Infections of the lungs and respiratory system of a child usually affect children under 2 years of age. It can be caused by various types of viruses, the most common bronchiolitis being the so-called respiratory syncytial virus (RSV). In this case, if a child suffers from it before the age of 3, the risk of developing asthma can increase by 2.5 times, according to Antonio Nieto, a doctor from the La Fe Health Research Institute in Valencia.

Most cases are mild, and in many cases people don’t usually go to a hospital emergency room, so the expert warned that it’s “difficult” to know exactly what the incidence is at present. Although from what is known at the moment, the incidence of bronchiolitis in Spain in 2022 is twice as high as in the period 2019-2020, 12-15 times higher than in the period 2020-21 (under complete lockdown due to COVID-19 pandemic). ), and 50 percent higher than last year.

According to the expert, antiviral drugs also did not show stable effectiveness. “It must be taken into account that the price of monoclonal antibodies against RSV, such as palivizumab, limits their use to risk groups (children with congenital heart defects or children with severe bronchopulmonary dysplasia), in addition to the fact that although RSV is a virus that in most cases causes bronchiolitis (especially in infants under 6 months of age), in some cases other viruses such as rhinovirus or metapneumovirus are responsible. Therefore, since palivizumab is a specific anti-RSV drug, it will not be effective in these other cases,” he said.

The possibility of preventing viral infections through the use of vaccines aimed at training innate immunity is considered. These conceptually new vaccines provide non-specific but long-term protection while promoting adaptive responses against possible co-infections.

Nieto emphasized that the results of a growing number of clinical studies, together with advances in knowledge of the innate immune response to pathogens and new concepts such as “trained immunity”, have changed the perception of innate immunity as part of the “inferior”, emergency immunity, lack of immunological memory leading to the development of a new generation of bacterial-based broad-spectrum antiviral vaccines.