Bronchopulmonary dysplasia (BPD) is the result of a complex process in which several prenatal and/or postnatal factors interfere with lower respiratory tract development, leading to a severe, lifelong disease. In this review, what is presently known regarding BPD pathogenesis, its impact on long-term pulmonary morbidity and mortality and the available preventive and therapeutic strategies are discussed. Bronchopulmonary dysplasia is associated with persistent lung impairment later in life, significantly impacting health services because subjects with BPD have, in most cases, frequent respiratory diseases and reductions in quality of life and life expectancy. Prematurity per se is associated with an increased risk of long-term lung problems. However, in children with BPD, impairment of pulmonary structures and function is even greater, although the characterization of long-term outcomes of BPD is difficult because the adults presently available to study have received outdated treatment. Prenatal and postnatal preventive measures are extremely important to reduce the risk of BPD. Bronchopulmonary dysplasia is a respiratory condition that presently occurs in preterm neonates and can lead to chronic respiratory problems. Although knowledge about BPD pathogenesis has significantly increased in recent years, not all of the mechanisms that lead to lung damage are completely understood, which explains why therapeutic approaches that are theoretically effective have been only partly satisfactory or useless and, in some cases, potentially negative. However, prevention of prematurity, systematic use of nonaggressive ventilator measures, avoiding supraphysiologic oxygen exposure and administration of surfactant, caffeine and vitamin A can significantly reduce the risk of BPD development. Cell therapy is the most fascinating new measure to address the lung damage due to BPD. It is desirable that ongoing studies yield positive results to definitively solve a major clinical, social and economic problem.

In order to evaluate the role of Mycoplasma pneumoniae and Chlamydia pneumoniae, we studied 613 children aged 2–14 years who were hospitalized for community-acquired lower respiratory tract infections (LRTIs). The patients were enrolled in the study by 21 centers in different regions of Italy from May 1998 through April 1999. Paired serum samples were obtained on admission and after 4–6 weeks to assay the titers of M. pneumoniae and C. pneumoniae antibodies. Nasopharyngeal aspirates for the detection of M. pneumoniae and C. pneumoniae were obtained on admission. Acute M. pneumoniae infections in 210 patients (34.3%) and acute C. pneumoniae infections in 87 (14.1%) were diagnosed. Fifteen of the 18 children with M. pneumoniae and/or C. pneumoniae infections whose treatments were considered clinical failures 4–6 weeks after enrollment had not been treated with macrolides. Our study confirms that M. pneumoniae and/or C. pneumoniae plays a significant role in community-acquired LRTIs in children of all ages and that such infections have a more complicated course when not treated with adequate antimicrobial agents.

To face the COVID-19 outbreak, a wide range of non-pharmaceutical interventions (NPIs) aimed at limiting the spread of the virus in communities, such as mask-wearing, hand hygiene, social distancing, travel restrictions, and school closures, were introduced in most countries. Thereafter, a significant reduction of new asymptomatic and symptomatic COVID-19 cases occurred, although there were differences between countries according to the type and duration of the NPIs. In addition, the COVID-19 pandemic has been accompanied by significant variations in the global incidence of diseases due to the most common non-SARS-CoV-2 respiratory viruses and some bacteria. In this narrative review, the epidemiology of the most common non-SARS-CoV-2 respiratory infections during the COVID-19 pandemic is detailed. Moreover, factors that could have had a role in modifying the traditional circulation of respiratory pathogens are discussed. A literature analysis shows that NPIs were the most important cause of the general reduction in the incidence of influenza and respiratory syncytial virus infection in the first year of the pandemic, although the different sensitivity of each virus to NPIs, the type and duration of measures used, as well as the interference among viruses may have played a role in modulating viral circulation. Reasons for the increase in the incidences of Streptococcus pneumoniae and group A Streptococcus infections seem strictly linked to immunity debt and the role played by NPIs in reducing viral infections and limiting bacterial superimposed infections. These results highlight the importance of NPIs during pandemics, the need to monitor the circulation of infectious agents that cause diseases similar to those caused by pandemic agents, and the need to make efforts to improve coverage with available vaccines.

Recent studies indicate that influenza can be clinically important in otherwise healthy children. However, the interpretation of many studies is limited because of lack of laboratory confirmation of influenza-like illnesses. Therefore it is difficult to conclude whether the socioeconomic impact of influenza justifies vaccinating all children regardless of age or underlying chronic disorders. We prospectively collected data from 3771 children younger than 14 years of age presenting to emergency departments or primary care pediatricians with symptoms of respiratory tract infection during the influenza season of 2001 to 2002. Influenza infections were verified by virus culture or polymerase chain reaction. We additionally randomized 303 children age 6 months to 5 years to receive either influenza vaccine (n = 202) or no vaccination (n = 101) before the influenza season. The socioeconomic impact of influenza was assessed for both the participating children and their household contacts. Influenza was documented in 352 (9.3%) of the 3771 children. Compared with influenza-negative children, children with influenza had longer durations of fever and absenteeism from day care or school (P < 0.0001). Further the numbers of medical visits, missed work or school days and the need for help at home to care for the sick children were higher among the household contacts of influenza-positive children (P < 0.0001). Influenza vaccination reduced significantly the direct and indirect influenza-related costs in healthy children and their unvaccinated family members. The findings of this study support a wider use of influenza vaccine in healthy children of all ages to reduce the socioeconomic burden of influenza on the community.