Pattern and risk factors of acute respiratory infections in children under five years: A hospital-based cross-sectional observational study.

Background: Acute respiratory infections (ARIs) remain one of the leading causes of morbidity and hospitalization among children under five years, particularly in low- and middle-income countries. Identifying demographic, environmental, and nutritional risk factors is essential to guide preventive strategies and optimize health outcomes. Objectives: To determine the clinical pattern and assess the key risk factors associated with acute respiratory infections in children under five years of age attending a tertiary care hospital. Methods: A hospital-based observational study was conducted among 100 children aged below five years clinically diagnosed with ARI. Data were collected using a structured proforma covering demographic details, clinical presentation, nutritional and immunization status, and environmental conditions. Statistical analysis was performed using descriptive measures and percentage distribution. Results: The majority of cases occurred in the 1–3-year age group (46%), with males (58%) slightly predominating. Upper respiratory tract infections (64%) were more frequent than lower respiratory infections (36%). The most common presenting symptoms were cough (94%), fever (86%), and nasal discharge (72%). Undernutrition was identified in 42% of children, and 58% belonged to the lower socioeconomic class. Major risk factors included indoor air pollution (68%), overcrowding (52%), passive smoking (36%), and lack of exclusive breastfeeding (46%). Incomplete immunization was observed in 28%, and low birth weight (<2.5 kg) in 34%. ARI incidence peaked during the monsoon and winter months (62%). The mean hospital stay was 4.6 ± 2.1 days, with full recovery in 92% of cases and no mortality reported. Conclusion: Acute respiratory infections in children were predominantly associated with modifiable risk factors such as undernutrition, indoor air pollution, overcrowding, and incomplete immunization. Most cases were mild and preventable through early intervention. Recommendations: Community-level interventions such as promoting exclusive breastfeeding, complete immunization, improving