Related Experiment Video
Updated: Feb 17, 2026
An In vitro Model to Study Immune Responses of Human Peripheral Blood Mononuclear Cells to Human Respiratory Syncytial Virus Infection
Published on: December 10, 2013
Respiratory syncytial virus in Brazilian infants - Ten years, two cohorts
Elinara Wollmeister1, Alfonso Eduardo Alvarez2, Juliana Cristina Santiago Bastos3
1Department of Pediatrics, Faculty of Medical Sciences, University of Campinas - Unicamp, São Paulo, Brazil.
Insights
Acute viral bronchiolitis (AVB) in infants shows a significant increase in respiratory syncytial virus (RSV) over ten years. This study compared infant cohorts, finding changes in viral prevalence but not overall severity.
Area of Science:
- Pediatrics
- Infectious Diseases
- Epidemiology
Background:
- Acute viral bronchiolitis (AVB) is a common respiratory infection in infants, leading to significant hospitalizations and healthcare burdens.
- Understanding trends in AVB etiology and epidemiology is crucial for public health initiatives.
Purpose of the Study:
- To compare epidemiologic factors and viral causes of AVB in two infant cohorts separated by a decade (2004 vs. 2014).
Main Methods:
- Retrospective analysis of two infant cohorts (n=142 in 2004, n=172 in 2014) diagnosed with AVB.
- Clinical data and nasopharyngeal secretions for viral genetic screening were collected.
- Comparative statistical analysis was performed on demographic, clinical, and etiological factors.
Main Results:
- A significant increase in respiratory syncytial virus (RSV) detection was observed between 2004 (33.1%) and 2014 (70.3%).
- Infant cohort in 2014 showed lower birth weight and gestational age, and a shift in seasonality towards April.
- Hospitalization duration, mechanical ventilation needs, and mortality rates remained similar, but comorbidities were higher in the 2004 cohort.
Conclusions:
- While RSV prevalence increased significantly over ten years, AVB severity indicators like hospitalization time and mortality did not worsen.
- Further research into virology, immunology, genetic variants, and immune system maturation is recommended for managing AVB, particularly RSV-related cases.
Background:
Each year, a considerable amount of children will experience at least one episode of acute viral bronchiolitis (AVB) during their first year of life. About 10% of them will be hospitalized, with significant physical and economic burdens.
Objectives:
To compare two cohorts of infants with AVB, from same region, in a ten-year interval, regarding epidemiologic factors and viral etiology.
Study Design:
Cohorts: 142 (2004) and 172 (2014) infants at ages zero to 12 months; clinical diagnosis of AVB; medical care in hospital and genetic screening of nasopharyngeal secretion for respiratory viruses.
Results:
The comparative analysis showed a difference in the percentage of respiratory syncytial virus (RSV) positive patients [2004 (33.1%); 2014 (70.3%)] (p<0.01). No differences were noted regarding gender, breastfeeding, tobacco exposure, crowding and maternal education. There was a difference as to the month of incidence (seasonality) of AVB (higher in April 2014). There was a higher age at attendance in the first cohort, and lower birth weight and gestational age ratios in the second cohort (p<0.05). There were no differences in hospitalization time, need of mechanical ventilation and number of deaths, however a difference regarding co-morbidities was noted (higher in 2004) (p<0.001).
Conclusion:
None of the analyzed variables had an impact on severity features. Virology and immunology must be considered in this kind of situation, by studying genetic variants and the maturation of the immune system in AVB by RSV or other viruses.
Related Concept Videos
01:31Common Respiratory Disorders
Upper respiratory disorders impact the airways above the vocal cords, encompassing areas like the nose, sinuses, and throat. Various conditions fall under this category, including the common cold and allergic rhinitis. These disorders can stem from several causes,...
01:21Acute Respiratory Failure-II
The underlying physiological abnormalities that contribute to hypoxemic respiratory failure include:
01:03Rous Sarcoma Virus (RSV) and Cancer
RSV is a retrovirus that contains two copies of a plus-strand RNA genome. Its genome consists of four main open...
01:15Respiratory Volumes
Tidal Volume (TV) Tidal volume (TV) is the air inhaled or exhaled in a...
01:24Respiratory Capacities
One key metric is the Inspiratory Capacity (IC), which represents the maximum amount of air that can be inhaled with full effort. IC is calculated by summing the tidal volume and inspiratory reserve volume, typically ranging from 2.4 to 3.6 liters.
The Functional Residual Capacity (FRC) represents the air in the...
01:21Acute Respiratory Failure-I
Definition: It is defined by specific criteria based on blood gas measurements. Hypoxemia happens when the partial pressure of oxygen (PaO2) falls below 60 mmHg. At the same time,...