The Pneumonia Etiology Research for Child Health (PERCH) study is a cross-national, case-control investigation aimed at unraveling the underlying causes of pneumonia in children under five years of age, necessitating hospitalization across seven diverse countries. Through meticulous analysis of microbial pathogens and contextual factors, the study seeks to delineate the complex triggers driving pneumonia's escalation to a critical stage demanding urgent medical care. By employing metagenomics, this project specifically focuses on profiling upper respiratory tract microbial communities in The Gambia, South Africa, and Mali. Through metagenomic sequencing the extracted DNA, the project aims to decode the genetic composition of these microorganisms, ultimately uncovering microbiological contributors to pneumonia severity. The ultimate goal is to translate these insights into improved strategies for enhancing child health outcomes in these regions.