Respiratory Infections in Young Children

The goal of this observational study is to learn about the causes, severity, and long-term effects of respiratory tract infections (RTIs) in young children from birth to five years of age in Colombia and Panamá. The main questions it aims to answer are: How often do respiratory infections occur in children under two years old, and which viruses or bacteria cause them? Why do some children develop more severe infections than others? Do early infections or vaccinations change how the immune system responds to future illnesses? How do viruses and bacteria interact in the respiratory tract to influence disease severity and long-term respiratory health? Researchers will follow newborns from birth until age five to understand how respiratory infections develop and affect children's health over time. Participants will not receive any experimental treatment. Families who join the study will: Be contacted twice a week through a phone app or phone calls to check for symptoms of respiratory infection. Attend in-person visits if their child becomes ill and every six months for routine follow-up. Provide nasal and blood samples during illness episodes so researchers can identify the viruses or bacteria causing infection and study how the immune system responds. This study began in May 2024 and is being conducted in Cali, Colombia, and Panamá City, Panamá. The research team plans to continue to include participants and continue active follow-up until the children reach five years of age. The information collected will help scientists and health professionals understand how different pathogens cause respiratory infections, what factors increase the risk of severe illness, and how early infections may influence long-term lung health. The study's findings will support future efforts to prevent and treat respiratory diseases in young children.