“ Detection of Staphylococcal carriage state among Nursing Staff”
2nd M.sc., 4th semester
commenest ubiquitous bacteria
- leading pathogen causing nosocomial & also community acquired infections.
Indiscriminate use of antibiotics - Drug resistance
Penicillin - Very effective medication to treat Staphylococcal infections
Penicillin resistance - Penicillinase inactivated the antibiotic
Discovery of new antibiotic Methicillin in 1959
Methicillin resistance Staphylococcus aureus(MRSA) - 'Superbug'
Mechanism of drug resistance - alteration in the binding sites and production of enzymes
Methicillin resistance was mediated by penicillin binding protein[PBP2a], Encoded by the mec A gene situated on the mobile genetic element, Staphyloccal cassette chromosome mec (SCC mec)
Hand carriage of Staphylococcus aureus in health care workers is the commonest mode of transmission to patients during cleaning of wounds.
Healthy carrier state of Staphylococcus aureus - A major problem
To detect the MRSA carriage rate among the Nursing staff.
To study the antibiogram of the Staphylococcal isolates.
Aims and objectives
Swab used to collect sample
Collection of finger and throat swab
Culturing on Mannitol salt agar medium
Identification of S.aureus on MSA
Tube Coagulase test
Oxacillin resistance salt screening agar test
Antibiotic Susceptibility Test
SEX AND WARD DISTRIBUTION OF NURSING STAFF
Out of110 nursing staffs, 18 were males & 92 were females. Majority ofthe nursing staff were from Dialysis unit & Major OT.
STAPHYLOCOCCAL GROWTH FROM THROAT SWAB
Among110 nursing staff screened,14 isolates were isolated from throat swabsof nursing staff, of the 14 isolates, 11 isolates yielded the growth ofcoagulase positive staphylococci [COPS]& 3 isolates yielded thegrowth of coagulase negative staphylococci [CONS] . out of 11 isolates,significant growth of coagulase positive staphylococci was observedamong 5 nursing staff of Dialysis unit
Outof 110 nursing staff screened,14 isolates were isolated from fingerswabs of nursing staff, of the 14 isolates, 3 isolates yielded thegrowth of coagulase positive staphylococci [COPS]& 11 isolatesyielded the growth of coagulase negative staphylococci [CONS]. Amongthe 3 isolates all the 3 were from Dialysis unit & significantgrowth of coagulase negative staphylococci was observed among 4 nursingstaff of Dialysis unit & Major OT
Pink coloured coagulase negative Staphylococcal colonies
Yellow coloured Staphylococcus aureus colonies
DETECTION OF OXACILLIN RESISTANCE BY USING OXACILLIN RESISTANT SCREENING AGAR IN THROAT SWAB
Among110 nursing staff screened, 11 isolates yielded the growth of coagulasepositive staphylococci in the throat swabs& all the 11 isolateswere carriers of Methicillin Sensitive Staphylococcus aureus[MSSA] & none of them carried Methicillin Resistant Staphylococcus aureus [MRSA]
3 isolates yielded the growth of coagulase negative staphylococci . Ofthe 3 isolates 1 was carrier of Methicillin Sensitive- coagulasenegative Staphylococcus aureus [MS-CONS] & 2 of them carriedMethicillin Resistant- coagulase negative Staphylococcus aureus[MR-CONS]
DETECTION OF OXACILLIN RESISTANCE BY USING OXACILLIN RESISTANT SCREENING AGAR IN FINGER SWAB
Outof 110 nursing staff screened, 3 isolates yielded the growth ofcoagulase positive staphylococci in the finger swabs& all the 3isolates were carriers of Methicillin Sensitive Staphylococcus aureus[MSSA] & none of them carried Methicillin Resistant Staphylococcus aureus [MRSA]
11 isolates yielded the growth of coagulase negative staphylococci . Ofthe 11 isolates 8 were carriers of Methicillin Sensitive- coagulasenegative Staphylococcus aureus [MS-CONS] & 3 of them carriedMethicillin Resistant- coagulase negative Staphylococcus aureus[MR-CONS]
COMPARISION OF DISC DIFFUSION WITH ORSA METHOD FOR DETECTION OF MRSA IN THROAT SWAB
Among 8 coagulase positive S
taphylococci, 7 of them were sensitive by both disc diffusion & ORSA methods.Only 1 strain showed resistance to oxacillin by disc diffusion method ,but on ORSA none of the strain was resistant
COMPARISION OF DISC DIFFUSION WITH ORSA METHOD FOR DETECTION OF MRSA IN FINGER SWAB
Among 3coagulase positive staphylococci , all the 3 strains were sensitive byboth disc diffusion & ORSA methods & none of the strains wereresistant to oxacillin by both methods.
1. Result plate
2. standard plate
1. Oxacillin Resistant Salt Screening agar plate showing negative result for Methicillin Resistant Staphylococcus aureus.
2. Oxacillin Resistant Salt Screening agar plate showing Positive result for Methicillin Resistant Staphylococcus aureus.
Of the 110 participants, from 12 wards 18 were males & 92 were females. Of 110 nursing staffs screened ,the Staphylococcal
carriage rate in both throat & on hand was 12.7% .None of them werecarriers of MRSA which was identified on the basis of disc diffusion& Oxacillin Screen Agar test. All isolates were sensitive toVancomycin.
A considerably low Staphylococcal carriage rate noticed in our study , lowers the risk of carriage of MRSA strain also.
throat & hand carriers nurses should be identified & trained topractice infection control measures. Nurses who acquire MRSA inhospital also transmit the organism to their hosehold eventuallyspreading such Nosocomially acquired Multidrug Resistant bacteria inthe community , therefore, such carriage study should be conducted at aregular basis in all health sectors followed by the treatment of theidentified carriers.
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