Fungal Isolates from the Air Conditioner Filters

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sawakochan
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Fungal Isolates from the Air Conditioner Filters

Hi & Hello,
 
My research mates & I have been having problems on our research about "A Study of the Fungal Isolates from the Air Conditioner Filters of the ICU, DR, LR and Nursery of a private hospital and the ICU and DR of a government hospital in _______.
 
My research mates & I would like to seek help from you.
 
If you are one of the committee who will ask questions what are the frequently asked questions during a research oral defense?
 
This is only a part of our research, below is our Abstract, Research Question, General & Specific Objectives, Results, Discussion, and Conclusion:
 

Title: A Study of the Fungal Isolates from the Air Conditioner Filers of the ICU, DR, LR and Nursery of a private hospital and the ICU and DR of a government hospital in _______.

Background: The Intensive Care Unit (ICU), Labor room (LR), Delivery room (DR) and Nursery rooms (NR) are special areas in the hospital where most immunocompromised patients are confined.
Rationale: The identification of fungal isolates in the air conditioner filters in the special areas.
Objective: To identify the fungi found in the air conditioner filter in the special areas.
Study Design: Descriptive, prevalence study
Study setting:
The study was conducted in two types of hospital: a private hospital, which is controlled by a single practitioner and associates in his or her office and a government hospital, which is administered by the officials of the city.
Study Population: Ten swabs obtained from the air conditioner filters of a private hospital and three swabs from the air conditioner filter of a government hospital.
Maneuver: The swabs obtained were inoculated on Sabouraud’s dextrose agar (SDA) plates and incubated at room temperature. Mixed colonies were further subcultured on SDA plates in order to obtain pure colonies. Once an isolate has been obtained, slide cultures were done for its identification.
Limitation: Out of five hospitals, only one private and one public hospital approved the research proposal and among the special areas in the government hospital, only the air conditioners of the ICU and DR are functioning.
Result: From the air conditioner filters of the specified areas of a private and government hospital, the fungi isolated are as follows: Mucor spp, Rhizopus spp., Penicillium spp., Aspergillus niger , Aspergillus flavus, Aspergillus fumigatus and Aspergillus terreus.
Conclusion:  Based on the results obtained of this study, the researchers conclude that all the isolated fungi are non-pathogenic. Among the isolates, Mucor is isolated with the highest frequency.
 

Research Questions
 
            What are the fungi present in the air conditioner filters of Intensive Care Unit (ICU), Nursery Room (NR), Labor Room (LR) and Delivery Room (DR) of a private hospital and ICU and DR of a government hospital in ______? 
           
General Objective
 
            To determine the fungal isolates present in the air conditioner filters of Intensive Care Unit (ICU), Nursery Room (NR), labor Room (LR) and Delivery Room (DR) of a private hospital and ICU and DR of a government hospital in _______.
 
Specific Objectives
 
1. To identify the fungi isolated from the swab samples obtained.
2. To determine the proportion of fungi isolated in each area of the hospital.
3. To determine the proportion of pathogenic and non-pathogenic fungi isolated.
 

R E S U L T S
 
            There were two (2) hospitals that participated in the study, a private and a government. The private hospital included four (4) areas namely; one (25%) ICU, one (25%) DR, one (25%) Labor Room and one (25%) Nursery as seen in Figure 1 below. On the other hand the government hospital included only one (50%) ICU and one (50%) DR.

 
Figure 2 and 3 depicts the total number of air conditioners in each area of the private and government hospital respectively. There were 4 (40%) air conditioners in the intensive care unit, 3 (30%) in the nursery, 2 (20%) in the delivery room and only one (10%) in the labor room. While in the government hospital there were 2 (66.67%) air conditioners in the intensive care unit and only one (33.33%) in the delivery room.
 

 

 
 
The isolates taken from the air conditioner filters in the different areas of the private and government hospitals are illustrated in Figures 4 and 5 respectively. Of the four (4) air conditioner units in the ICU of the private hospital, fifteen (15) isolates were identified namely; 5 (33.3%) Mucor, 2 (13.3%) Rhizopus, 3 (20.0%) Penicillium, 4 (26.7%) Aspergillus niger, and 1 (6.7%) Aspergillus fumigatus. In the delivery room 5 isolates from 2 units were recovered ( 2 (40.0%) Mucor, 1 (20.0%) Rhizopus, and 2 (40.0%) Aspergillus niger). From the single unit in the Labor room 5 isolates were identified which were 3 (60.0%) Mucor, 1 (20.0%) Rhizopus, and 1 (20.0%) Aspergillus niger, Of the 3 units of the nursery 18 isolates were identified (6 (33.3%) Mucor, 2 (11.1%) Rhizopus, 1 (5.6%) Penicillium, 5 (27.8%) Aspergillus niger, 3 (16.7%) Aspergillus flavus, and 1 (5.6%) Aspergillus terreus).
 

 
On the other hand  in the government hospital, there were only two (2) areas were included. Of the two (2) units of the ICU, 11 isolates were recovered (5 (45.5%) Mucor, 3 (27.3%) Rhizopus, 2 (18.2%) Penicillium, and 1 (9.1%) Aspergillus niger. The only unit of the delivery room only Mucor was identified.

 
All of the fungi isolates taken from the different areas of private and government hospitals are non-pathogenic.
 
 
 
 
 
DISCUSSION
 
            Different fungi were isolated from the swabs obtained from the air conditioner filters of the Intensive Care Unit, Delivery Room, Labor Room and Nursery of a private hospital and Intensive Care Unit and Delivery Room of a Government hospital. The fungi isolated were as follows: Mucor spp, Rhizopus spp., Penicillium spp., Aspergillus niger, Aspergillus flavus, Aspergillus fumigatus and Aspergillus terreus. 
The most frequently isolated fungi in both the private hospital were the Mucor species, followed by Aspergillus niger. Rhizopus came in third, followed by Penicillium and then Aspergillus flavus, Aspergillus terreus and Aspergillus fumigatus. In the government hospital, the commonly isolated fungi were also Mucor, however, it was followed by Rhizopus and Penicillium, and the least isolated was Aspergillus niger.
All of these isolated fungi are non -pathogenic. However, the presence of these isolates from the ICU, DR, LR and Nursery should not be neglected. Patients in these areas have “special needs’ and either have serious diseases like an immune or metabolic defect, or underdeveloped immune system as in the case of newborn in nursery. These fungi can produce infection in circumstances such as immunodeficiency, cancer, organ transplant, neutropenic patients, diabetes, debilitated patients and patients on long term antibiotics, which common situations observed in the ICU and DR. Hence, the isolated fungi are opportunistic pathogens.
Mucor, the fungi that was present in highest frequency in both hospitals, together with Rhizopus can be sources of a disease called Zygomycosis. The condition may affect the gastrointestinal tract or the skin. It usually begins in the nose and paranasal sinuses and is one of the most rapidly spreading fungal infections in humans. 
 
Aspergillus fumigatus and Aspergillus flavus, though not commonly isolated,  should not be taken for granted since it is found to be the most common opportunistic pathogen  in humans. As discussed from a previous study of MILIcA LJALJEVI?-GrBI?, et. al, inhalation of Aspergillus spores leads to multiplication of the fungus in the lungs and subsequent invasive infection that may spread to any organ of the body. Dissemination to the brain, gastrointestinal tract, and other organs occurs in up to 30% of cases.
From ten air conditioner filters in the private hospital and three air conditioners in the government hospital, it was noted that fungi do exist randomly. Mucor and Rhizopus were recovered from all areas of both hospitals except in the DR of the government hospital in which Mucor was the only isolate. Aspergillus niger was abundant in the ICU of the private hospital and was only isolated once in the government hospital. On the other hand, Penicillum was isolated only in the ICU and Nursery in the private hospital and in the ICU of the government hospital.
Results of this research confirmed previous findings that air-conditioning systems are highly linked with fungal pollution of indoor air. The diversity and abundance of fungal species isolated from different air-conditioning systems can be attributed to different ways of maintaining the systems themselves. Based on the results, more fungi were isolated from the ICU of both hospitals compared to the other areas since the last cleaning of air conditioner was done two months ago upon the collection of specimen. However, it was noted that it was in the Nursery where almost all the isolates were found with great diversities, although the air conditioners were being cleaned one month ago.
 
 
 
 
CONCLUSION
 
Many microorganisms exist in the environment such as fungi, which are organisms that are commonly present in the surroundings. The air conditioner filters in ICU, DR, of a government and ICU, DR, NR in a private hospital in ______ harbours the following fungi: Mucor spp, Rhizopus spp., Penicillium spp., Aspergillus niger, Aspergillus flavus, Aspergillus fumigatus and Aspergillus terreus. Among the isolates, Mucor exists with the highest frequency.  All of the fungal isolates are non-pathogenic but opportunistic pathogens.
 
With this study, it shows that fungi should not be ignored from being one of the disease-causing microorganisms most importantly that they can be spread through air. Although it is impossible to eliminate the existence of fungi for they are found in the environment it can be minimized by proper maintenance of the air conditioner units to avoid fungal contamination of the air in these areas of hospitals where patients are in immunologically depressed and of which these fungi could pose a threat to patients occupying the area. The development of infection depends however on the fungus that caused the infection and on the immune system of the patient.

Jorge1907
Jorge1907's picture
 I'd ask 

 I'd ask 
1) why do you think AC filters are a relevant surrogate for what's in hospital air?  We don't know how long each flter was there - and it appears you had no seasonal consideration or repeat filters.  Assuming these filters removed fungal elements from air that was going into these areas - I'd ask what is in these specific areas themselves - any settle plate data? any surface swabs?  People and their garments, food, other air ingress all may contribute.  What kind of fungal diseases (esp. nosocomial) were reported during these filter use.  
2) Where is your reference list?  AC's in particular and hospital air in general have been the subject of existing mycological studies.  For example "The most frequently isolated fungi in both the private hospital were the Mucor species, followed by Aspergillus niger. Rhizopus came in third, followed by Penicillium and then Aspergillus flavus, .." what is the ref?  Was it from a review article?  4 or 5 good studies or what?
3) Since you found little of significance, it's less of an issue but you should know what was recoverable from filters before they were installed.  You failed to describe them - some filters include antimicrobial treatments.  You also failed to validate you can get all the fungi off filters.  Others might be present but removed for culture at different efficiencies.
4) You refer to Mucor as nonpathogenic in one paragraph and in a following paragraph you refer to it as an etiologic agent of  zygomycosis.
5)  I'd challenge the numbers and distribution presented on graphs for significance.  You offer no statistical treatment of data and the differences are pretty small in any case.

Generally, this is  a snapshot observation of fungi from a single set of filters used for unreported times.   The only data of note would be what you found and that is limited since it might change next week or next season.