association
Disclosure: None None None

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