Respiratory syncytial virus: How, why and what to do
Section snippets
The virus
RSV is a member of the Mononegavirales in the Paramyxoviridae family, and Pneumovirinae subfamily. RSV is an enveloped virus with a negative sense, single-stranded RNA genome. These viruses are 150–200 nm in diameter with a helical nucleocapside. RSV has 10 genes encoding 11 proteins—there are 2 open reading frames of M2. The NS1 and NS2 proteins inhibit type I interferon activity. N protein encodes the nucleocapsid protein that associates with the genomic RNA forming the nucleocapsid, and the
Epidemiology and global burden of RSV
Acute lower respiratory infection (ALRI) is the leading cause of global child mortality. Respiratory syncytial virus (RSV) is the most frequent viral pathogen causing ALRI in young children. The global burden of RSV is significant.2, 3 A recent meta-analysis suggests that RSV causes up to 33.8 million ALRIs among children under age 5 (22% of all Lower Respiratory Tract Infections) each year. At least 3.4 million cases required hospital admission, and an estimated 66,000–199,000 of children
Vitamin D and bronchiolitis
Vitamin D status is determined largely from ultraviolet B ray exposure at all ages. Vitamin D also is available from dietary sources, which are more important at higher latitudes at which ultraviolet B ray exposure is inadequate for skin synthesis of vitamin D during winter. The diverse sources of vitamin D, which involve environmental conditions and complex behaviors, complicate vitamin D research. Fortunately, serum 25(OH)D levels provide an excellent measure of overall vitamin D status.
In a
Molecular diagnosis and co-infections
The development of sensitive molecular diagnostic assays has increased the number of viruses detected in respiratory samples compared with conventional methods. A number of studies have used PCR-based assays to study the etiology of bronchiolitis in hospitalized children. Using these methods several investigators have identified viruses in >90% cases of bronchiolitis. In hospitalized infants, RSV was the most frequent agent of bronchiolitis in winter, but other viruses were present in up to 47%
Viral load
The relationships between host factors, virus strain, viral load, and illness severity in respiratory syncytial virus (RSV)-induced bronchiolitis are still poorly defined. In this area studies offer contradictory results.17, 18, 19 Most studies that have attempted to associate viral load measured by quantitative real time PCR with disease severity have failed to establish any significant correlation.20, 21, 22, 23 However, two studies that measured viral load using quantitative cultures and
Etiologic diagnosis of bronchiolitis: is it relevant?
As the application of molecular diagnostic assays for respiratory viruses becomes more frequent both in research studies and academic medical centers, physicians raise questions concerning the value of such tests in clinical practice. One argument favoring their use, from the infection control perspective, is the importance, were feasible, of isolating patients according to etiology to prevent hospital-associated infections. In addition, a recent study conducted by Finnish investigators
Palivizumab and motavizumab
Palivizumab, a humanized monoclonal antibody directed against the F protein of RSV, has been used since 1998 in USA and 61 other countries for prevention of severe RSV infection in high-risk children.26 Motavizumab is a neutralizing antibody derived from palivizumab that showed greater neutralization activity against RSV in preclinical studies. A pivotal study assessed the efficacy and safety of motavizumab versus palivizumab for prevention of RSV hospitalization in high-risk infants. Because
Conflict of interest
Dr. Ramilo has served as a consultant for Abbvie, Gilead and Alios.
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Cited by (32)
M2-2 gene as a new alternative molecular marker for phylogenetic, phylodynamic, and evolutionary studies of hRSV
2022, Virus ResearchCitation Excerpt :The pivotal cause of ARIs is the human respiratory syncytial virus, hRSV (Nair et al., 2010). A study reported that up to 33.8 million people are affected, mainly children under five years (e.g., especially newborns), with 22% of these infections associated with the lower respiratory tract (Rodriguez and Ramilo, 2014). The hRSV belongs to the Orthopneumovirus genus and the Pneumoviridae family (Adams et al., 2016).
Epicutaneous immunization using synthetic virus-like particles efficiently boosts protective immunity to respiratory syncytial virus
2021, VaccineCitation Excerpt :Respiratory syncytial virus (RSV) is the most common cause of hospitalization in children under 5 years of age [1–3].
Developmental plasticity in the neural control of breathing
2017, Experimental NeurologyNon-invasive epicutaneous vaccine against Respiratory Syncytial Virus: Preclinical proof of concept
2016, Journal of Controlled ReleaseCitation Excerpt :The development of a safe and effective RSV vaccine for infants in the first six months of life is a public health challenge for reducing the severe burden of RSV-associated respiratory diseases, especially bronchiolitis and hospitalizations. Globally, it is estimated that RSV causes > 30 million lower respiratory tract infections each year resulting in > 3 million hospitalizations, making it the most common cause of hospitalizations in children under 5 [1]. Moreover, severe RSV incidence is highest in infants younger than 5 months.
Acute bronchiolitis and chest physiotherapy: The end of a reign
2015, Journal Europeen des Urgences et de ReanimationAcute bronchiolitis and chest physiotherapy: The end of a reign
2015, Archives de Pediatrie