Characterization of indoor bioaerosols from a hospital ward in a tropical setting
Objectives: Study was conducted to assess whether temporal variation exists in airborne microbial concentrations of a hospital ward (west-Chennai, India) using active and passive methods, and characterise the microorganisms.
Methods: Air samples (duplicates) were collected simultaneously using exposed-plate, impingement (BioSampler) and filtration (personal sampling filter cassette loaded with gelatin filter) methods over different periods of the year. Bacterial plates were incubated at 37°C and observed for growth after 48h; fungal plates were incubated at 25°C and 37°C and observed upto 7 days. Microorganisms were identified using standard microbiological procedures.
Results: Microbial loads were found to vary with the sampling method. Concentrations of bacteria were higher (exposedplate: 45–150 CFU/plate; impingement: 1.12E+03–1.6856E+05 CFU/m3; filtration: 3.788E+03–1.91111E+05 CFU/m3) than fungi (exposed-plate: 0–13 CFU/plate; impingement: 0–3.547E+03 CFU/m3; filtration: 0–1.515E+04 CFU/m3). Coagulase-negative Staphylococci and Micrococci were the predominant Gram-positive cocci in active and passive samples. Enterobacter and Pseudomonas were the predominant Gram-negative bacilli. Among fungi, Aspergillus niger was isolated throughout the year. There was no significant temporal variation in airborne microbial loads irrespective of methods.
Conclusions: Exposed-plate method was found to capture microorganisms efficiently with little variation in duplicate samples, suggesting its use in hospitals for preliminary assessment of indoor air quality and determine pathogenic microorganisms due to particle fall-out.
Key words: Indoor air, bioaerosols, hospital ward, tropical setting
While African Health Sciences has been freely accessible online there have been questions on whether it is Open Access or not. We wish to clearly state that indeed African Health Sciences is Open Access. There are key issues regarding Open Access needing clarification for avoidance of doubt:
- 1. Henceforth, papers in African Health Sciences will be published under the CC BY (Creative Commons Attribution License) 4.0 International. See details on https://creativecomons.org/)
- 2. The copyright owners or the authors grant the 3rd party (perpetually and in advance) the right to disseminate, reproduce, or use the research papers in part or in full, format/medium as long as:
- No substantive errors are introduced in the process
- Attribution of authorship and correct citation details are given
- The referencing details are not changed.
Should the papers be reproduced in part, this must be clearly stated.
- 3. The papers will be freely and universally accessible online in an easily readable format such as XML in at least one widely recognized open access repository such as PUBMED CENTRAL.
B. ABRIDGED LICENCE AGREEMENT BETWEEN AUTHORS AND African Health Sciences
I submitted my manuscript to African Health Sciences and would like to affirm that:
1.0 I am authorized by my co-authors to enter into these arrangements.
2.0 I guarantee, on behalf of self and co-authors:
- That the paper is original, and has not been published in any other peer-reviewed journal; nor is it under consideration by other journal (s). It does not infringe existing copyright or any other person’s rights
- That we are/I am the sole author(s) of the paper and with authority to enter into this agreement. My granting rights to African Health Sciences is not in breach of any other obligation
- That the paper contains nothing unlawful, or libelous. Nor anything that would constitute a breach of contract, confidence or commitment given to secrecy, if published
- That I/we have taken care to ensure the integrity of the article.