Research Article

Assessment of bacterial contamination of toilets and bathroom doors handle/knobs at Daeyang Luke hospital

Frank Ngonda*

Daeyang University, P.O. Box 30330, Lilongwe, Malawi

*For correspondence

Mr. Frank Ngonda,

Daeyang University, P.O. Box 30330, Lilongwe, Malawi.











Received: 14 June 2017

Revised: 03 July 2017

Accepted: 04 July 2017


Objective: The aim of the study was to determine the level of bacterial contamination of door handles/knobs of toilets and bathrooms at Daeyang Luke Hospital.

Methods: Fomite can be described as a non-living object capable of carrying infectious organism and it is considered as one of the major source of spread of hospital acquired infection. In this study, door handles/knobs were swabbed with sterile swab stick moistened with sterile water. The content was evenly transferred to nutrient agar petric dish and then incubated for 24 hours at 37˚C. The study was done between the months of May to August 2016.

Results: The results of the study showed that during the period of study there was 41.6% bacterial contamination with the female medical and surgical ward toilets being more contaminated as compared to staff toilets. Private room bathrooms were more contaminated during the period of study as compared to the staff room bathrooms that were less contaminated. Among the bacterial contaminant isolated and identified, Staphylococcus aureus had the highest prevalence followed by Escherichia coli, Pseudomonas aeruginosa, Citrobacter species and Klebsiella pneumoniae respectively.

Conclusions: Therefore, from the study, it can be concluded that general public needs observe hand hygiene and use of quality disinfection procedures in order to reduce hospital acquired infection.

Keywords: Fomite, Hospital acquired infection, Door handles/knobs, Hand hygiene


Fomite can be described as any non-living object or substance that is capable of carrying infectious organism hence transmitting them from one individual to another.1 There are several factors that affects the contamination rate of fomites such as presence of moisture, frequency of use and general cleanliness.2 It is a well-known fact that Fomites are one of the major source of spread of hospital acquired infection and they provide a possible route for pathogen to pass between patients. Fomites includes among others door handles or knobs of conveniences, showers, toilet seats and faucets, sinks, lockers, chairs, and tables, and these are especially found in public places, hospitals, hotels, restaurants and restrooms.3 However, the most common source of fomites infections in most of the hospitals are door handles or knobs of toilets and bathroom. It is usually believed that fomites are deposited on door handles/knobs while large traffic of users who throng in with their own microbial flora and other organisms have picked them elsewhere while going into the convenience on their way out toilets and bathrooms.4 In general, the risk of disease transmission through fomites is determined by the frequency of site contamination and exposure; level of pathogen excreted by the host; likelihood of transfer of the infectious agent to a susceptible individual; virulence of the organism; immuno-competence of the persons in contact; the practice of control measure such as disinfectant use and personal hygiene.5 Consequently, people who can hardly wash their hands after toilets and bathrooms usage, could result in acquiring community-associated methicillin resistant Staphylococcus aureus (CA-MRSA) and this can result in outbreak especially in high prevalence areas.6 Furthermore, fomites can also serve as bacterial and viral reservoir through aerosolization and direct transfer from hand to fomite surface. Therefore, this study was carried out to determine the level of bacterial contamination of door handles/knobs at Daeyang Luke Hospital toilets and bathrooms. The main aim of the study is to assist in providing scientific information that would have help in hand washing and quality disinfection procedure programmes in Malawi.

Materials and Methods

Samples were obtained between the month of May to August 2016 from toilet door handles/knobs in Medical, Surgical, Paediatric, Postnatal and Antenatal, Labour, Private, OPD, Casualty and staff selected wards at Daeyang Luke Hospital using full aseptic precaution. Samples were collected using the swab-rinse technique of the American Public Health Association as described by Reynolds.5 Door handles/knobs were swabbed with sterile, cotton-tipped applicator (swab stick) moistened with sterile water. The swab samples from door handles/knobs were evenly spread over their entire surfaces of petric dish containing nutrient agar. This was to allow quick recovery of all organisms picked up in the swab. Then, the plates were incubated aerobically for 24 hours at 37˚C.7 Identification and characterisation of bacterial contaminants bacterial isolates were differentiated by macroscopic examination of the colonies. The colonies were differentiated based on size, colour, pigmentation, elevation, surface texture, and margin. Several biochemical tests were also carried out to further identify the various bacterial isolates as described by Barrow and Feltham.8

Results and Discussion

In this research, most of the toilets and bathroom found at Daeyang Luke Hospital were sampled and a total of 442 colonies were observed during the study period. However, 184 colonies were identified representing a 41.6% bacterial contamination level. It was also observed that the level of contamination was less in female medical and surgical ward (10 colonies identified representing a 5.4 percent positive) as compared to the postnatal and antenatal ward which had a total of 33 colonies identified representing a 20.1 percent positive. Furthermore, an average of 79 colonies were observed in the private wards as compared to 27 colonies that were observed in Casualty during the same period (Table 1).

During assessment of toilets, the female medical and surgical ward toilets were more contaminated with 48 colonies being identified as compared to the staff toilets who had less bacterial contaminated with 22 colonies identified. During the same period, private room shower were more contaminated with 44 colonies observed as compared to the staff room showers were less contaminated with 15 colonies observed (Figure 1).

Table 1: Distribution and percentage of bacterial contamination of toilets and bathroom doors handle/knobs at Daeyang Luke Hospital.

Door handle/knobs Total Number of colonies Number positive Percentage positive
Male Medical, Surgical & Paeds Ward 57 27 14.7
Female Medical & Surgical Ward 75 10 5.4
Postnatal and Antenatal 66 37 20.1
Labour Ward 31 23 12.5
Private Ward 79 33 17.9
OPD 70 26 14.1
Casualty 27 17 9.2
Staff 37 11 6.0
TOTAL 442 184 41.6

Table 2: Prevalence and degree of growth of bacteria isolated from contaminated door handles.

Bacteria Number isolated Degree of growth Prevalence
Staphylococcus aureus 26 +++++ 30.6
Klebsiella pneumoniae 7 ++ 8.2
Escherichia coli 21 +++++ 24.7
Enterobacter spp. 4 ++ 4.7
Citrobacter spp. 8 ++ 9.4
Pseudomonas aeruginosa 17 +++ 20
Protea spp. 2 ++ 2.4

Key: + few colony; ++ slightly; +++ more colony; ++++ slightly more; +++++ most

During assessment of the door handle/knobs, it was observed that 44.3% of the door handle/knobs were contaminated. The male toilets had the highest contamination rate with 35.5% as compared to female toilets 19.7% during the period of study. The washroom were less contaminated in general, highest contamination being observed in male washroom 19.4% as compared to female washroom at 9.7%. Private wards general toilets for both male and female were less contaminated at 9.7%, similarly the general washroom at 6.5% (Figure 2).

Figure 1: Bacterial contamination of doors handle/knobs at Daeyang Luke Hospital.

Figure 2: Distribution and percentage of doors handle/knobs assessed and percentage positive at Daeyang Luke Hospital.

Amongst the bacterial contaminant that were isolated and identified, Staphylococcus aureus had the highest prevalence of 30.6%, followed by Escherichia coli (24.7%), Pseudomonas aeruginosa (20.0%), Citrobacter species (9.4%), Klebsiella pneumoniae (8.2%), Enterobacter species (4.7%) and Protea species having the lowest prevalence of 2.4% (Table 2).

Research have shown that an increase in population growth and mobility enhances pathogen transmission and this intensifies the difficulty of interrupting disease spread.9 Other Studies have also shown that most frequently used fomites are most likely to be contaminated and consequently they will generally carry heterotrophic bacterial loads.10 However, this study has observed that most common bacterial contaminants at Daeyang Luke Hospital just like any other hospital in the developing world are S. aureus, E. coli and P. aeruginosa. The study also found that the level of contamination of toilet door handles/knobs were slightly higher than those of washrooms door handles/knobs during the period of study. This variation in the level of contamination of the toilets and bathroom at Daeyang Luke Hospital may be attributed to a larger population usage of toilets as compared to bathrooms. On the other hand, it is a common understanding that fewer people take their baths in bathrooms as compared to those that walk into the toilets to ease themselves.

Furthermore, several studies have observed that proper cleaning of hands decreases some respiratory and gastrointestinal illness while at the same time disinfection of fomites can also decrease surface contamination, hence, interrupting the spread of disease. Some have even suggested that cleaning with a 5,000 ppm chlorine solution is effective in preventing cross-contamination and eliminating norovirus and bacteria from environmental surfaces. Consequently, it can be observed from the study that health workers can play a critical role in helping to reduce hospital acquired infections hence contribute in reduction of high mortality rate in the country through observing hygiene and disinfection intervention.


In conclusion, it can be observed that the fact that these contaminants were at high level, this is of great concern to the management, especially with the growing number of immuno-compromised patients. Thus, immediate intervention needs to be instituted to control those environmental factors which favour the growth and multiplication of microbes. These interventions can also help to reduce mortality rate in the country in general. Consequently, the public needs to observe hand hygiene and use of quality disinfection procedures in order to reduce hospital acquired infection.


Grateful thanks goes to the management and staff of Daeyang University and Daeyang Luke Hospital for providing the facilities for the research work.

Funding: No funding sources

Conflict of interest: None declared


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