Association Of Classroom Ventilation And Overcrowding With Prevalence Of Upper Respiratory Tract Infections Among School Going Students

Abstract

Upper respiratory tract infections (URTI) are one of the most common acute illnesses worldwide (1). Types of URTI include common cold and influenza. Children, particularly in the preschool years, seem especially vulnerable; they are estimated to average from eight to ten colds per year (2). Upper respiratory tract infection is a common illness, with high prevalence in children <10 years of age globally (3). Repeated infection has a major impact on children’s lives, with missed days of school and additional visits to health care providers. The relationship between URTIs and school absenteeism is robust. School absenteeism due to an acute respiratory illness is common in children, and studies show that about 50% of children who miss 1 to 2 days of school do so because of a respiratory illness (4).

These infections also have been associated with increased use of health care and unnecessary prescriptions for antibiotics (5). The students spend most of their time in classrooms, many of which are over-crowded with classes of between 20 and 30 pupils (6). Crowded places with poor ventilation cause rapid elevation of carbon dioxide (CO2) levels and stagnant air (7). Indeed, CO2 concentrations in crowded classrooms frequently exceed 1000 ppm, which is far below the recommended ventilation rates (8). Moreover, insufficient air exchange causes increased humidity and the accumulation of respiratory aerosols (9). The high density of occupants and poor ventilation increase the re-breathed air (10) which makes airborne transmission of the disease easier among students.