Antibody levels against respiratory syncytial virus fusion protein conformations and lack of association with life-threatening infection in previously healthy infants.

Background: Humoral immune response against the pre-fusion (pre-F) conformation of respiratory syncytial virus (RSV) F protein has been proposed to play a protective role against infection. An RSV pre-F maternal vaccine has been recently approved in several countries to protect young infants against RSV. We aimed to assess serum IgG titers against the pre-F and post-F conformations of RSV F protein and their association with life-threatening RSV disease (LTD) in previously healthy infants.

Genetic Susceptibility to Life-threatening Respiratory Syncytial Virus Infection in Previously Healthy Infants.

Background: Genetic background may be an important host determinant of respiratory syncytial virus (RSV) disease severity, but full characterization of susceptibility genes remains unclear. This study aimed to assess the presence of specific single-nucleotide polymorphisms (SNPs) in selected genes codifying for different components of the antiviral innate immune response, to determine their role for developing RSV life-threatening disease (LTD).

Methods: Prospective cohort study including previously healthy full-term infants hospitalized with a first RSV infection during 2017-2018.

Respiratory Failure and Death in Vulnerable Premature Children With Lower Respiratory Tract Illness.

Background: Efforts to better understand the risk factors associated with respiratory failure (RF) and fatal lower respiratory tract infection (LRTI) in premature children in developing countries are necessary to elaborate evidenced-based preventive interventions. We aim to characterize the burden of respiratory syncytial virus (RSV) and human metapneumovirus (hMPV) LRTI in premature children and determine risk factors for RF and fatal illness in a vulnerable population.

Methods: This is a prospective, population-based, cross-sectional study.

Role for Maternal Asthma in Severe Human Metapneumovirus Lung Disease Susceptibility in Children.

Background: Severity of human metapneumovirus (hMPV) lower respiratory illness (LRTI) is considered similar to that observed for respiratory syncytial virus (RSV). However, differences in severity between these pathogens have been noted, suggesting the degree of illness may vary in different populations. Moreover, a potential association between hMPV and asthma also suggests that hMPV may preferentially affect asthmatic subjects.

Clinical and epidemiological impact of respiratory syncytial virus and identification of risk factors for severe disease in children hospitalized due to acute respiratory tract infection.

Introduction: Severe acute respiratory tract infection (ARTI) is a very common cause of hospitalization in pediatrics; respiratory syncytial virus (RSV) is the major etiologic agent. Accurately defining the burden of RSV life-threatening disease (LTD) and its risk factors is a challenge.

Objectives: To know the impact of RSV in children hospitalized due to ARTI and describe the risk factors for LTD.

[Dengue outbreak in Buenos Aires, Argentina, 2016: Clinical and hematological features in children].

Unlabelled: Dengue is the human arbovirus with the highest morbidity and mortality in the world. The largest outbreak of dengue in Buenos Aires, Argentina, occurred during 2016.

Objective: To describe clinical and hematological features in children with confirmed dengue infection.

Clinical and epidemiological impact of varicella infection in children prior to the introduction of the varicella vaccine in the national immunization schedule of Argentina.

Introduction: In Argentina, an estimated 400 000 varicella cases occur annually. Given the under-recording of existing cases, the actual burden of disease is unknown.

Objective: To assess the burden of varicella before the introduction of the varicella vaccine in the national immunization schedule.

Alcohol during pregnancy worsens acute respiratory infections in children.

Aim: This study explored whether alcohol consumption during pregnancy increased the risk of life-threatening respiratory infections in children.

Methods: We prospectively evaluated children under the age of two years admitted to hospitals in Buenos Aires, Argentina, with severe acute respiratory infections during the winters of 2011 and 2012. Information on maternal alcohol consumption during the third trimester of pregnancy was collected using standardised questionnaires and categorised as never, low if it was once a week and high if it was equal or more than once a week.

TLR4 genotype and environmental LPS mediate RSV bronchiolitis through Th2 polarization.

While 30%-70% of RSV-infected infants develop bronchiolitis, 2% require hospitalization. It is not clear why disease severity differs among healthy, full-term infants; however, virus titers, inflammation, and Th2 bias are proposed explanations. While TLR4 is associated with these disease phenotypes, the role of this receptor in respiratory syncytial virus (RSV) pathogenesis is controversial.

Breastfeeding is associated with the production of type I interferon in infants infected with influenza virus.

Background: Breast milk-mediated protection against respiratory viruses is well established. However, protective mechanisms are unclear. Type I interferons (IFN) mediate host defence against respiratory viruses, particularly influenza virus.

[Nasal septal abscess].

A nasal septal abscess (NA) is defined as a collection of pus between the cartilage or bony septum and its normally applied mucoperichondrium or mucoperiostium. It is an uncommon disease which should be suspected in a patient with acute onset of nasal obstruction and recent history of nasal trauma, periodontal infection or an inflammatory process of the rhinosinusal region. We report a case of an 8-year-old boy with bilateral NA caused by community-acquired methicillin-resistant Staphylococcus aureus(MR-CO) in order to emphasize the importance of prompt diagnosis and adequate treatment to prevent the potentially dangerous spread of infection and the development of severe functional and cosmetic sequelae.