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Published on: February 13, 2015
The housefly (Musca domestica) as a carrier of pathogenic microorganisms in a hospital environment
R Fotedar1, U Banerjee, S Singh
1Department of Microbiology, All India Institute of Medical Sciences, New Delhi.
Abstract:
Houseflies have long been regarded as potential carriers of microorganisms. Since pathogenic microorganisms are widespread in the hospital environment, there is abundant opportunity for flies to become contaminated and, in turn, to contaminate the patient environment. In the present study, an attempt was made to isolate and identify pathogenic bacteria, fungi and parasites from the housefly Musca domestica collected in the surgical ward of the All India Institute of Medical Sciences Hospital and also in a remote residential area located 5 km from the hospital. A total of 113 flies were collected: 65 from a surgical ward (test) and 48 from a residential area for comparison. Ten genera of bacteria were isolated from the test group of flies compared with nine from the control group. In primary isolations, it was observed that the load of bacteria carried by the test group of flies was significantly more (P less than 0.001) than for the control flies. Pseudomonas aeruginosa, Enterococcus faecalis and viridans streptococci were isolated only from the test flies. The isolation rate of Staphylococcus aureus was significantly higher (P less than 0.001) in test houseflies than in the control houseflies. There was no significant difference in isolation of parasitic ova and cysts from test and control houseflies. Candida spp. were isolated in almost equal numbers from both groups of houseflies, yet none of these was Candida albicans. Houseflies therefore may act as vectors of potentially pathogenic bacteria in a hospital environment.
Insights
Houseflies in hospital surgical wards carry significantly more bacteria, including dangerous pathogens like Staphylococcus aureus, than those in residential areas. This highlights their role as potential vectors for spreading infections in healthcare settings.
Area of Science:
- Microbiology
- Medical Entomology
- Infectious Diseases
Background:
- Houseflies (Musca domestica) are known potential carriers of microorganisms.
- Hospital environments harbor widespread pathogenic microorganisms, increasing contamination risk for flies and patients.
Purpose of the Study:
- To isolate and identify pathogenic bacteria, fungi, and parasites from houseflies collected in a hospital surgical ward and a control residential area.
- To assess the role of houseflies as potential vectors of microorganisms in a hospital setting.
Main Methods:
- Collected 113 houseflies: 65 from a surgical ward (test) and 48 from a residential area (control).
- Isolated and identified bacteria, fungi (Candida spp.), and parasites (ova and cysts) from collected flies.
- Compared microbial loads and specific pathogen isolation rates between test and control groups.
Main Results:
- Significantly higher bacterial load (P < 0.001) found in flies from the surgical ward compared to control flies.
- Specific pathogenic bacteria, including Pseudomonas aeruginosa, Enterococcus faecalis, viridans streptococci, and Staphylococcus aureus (P < 0.001), were more prevalent in surgical ward flies.
- No significant difference in isolation rates for parasitic ova and cysts; Candida spp. were found in similar numbers, with no Candida albicans isolated.
Conclusions:
- Houseflies in hospital surgical wards harbor a greater quantity and variety of potentially pathogenic bacteria.
- Houseflies can act as vectors for transmitting harmful bacteria within hospital environments.
- Further research may be needed to explore fungal and parasitic transmission by houseflies in healthcare settings.
