A study on Bacterial contamination of Cell phones of Health Care Workers (HCW) at KIMS Hospital, Amalapuram.

*N.Padmaja, PN. Rao.

Abstract:A random 100 samples of cell phones of HCWs workers and Doctors working in various wards, Opds and laboratories, Blood Bank, Causality, ICU of KIMS Hospital were subjected to bacterial analysis by conventional methods to know about the Bacterial contamination of the cell phones from July 2011 to December 2011. The commonest organism isolated from the contaminated cell phone is MRSA - 20%, followed by MSSA - 5%, CONS - 10 %, Micrococcus - 15 % . The obvious observation is none of the doctors’ cell phones are contaminated. In the present study, the contamination rate is compared to the controlled group consisting patients, relatives attending in OPD’s and not working in health care setting.

Introduction:

Hospital infections pose problem of increased mortality and morbidity in patients. The hands of the health care workers act as an important role in transmission of hospital infections. For more than one decade cell phones have become an accessory in day to day life and they have become a part of life. The cell phones of health care workers act as a source of hospital infections. In this connection, it is imperative to study about the contamination of the cell phones which act as a vehicle of transmission of hospital infections.

The causative agents of hospital infections have found a significant way to spread infection in the hospital environment. The present study is aimed at investigating the rate of bacterial contamination of the cell phones of the health care workers in KIMS, Amalapuram. In the present study the contamination rate is compared to the controlled group consisting patients, relatives attending in OPD’s and not working in health care setting.

Materials and Methods:

Random sampling of 100cell phones from HCWs workingin KIMS hospital from July 2011 to December 2011 was carried out. Samples were collected from OPD’s, in patients wards, ICU, Burns ward and Laboratories. A sterile wet swab moistened with sterile demineralised water is used for collecting the sample from the sides of the cell phone and key pad of the cell phone. The swabs were inoculated and streaked on 5 % Sheep blood agar and MacConkey agar (Hi Media, India). The culture plates were aerobically incubated at 370 C for 24 hrs. Isolated organisms were processed according to the colony morphology and Grams stain. The isolates were identified according to the Standard protocol. Tests for identification of Gram positive cocci included catalase, Oxidative/ Fermentative test, aerobic mannitol fermentation and coagulase production, Oxacillin sensitivity of Staphylococcus aureus was carried out by using Oxacillin disk diffusion test.

Out of 100 HCWs, Doctors - 25, Nurses - 25, Laboratory Technicians - 25, House Keeping - 25. Area wise distribution of sample is as follows

OPD’s: Pediatrics-2, Obg & Gyn-3, Medicine-2, Dermatology-2, Pulmonary medicine-2, Surgery-3, ENT-2, Dental-2, Orthopedics-3, Ophthalmology-1, Causality-2, ICU-1.

Wards : Pediatrics-2, Labor room-2, Medicine-3, Gynaecology-4, Blood bank-2, Surgery-2, ENT-2, Dental-2, Orthopedics-2, Ophthalmology-1, Burns ward-2, ICU-1.

Laboratories: 25 from laboratories (Microbiology, Pathology, Biochemistry, Radiology, Blood Bank)Biochemistry-5, Microbiology-6, Pathology-9, Radiology-2, Blood Bank-3.

House Keeping - 25

In the present study, the contamination rate is compared to the controlled group consisting patients, relatives attending in OPD’s and not working in health care setting.

Results:

Bacteriological analysis:Out of 100 samples 50 (50%) were contaminated with bacteria. Out of 50 isolates from cell phones the following bacteria were isolated

Methicillin resistant Staphylococci (MRSA) - 20%.

Methicillin Sensitive Staphylococci (MSSA) - 5%.

Coagulase Negative staphylococci (CONS) 10%

Micrococcus - 15 %.

From the above observations, it is clear that 25 % of the cell phones are contaminated with hospital associated infections that is Staphylococcus aureus. .

The pathogen staphylococcus aureus isolated from cell phones of Doctors is nil. Nurses-18, Laboratory workers-7, House keeping-10.

Area wise distribution of MRSA shows: 8 from HCW working in OPDs, 6 from Laboratories, 5 from wards, 1 from causality.

Controls of 50 samples were taken. Out of 50 control samples, 1 swab from control group showed isolation of Coagulase negative staphylococci.Remaining were sterile. From the above observations it is obvious that Gram negative bacteria and Enterococcus bacteria were not isolated in any of the cell phones and it is found that the hands of HCWs at KIMS hospital setting and the cell phones used by HCWs are colonized with Staphylococci.

Khivsara et al. reported 40% contamination of mobile phones by Staphylococcus and MRSA from HCWs working in a Mangalore Hospital. In a similar study from Turkey hospital, only 9% of mobile phones sampled showed contamination by bacteria associated with nosocomial infections. Similarly, Brady et al. said 14 % of mobile phones showed growth of bacteria known to cause nosocomial infection. Comparing these studies with our study, a higher percentage (50%) of Cell phones sampled was contaminated and 20% HCWs had MRSA growing on their Cell phones.

discussion

The above study reveals cell phones as potential threat in infection control practices and causes health care associated infections. Cell phones carried these bacteria because count of these bacteria increase in high temperatures and our cell phones are ideal breeding sites for these microbes as they are kept in warm in our pockets and hand bags. There are no guidelines for the care, cleaning and restriction of cell phones in our health care system.

So in a country like India, cell phones of HCWs play an important role in transmission of infections to patients which can increase the burden of health care.

CONCLUSION

In conclusion, it can be said that hand hygiene is overlooked and is under emphasized in health care settings. Simple measures like increasing hand hygiene and regular decontamination of cell phones with alcohols, disinfectant wipes may reduce the risk of cross contamination by these devices.

References

  1. Brady RR, Fraser SF, Dunlop MG, Paterson - Brown S, Gibb AP. Bacterial contamination of mobile communication devices in the operative environment. J Hosp Infect 2007; 66:397-8.
  2. Clinical Laboratory Standards Institute, Performance standard for antimicrobial disk susceptibility tests; Approved standards, 2005, vol.25, 8th edn, M02-A8.
  3. Brady RR, Wasson A, Stirling I, McAllister C, Damani NN. Is your phone bugged? The incidence of bacteria known to cause nosocomial infection on healthcare worker’s mobile phones. J Hosp Infect 2006;62:123-5
  4. Karabay O, Kocoglu E, Tahtaci M. The role of mobile phones in the spread of bacteria associated with nosocomial infections. J infect Developing countries 2007; 1:72-3.
  5. Khivsara A, Sushma T, Dhanashree B. Typing of Staphylococcus aureus from mobile phones and clinical samples. Curr Sci 2006;90:910-2.
  6. Gupta V, Datta P, Singla N. Skin and soft tissue infection : Frequency of aerobic bacterial isolates and their antimicrobial susceptibility pattern. J Assoc Physicians Indians India 2008;56:389-90.
  7. Jeske HC, Tiefenthaler W, Hohlrieder M, Hinterberger G, Benzwer A. Bacterial contamination of anesthetist’s hands by personal mobile phone use in the operation theater. Anesthesia 2007;62:904-6.

IDENTIFICATION OF UROVIRULENT MARKERS IN UROPATHOGENIC E.COLI

* N. Padmaja, Anandacharya, P.N.Rao.

Abstract: The present study was conducted in the Department of Microbiology, KIMS, Amalapuram, East Godavari District from August 2011 to January 2012. 50 E.coli strains isolated from urine samples of different clinical entities and 25 feacal isolates were studied for the detection of virulence markers of E.coli. There are 27 UPEC isolates from 50 E.coli & 5 UPEC from 25 controls. Among isolates tested the most common virulent marker is haemolysin 21 (42%), followed by Mannose resistant haemagglutination 16 (32%), cell surface hydrophobicity 13 (26%). In this, there are 14 cases with only one virulence marker, 8 with 2 marker combinations and 15 cases with combination of 3 markers.

Introduction:

UTI is one of the most important causes of morbidity and mortality. E.coli is the most frequent urinary pathogen isolated from 50 % - 90 % of all uncomplicated urinary tract infections. It is now recognized that there are subsets of faecal E.coli, which can colonize periurethral area, enter urinary tract and cause symptomatic diseases. These are currently defined as Uropathogenic E.coli. It has been traditionally described that certain serotypes of E.coli were consistently associated with uropathogenicity and were designated as uropathogenic E.coli. These isolates express chromosomally encoded virulence markers. The virulence factors include different adhesins, haemolysin production, haemagglutination, cell surface hydrophobicity. The present study was designated to determine the urovirulence factors of E.coli isolated from the patients of UTI and to study their antimicrobial susceptibility pattern.

Materials and Methods:

The study was conducted in the Department of Microbiology, KIMS, Amalapuram, East Godawari from August 2011 to January 2012. 50 E.coli strains isolated from urine samples & 25 faecal isolates were studied for 1. α Haemolysin on 5% sheep blood agar. 2. Mannose Resistant Haemagglutination. 3. Cell surface hydrophobicity. 4. Antibiotic susceptibility testing by Kirby - Bauyer disc diffusion method.

Inclusion criteria: Adult patients with UTI attending various clinical departments of KIMS and adult healthy individuals for stool samples are taken.

Samples: 1. Clean catch midstream urine samples from the patients (50). 2. Stool samples of adult healthy individuals (25)

Collection and Culture of sample: Sample is transported to Microbiology lab with in half an hour and processed by 1. Wet film preparation. 2.Culturing on Mac Conkey, Blood agar & CLED agar medium & incubated aerobically at 370 C for 24 hrs. 3. Growth on plates and significant bacterial count. i.e. 105 col / ml and tested for further identification of E.coli by various biochemical reactions. Such E.coli were screened for virulence markers.

Haemolysin: For detecting haemolysin, 5% sheep B.A is used and a zone of lysis around each colony is observed after overnight incubation at 370C, if haemolysin is produced.

Haemagglutination: HA is detected by clumping of erythrocytes by bacterial fimbriae in the presence of D-Mannose. The test was carried out as per the direct bacterial HA test slide method and mannose sensitive and resistant HA tests. HA was considered when it occurred in the presence of 2 % D- Mannose and Mannose sensitive, when it was inhibited by D-Mannose.

Cell surface hydrophobicity: This was done by Salt Aggregation test.Strains are considered hydrophobic, if they are aggregated in concentration of < 1.4 M. Ammonium sulphate.

Antibiotic susceptibility testing: This was performed on all isolates of E.coli by Kirby-bauyer`s disc diffusion method on Muller hinton agar.

Results:

Of the 50 patients, 0 - 15 age group comprised of 11 persons, 16 - 40 age group comprised of 18 persons and > 40 years group comprised of 21 persons. Females (30) are more than male (20) patients. Among various clinical entities, 30 cases presented with lower UTI (60%), 14 cases with asymptomatic bacteriuria (28%) and 6 with pyelonephrities (12%).

Among 50 cases tested 27 (54%) were positive for virulence markers and out of 25 controls, 5 (20%) were positive for virulence markers. Among the isolates tested, the most common virulent marker is haemolysin 21 (42%) followed by Mannose resistant Haemagglutination 16 (32%) and Cell surface hydrophobicity 13 (26%). In control group, the occurrence of haemolysin was 1 (20%), MRHA 3 (60%), CSH 1 (20%). (Note: Percentage calculated as per total 50 isolates). There are 14 cases positive for 1 marker, 8 cases positive for 2 markers and 5 cases positive for 3 markers.

Table showing No. of positive virulence markers - Table I

Composition / No. of Tested / Positive virulence markers / %
Cases / 50 / 27 / 54%
Control / 25 / 5 / 20%

Antibiotic Sensitivity Test:Table II

S.No. / Drug / Sensitivity / % / Resistant / %
1 / Amikacin / 41 / 82% / 6 / 12%
2 / Nitrofurantoin / 39 / 78% / 11 / 22%
3 / Cefotaxime / 36 / 72% / 14 / 28%
4 / Cephalexin / 26 / 52% / 21 / 48%
5 / Co-trimoxazole / 23 / 46% / 17 / 54%
6 / Cefuroxime / 16 / 16% / 34 / 68%
7 / Ampicillin / 13 / 26% / 37 / 74%
8 / Norfloxacin / 10 / 20% / 40 / 80%

41% isolates were sensitive to Amikacin, 78% to Nitrofurantion, 72% sensitive to Cefotaxime, 52% sensitive to Cephalexin, 46% sensitive to Co-trimoxazole. High resistance is seen for Norfloxacin 80% followed by Ampicillin 73%, Cefuroxime 68%. (Note : Percentage drug sensitivity and resistance pattern calculated for total number of 50 strains isolated).

Discussion:

The present study was undertaken to study the virulence factors namely haemolysin production, MRHA and CSH. 50 E.coli isolates from urine of cases with clinically diagnosed UTI are taken as study group and 25 E.coli from faeces of healthy persons as control group. Most of the cases of UTI are from above 40 years age group (21), followed by 16-40 years(18) and 0-15 years (11). The high incidence of UTI was observed above 40 years age group followed by 16-40 years age group. This is because, the elderly patients are likely to be predisposed to conditions like 1. Urinary tract obstruction. 2.Poor bladder emptying 3. Diabetes 4. Prostate enlargement. These factors favour colonization of bacteria and play an important role in UTI.

High incidence of UTI is observed in females (30) than males (20), which is due to 1. short urethra. 2. close proximity of urethra to perianal region.

Regarding AST, most of the isolates are sensitive to Amikacin (82%) and Nitrofurantoin (78%). Where as most of the isolates are resistant to Norflox, Ampicillin, Cefuroxime and Cephalexin. This shows that Aminoglycosides and Nitrofurantoin are useful for most of UTI and high level of resistance indicates the lack of rational drug use.

References:

1. Orskov, F.1984, Genus I.Escherichia castellani and Chalmers 1919. In: Krieg, N.and Holt, J.G. (eds), Bergey`s Manual of systemic bacteriology. London: Williams & Wilkins, 420-3.

2. Smith HW. The haemolysins of Eschericha coli. J. Pathol Bacteriology 1963; 85: 197-211.

3. Kaijser B.Immunology of Escherichia coli. K. Antigen and its relations to UTI. J. Infectious diseases 1973;127:672-677.

4. Quackenbush RL, Falkow S. Relationship between colicin V activity and virulence in E.coli. Infect Immune 1979;24:562-564.

5. Hageberg L, Jodal U, Korhonen Tk, Lidin – Janson G, Lindberg U, Svanborg Eden C. Adhension, haemagglutination and virulence of E.coli causing Urinary track infections. Infect Immune 1981;31:564-570.

6. Lindahl M, Faris A, Wadstrom T, Hjerten S. A new test based on salting out to measure relative surface hydrophobicity of bacterial cells. Biochim Biophys Acta 1981;677:471-6

7. Orskov I, Orskov F; Birch-Andersen A, Kananmori M, Svanborg-Eden C, O, K, H and fimbrial antigens in E.coli serotypes associated with pyelonephritis and cystitis. Scand J Infectious diseases 1982; Suppl 33:18-25.

8. Cavalieri SJ, Bohach GA, Snyder IS. E.coli alpha haemolysin: Characteristics and probable role in pathogenicity. Microbiol Rev 1984;48:326-343.

9. Holmes, B and Gross, R.J. 1990. Coliform bacteria: various other members of the Enterobacteriaceae. In: Parker, M.T. and Collier, L.H. (eds), Topley & Willson`s Principles of bacteriology, Virology and Immunity, 8th edn. London: Edward Arnold, 415-41.

10. L.Siegfried, Marta kmetova, Hana puzova, Maria Molokacova and J.Filika. Virulence-associated factors in E.coli strains isolated from children with urinary tract infections. Journal of Medical Microbiology – Vol.41(1994); 127-132.

11. Johnson J: Microbial virulence determinats and pathogenesis of Urinary tract infection. Infect Dis Clin North Am 2003, 17:261-278.