Scottish MRSA Ref' Lab'

1
Scottish MRSA Ref. Lab.
2
SMRSARL SCIEH Referrals
3
Scottish MRSA Ref Lab

• Scottish PHLS covers England Wales
• MRSA remit also includes other MSSA CNS
• Ref Lab Specialists techniques National
  coverage

4
Services Provided

• MRSA status confirmation

• Epidemiological Typing
• Phenotypic
• Genotypic

• Other Services

• National MRSA Database

• Research Development

5
MRSA Status Confirmation

• Various phenotypic tests

• PCR Multiplex
• mecA gene
• nuc gene

6
Other Services

• Vancomycin intermediate resistant MRSA (VISA)

Scottish MRSA Reference Laboratory
7
PCR Toxin Detection
EMRSA-16p
M
tst
nuc
sec
seb
sea
Scottish MRSA Reference Laboratory
8
Epidemiological Typing
9
Epidemiological Typing - Phenotypic Methods
Biotyping
Phage Typing
10
Epidemiological Typing - Molecular Methods
11
SMRSARL Remit

• to provide laboratory backup
• for the control / eradication
• of MRSA
• in Scottish hospitals

12
MRSA Headline News
1. Numbers
2. MRSA Evolution
13
MRSA in Scotland Blood Isolates (1986 - 2001)
Based on SCIEH Reports
14
Prevalence of MRSA in Scotland (Blood Cultures)
42 MRSA
33 MRSA
40 MRSA
40 MRSA
(1-3 Quarters Data Only)
Data from Surveillance Report in SCIEH Weekly
Report
15
World-Wide Prevalence of MRSA
Europe (24) (range 1-60)
Canada (2)
Denmark/ Norway (lt1)
UK (42)
Japan (74)
USA (36)
China (39)
Taiwan (61)
Hong Kong (80)
Latin America (29)
Singapore (63)
Africa Nigeria (21) Zimbabwe (43) South Africa
(49)
Australia (30)
India (34)
16
EARSS (European Antimicrobial Resistance
Surveillance System)
17
EARSS (European Antimicrobial Resistance
Surveillance System)
18
MRSA/MSSA Bacteraemia (Scotland)
Data from Surveillance Report in SCIEH Weekly
Report 13 March 2001 Vol 35 (No 2001/10) (Figures
used are estimates from chart in SCIEH report)
19
MRSA Clones/Strains in Scotland
69
73
28
24
23
20
16
20
Distribution of MRSA Clones in Scotland

• EMRSA-15 more prevalent in East

• EMRSA-16 more prevalent in West

21
Resistance Patterns of MRSA in Scotland -Table 1
Resistant
Sensitive
22
Resistance Patterns of MRSA in Scotland -Table (2)
Resistant
Sensitive
23
World-Wide MRSA Clones

• Super Epidemic (International) Clones
• Iberian
• Archaic/Paediatric
• Berlin MRSA
• VISA clone
• New York Clone
• EMRSA-1
• EMRSA-15
• EMRSA-16
• Brazilian

• Epidemic (National) Clones
• EMRSA-3
• Mexican
• North German
• Canadian MRSA-1

• SMRSA-99 (CC8)

• SMRSA-105

• SMRSA-111 (ST45)

• SMRSA-105 (ST5)

• SMRSA-105

24
Multi-Locus Sequence Typing

• 7 House keeping genes

• 500bp each ( 3500bp)

CTATGTTTAT GTGCGACTTT ATTGAACTTT TATTATTGTG
ACGGGTTTGA 50 ATCCAAGTGA GATAAAAAAA
GTTATCATCG GTAACGTACT ACAAGCAGGA 100
CAAGGACAAA ATCCAGCACG AATTGCTGCT ATGAAAGGTG
GCTTACCAGA 150 GACAGTACCT GCATTTACAG
TGAATAAAGT ATGTGGTTCT GGGTTAAAGT 200
CGATTCAATT AGCATATCAA ACAAAAAAAA AAGGTGAAAA
TGACATCGTG 250 CTAGCTGGCG GTATGGAGAA
TATGTCTCAA TCACCAATGC TTGTCAACAA 300
CAGTCGCTTT GGTTTTAAAA TGGGACATCA ATCAATGGTT
GATAGCATGG 350 TATATGATGG TTTAACAGAT
GTATTTAATC AATATCATAT GGGTATTACT 400
GCTGAAAATT TAGTAG
25
Origin of MRSA
26
MRSA Evolution
SMRSA-105
EMRSA-16
EMRSA-15
SMRSA-111
27
MRSA Genomics
28
mec complex (class B)
ccr complex (type 1)
orfX
TypeI SCCmec (34kb)
?mecR1
ccrA1
?ccrB1
R-I
mecA
?
?
?IS1272
IS431mec
mec complex (class A)
TypeII SCCmec (53kb)
ccr complex (type 2)
orfX
pUB110
Tn554
?
ccrB2
?
ccrA2
IS431mec
mecI
mecR1
IS431mec
Type III SCCmec (67kb)
mec complex (class A)
?ccr complex
ccr complex (type3)
orfX
pT181
mer
?Tn554
ccrA3
mecI
mecA
Tn554
mecR1
ccrB3
IS431mec
IS431
IS431
Mec complex (class B)
Type IV SCCmec (24kb)
ccr complex (type2)
orfX
?
?
mecA
IS431mec
?IS 1272
?mecR1
29
MRSA Clones Proposed Nomenclature
Resistance Character (MRSA/MSSA/GISA)
SCCmec Type
MLST Type
ST22-MRSA-IV
30
SCCmec PCR Assay
31
SCCmec Prevalence in UK
32
SCCmec Type IV Mobile mec

• In many MRSA Clones

• No in-vitro transfer
• demonstrated to date

• Commonest SCCmec

• CNS SCCmec type

Gene spread
33
Community MRSA
34
Community MRSA Characteristics -1
1. Non-multi-resistant
2. Fast growth rate
4. Different from Hospital MRSA clones

• 5. Absence of usual risk factors for MRSA
  acquisition
• Antibiotic therapy
• Hospital stay

35
Community MRSA Characteristics -2
6. Association with Children

• 4 deaths (7-16 year olds)

7. Panton-Valetine leucocidin toxin

• necrotising pneumonia

8. Associated with Skin lesions (boils/abscess)
9. Family transmission / Eradication difficult
36
C-MRSA in Scotland
1. Screened 40 Scottish MRSA clones

• 2. Three MRSA clones PVL positive
• SMRSA-116
• SMRSA-124
• SMRSA-153

• 3. One MSSA PVL positive
• E16 lineage
• Family history of boils and abscess

37
Vancomycin-Resistant MRSA

• VanA gene enterococcal DNA element

• 1st and 2nd VRSA different clones ?

• VRSA selective environment is here !!!