VRS, or ‘virus of babies’
In preterm children syncytial virus is the leading cause of infections of the Airways in under two years
Respiratory syncytial virus usually causes an infection in the respiratory system, and although it is usually mild character, there are risk groups where the consequences may take more serious. According to the Spanish society of gynaecology, respiratory syncytial virus is responsible for, each year, about 25,000 consultations of emergency and 15,000 hospitalizations of preterm infants, particularly since the month of October to April. In addition, recently, a group of us researchers has linked this pathogen with the later development of asthma.
While respiratory syncytial virus infection can occur at any time, the period spanning from October to April is which shows an increase in the number of cases. In the North of Spain, the period of highest incidence begins earlier, in September, and ends shortly after, between April and may. According to the Spanish society of gynaecology (SEN), about 75% of infants comes into contact with the virus during their first year of life, figure rising to 100% after two years.
Three risk factors
Within the framework of the international meeting of Perinatal Medicine held on 21 September in Istanbul (Turkey), which has brought together experts in neonatology, Pediatrics and Pneumology from around the world, have presented the results of the epidemiological study FLIP-2, prepared by the Iris Group (Infant Respiratory Infection by RSV, in its English acronym) of the SEN. The study sought to analyze the role of risk factors associated with RSV infection, and that can lead to the hospitalization of the infant. The data obtained shows that children born between weeks 32 and 35 of gestation are 3.11 times more likely to be hospitalized for RSV infection when they present at least two risk factors, compared with those who do not have any.
The study has been conducted on a sample of 5.441 children of 37 Spanish hospitals. Josep Figueras Aloy, neonatologist of the Hospital Clínic of Barcelona and coordinator of the FLIP-2, points out that there are three significant risk factors: that the baby is born between 15 July and 15 December, having a brother school–age or that the child goes to day care, and smoking of the mother during pregnancy, which can injure the fetal lung.
Asthma in adulthood
Babies born prematurely are three times more likely to be infected by VRS because defences are less
In the long run, the RSV infection can cause asthma processes or alterations in pulmonary function in adulthood. This is the conclusion that scientists have reached Southwestern University (Dallas, USA). However, Octavio Ramilo, Coordinator of the study, specified in the ‘Advances in the prevention of RSV infection’ Symposium, held recently in Madrid, «no predisposing to suffer classic asthma atopy, but an important asthma which makes that children continue to bronchospasm and wheezing to ten years».
The expert explained that the virus originates not only bronchiolitis, but when the acute phase exceeds lung continues to present specific bronchial hyper-responsiveness, even after several months. The study also revealed that the early administration of prophylactic palivizumab monoclonal antibody is associated with a decrease of cytokines, proteins that are involved in inflammatory, including processes that affect the lungs. By suppressing the virus and inflammation, sequelae of asthma are reduced in the short term, says Ramilo.
While there is no vaccine to deal with the infection, experts recommend the use of palivizumab. According to currently available data, this active ingredient could prevent infection during the first year of the baby and lessen the effects of the virus in asthma. From the SEN also supported monthly palivizumab administration as the most effective treatment in populations at risk of infection severe by VRS. The Administration is intramuscular during the months of the epidemic season. The goal is to provide the child antibodies that curb the activity of the virus and neutralize their action.