Bacterial community of indoor air dust collected from selected primary public schools of Metro Manila

Abstract

Indoor air quality becomes a public health concern especially when people spend most of their time indoors thereby exposing themselves to possible threats. Assessment of bacterial community structure in indoor dust can therefore aid in improving indoor air quality particularly those associated with disease-causing bacteria. This study sought to determine the bacterial community of indoor dust collected from five (5) purposively selected primary public schools in Metro Manila using the gravimetric method and subsequent cultural and physiological characterization. Sixteen (16) culturable groups of bacteria, with Bacillus sp. being the most frequently distributed among the five schools were obtained from the samples collected. Three other groups of Gram positive bacteria, including Corynebacterium sp., Staphylococcus aureus and coagulase-negative Staphylococcus were also detected, while the rest were mostly Gram negative bacteria belonging to the family Enterobacteriaceae. While the majority of the bacteria identified are part of the normal human flora, others are potentially opportunistic pathogens that can pose health problems. In light of these findings, possible short-term solutions may focus on ensuring adequate ventilation, filtration systems, fixing of any leaks, proper control of humidity, and regular mechanical cleaning of the said classroom facilities.