Clinical Research Directory

CARE-ID: Dynamics of Respiratory Infections in Children and Transmission in Households and Schools

Viral respiratory tract infections are very common in children. They contribute to missed time in school, work disruption for caregivers and can also cause severe illness requiring hospitalization and rarely death. In the 2022-2023, influenza, RSV and SARS-CoV-2 viruses infected a large number of children which strained the pediatric healthcare system in many jurisdictions. Unfortunately, there continues to be limited data on duration of infectiousness and transmission risk of these viruses to inform public health decisions during times when there is significant circulation of these viruses.

Impact of Bacterial Expression and Immune Response in the Severity of Pertussis

The resurgence of pertussis is associated with an evolutionary mechanism under the pressure of current acellular vaccines, with a possible impact on vaccine effectiveness and disease expression. Little is known about the mechanisms involved in the clinical variability of pertussis, including its most severe malignant form observed in infants (mortality between 50-80%). The main challenges are: (i) the lack of knowledge about the gene expression of B. pertussis strains currently circulating during human infection, incorporating evolutionary changes and vaccine-induced selective pressure; (ii) the poor understanding of the variability in clinical expression of pertussis, and (iii) the lack of biomarkers to predict disease severity or prognosis in infants. An integrative strategy combining a clinical, microbiological, immunological and 'omic' approach from a prospective cohort of children with pertussis will be used to identify 1. 'in situ' expression profiles of B. pertussis genes and proteins incorporating recent evolutionary changes and 2. a systemic and respiratory immune signature in B. pertussis-infected children according to severity. Results should furthermore serve as a prerequisite for the identification of severity biomarkers and new vaccine antigen candidates taking into account specific immune responses in infants.