new the campylobacter control programme in new zealand · 2016. 10. 17. · campylobacteriosis in...

www.mpi.govt.nz • 1 www.mpi.govt.nz

The Campylobacter control

programme in New Zealand

Prof. Steve Hathaway

www.mpi.govt.nz • 2

MPI Campylobacter team

• Steve Hathaway and Peter van der Logt: Science and risk

assessment

• Judi Lee and Sharon Wagener: Standard development

• Gail Duncan: National microbiological database

• Sonja Taege and Catherine Sheerin: Verification

• Sharon Wagener and others: Compliance Response Team

• Craig Thornley: Public health

• Nigel French and Petra Muellner: Source attribution


Campylobacteriosis in New Zealand

(all causes) at start of control programme

0

2,000

4,000

6,000

8,000

10,000

12,000

14,000

16,000

80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 00 01 02 03 04 05 06

Year

No

tifi

ca

tio

ns

0

200

400

600

800

1,000

1,200

Ho

sp

ita

lisa

tio

ns

Notifications

Hospitalisations

Cases

= 380 / 100,000 pop.


Campylobacter Risk Management Strategy

2007 -

• Source attribution studies

• Operational research for effectiveness of different interventions e.g.

freezing, and data gaps e.g. risk factors at farm level

• Develop Biosecurity Manual (growing farms)

• New code of practice for primary and secondary processing

• Establish National Microbiological Database (NMD) and test

different methodologies an monitoring strategies

• Review HACCP-based Risk Management Plans at premises level

• Establish five-year public health goal and reporting

• Develop regulatory performance target and response

• Develop risk assessment models to inform decision-making


Development of the NMD

• 2007: Caecal sampling and carcass sampling;

proposal for mandatory target rather than

mandatory interventions (good performers

should not be penalised!)

• 2008: Performance target with escalating

(regulated) responses

• 2009: Caecal sampling ceases as limited value

• 2013: Revised performance target


Testing programme

• Accredited laboratories

• Trained samplers

• Approved methods

• Regulator can see all premises’ results

• Each premises can only see own results

• Quarterly ranking and reporting


Microbiological performance target

Represents an approximate one log reduction in level of hazard

control cf. 2007 national 80th percentile baseline (4.08 to 3.08 logs)

System accredited and verified by MPI

Moving window, high count limit and quarterly limit

Moving window failure when seven or more out of 45 samples from

three successive processing periods are greater than 3.78 log 10

cfu/carcass

Low throughput premises

Integrated industry and regulator response in case of non-

compliance, with possible escalation to premises closure


Subsequent changes to target

• Moving window failures have effectively managed poor

performers Kept

• Hardly any failures against high count (> 5.88 log10 /

rinsate) or quarterly limits Removed

• Mandatory responses too restrictive:

– amended to be more flexible

– increased reporting

• Compliance Response Team visits very effective Kept


Source attribution


Approaches to attribution

• Analytical epidemiology

• Comparative exposure / risk assessment

• Expert opinion

• Molecular epidemiology

– microbial subtyping e.g. PCR, source tracking, population

genetics and epidemiological modelling add powerful tools

– rMLST (new generation) uses high throughput sequencing of

whole genomes to analyse many more genomic loci


Modelling approach


Massey University EpiLab 2005 -

• Manawatu sentinel

site

• Identify genotypes

common to

particular sources


Campylobacter source attribution


Attribution 2011/12

Attribution 2005/6

???

Campylobacter source attribution

2005 / 2006

2011 / 2012


0

1

2

3

4

5

6

7

00 00 00 00 01 01 01 01 02 02 02 02 03 03 03 03 04 04 04 04 05 05 05 05 06 06 06 06 07 07 07 07 08 08 08 08 09 09 09 09

1 3 5 7 9 11 1 3 5 7 9 11 1 3 5 7 9 11 1 3 5 7 9 11 1 3 5 7 9 11 1 3 5 7 9 11 1 3 5 7 9 11 1 3 5 7 9 11 1 3 5 7 9 11 1 3 5 7 9 11

Urban

Rural no cattle

Rural high cattle

Poultry intervention

2000 2001 2002 2003 2004 2005 2006 2007 2008 2009

Dynamic changes in source attribution


Operational research


Operational research on-farm

• On-farm risk factors for Campylobacter infection of

broilers under New Zealand conditions

• Potential dissemination of Campylobacter by farmers’

overalls in broiler farms

• Effect of caprylic acid on Campylobacter concentration

in broiler caeca


On-farm

Risk factors Voluntary Biosecurity Manual

Environment

Pests

People

Equipment

Cross contamination

during live bird

transport to

processing

Contaminated birds

• Environmental hygiene

• Entry procedures

• Minimise partial depopulations

• Catching procedures

• Crate washing, drying and

sanitation

• Education and commitment of

growers


Live

birds

On-farm biosecurity; Campylobacter cf.

Salmonella

Production

(on farm)

Primary Processing

Secondary Processing

Distribution and Sale

Preparation and

Consumption

Feed

Drinking

water

Environment

Pests

People

Equipment

Minimise Campylobacter on Farm:

- farm biosecurity

Break Salmonella cycle on-farm:

- heat treat feed

- treat drinking water

- controls for grandparents, parents, hatcheries

- strict farm biosecurity

Manage Campylobacter at Primary Processing

-


Code of practice for primary processing


Operational research at primary processing

• Surveys: Broilers, end-of-lay, breeders, turkeys, ducks,

free-range poultry

• Quantification of Campylobacter from internal and

external carcass rinses

• Longitudinal mapping of Campylobacter on carcasses

• Campylobacter recovery from carcasses

• NMD: Investigation of “Not Detected” rinsates

• Chlorinated compounds formed during chlorine wash

of chicken meat

• Immersion chilling: Effect of washing and chlorination


Operational research: Effect of temperature

• Effect of low temperature on Campylobacter on poultry

meat e.g. crust freezing

• Domestic food practices: Refrigerator survey and meat

handling survey

• Domestic food practices: Quantifying the reduction of

Campylobacter on skin-on chicken breasts frozen and

stored up to 10 weeks at -12oC


Primary processing

Post-mortem

examination

Defeathering

Evisceration

Initial chilling

(immersion chillers)

New equipment / equipment set up

Equipment rinse

Post-defeathering rinse (total bird)

Equipment set up (bird size dependent if automated)

Equipment rinses

Multiple bird rinses (total bird)

Pre-chill tank (remove organic matter) Effective immersion chiller operation

•High flow rate (counterflow) •Chlorine control •pH correction •Contact time

Additional post-chill antimicrobial dips

Risk factors Industry actions / Control measures

Personal hygiene

Hand and knife wash stations


Primary processing

• Free-range birds have higher initial levels of

Campylobacter than fully housed birds

• In-line washing and immersion washing decreases

loads by at least one log

• Chlorine immersion decreases loads by at least a

further log

• Higher levels of organic contamination lessens effect

of chlorine (value of pre-chill tank wash)


Operational research: Secondary processing

and consumer

• Effect of secondary processing on

contamination

• Contamination of offal and mechanically

separated meat products

• Contamination on carcasses and portions at

retail

• Campylobacter in drips trapped in leak-proof

packaged retail poultry

• Burden of disease and cost-benefit


Results


Percentage > 3.78 log 10 cfu/carcass

Monthly percentage of samples > 3.78 log10 CFU

0%

5%

10%

15%

20%

25%

30%

35%

2007

4

2007

6

2007

8

2007

10

2007

12

2008

2

2008

4

2008

6

2008

8

2008

10

2008

12

2009

2

2009

4

2009

6

2009

8

2009

10

2009

12

2010

2

2010

4

2010

6

2010

8

2010

10

2010

12

2011

2

2011

4

2011

6

2011

8

2011

10


The premises effect: % positive rinsates

0%

10%

20%

30%

40%

50%

60%

70%

80%

Feb-11 Mar Apr May Jun Jul Aug Sep Oct Nov Dec Jan-12

A

B

C

D

E

F

G

7 ST premises

Campylobacter positive rinsates of different poultry premises


Variable performance at processing steps

0

1

2

3

4

5

6

7

Before evisceration After evisceration After immersion chilling

log

10 C

FU

/ rin

sate

Mean counts (log10 CFU/rinsate) of the outside of the carcasses

Premises A

Premises B

NZ MPI Campylobacter in poultry programme


-

0,10

0,20

0,30

0,40

0,50

0,60

0,70

0

200

400

600

800

1000

1200a

vr.

-07

juil.

-07

oct.-0

7

janv.-

08

avr.

-08

juil.

-08

oct.-0

8

janv.-

09

avr.

-09

juil.

-09

oct.-0

9

janv.-

10

avr.

-10

juil.

-10

oct.-1

0

janv.-

11

avr.

-11

juil.

-11

oct.-1

1

janv.-

12

avr.

-12

juil.

-12

oct.-1

2

janv.-

13

avr.

-13

juil.

-13

oct.-1

3

janv.-

14

Notifications

Variable Association between human cases and % positive

carcasses


Variable Association between human cases and % > 3.78

log 10 cfu/carcass

-

0,05

0,10

0,15

0,20

0,25

0,30

0,35

0

200

400

600

800

1000

1200

avr.

-07

juil.

-07

oct.-0

7

janv.-

08

avr.

-08

juil.

-08

oct.-0

8

janv.-

09

avr.

-09

juil.

-09

oct.-0

9

janv.-

10

avr.

-10

juil.

-10

oct.-1

0

janv.-

11

avr.

-11

juil.

-11

oct.-1

1

janv.-

12

avr.

-12

juil.

-12

oct.-1

2

janv.-

13

avr.

-13

juil.

-13

oct.-1

3

janv.-

14

Notifications


Examples: Compliance Response Team

Issue

Regulatory action

Higher loading (free range), gut breakage, insufficient carcass

washing, sub-optimum management of chemical decontamination

steps

Follow up by VA

Large bird contamination (line speeds), sub-optimum management of

chemical decontamination steps

Follow up by VA

Poor separation between kill and EV rooms, plucker splatter, organic

so needed extra wash steps and use of approved chemical in multiple

decontamination steps

CRT visit

Direction to freeze product,

CRT visit

CRT visit

General hygiene issues, line speed too high, lack of staff, poor

evisceration equipment set up, lack of washing (post pluck, post EV)

/chemical decontamination steps

CRT visit

Direction to freeze product

Direction to add chemical

intervention

General hygiene issues, poor evisceration equipment set up, lack of

control of salting, lack of washing (post pluck, post EV) /chemical

decontamination steps

CRT visit

Direction to freeze product

Insufficient samples, incorrect testing, lack of washing (post pluck,

post EV), poor separation between kill and EV rooms, plucker splatter,

poor control of chemical decontamination steps

CRT visit


Progress against public health goal


Risk management


• Increased stringency could focus on a further

improvement in national performance and/or an

improvement in poorest performing premises

• Target could incorporate tighter acceptance

number, tighter limit etc.

• Risk assessment needed to inform decision but

note that a target does not represent actual

performance of industry

Risk management option: Tightening performance target


• Simple pathway model: Estimates changes in

NMD results with different interventions at the

premises level

• Simple regression model: Estimates human

health risk using NMD data at national level

(noting that it is not possible to directly model the

CPT)

• Alert tool: Simulates alerts and responses for

individual premises using retrospective data and

different inputs to the CPT)

Risk assessment tools


Simple pathway model: Screen shot

Data entry

Changes to routine process

Level immediately after processing step

Unit Distribution

On farm (Caecal prevalence) 50% Percentage

Change

50%

Pre scalding 8.21 CFU log10 \ rinsate Triangular

Additional Change CFU log10 \ rinsate

Scalding and defeathering Effect -1.67 CFU log10 \ rinsate Triangular


6.54

Evisceration Effect -0.18 CFU log10 \ rinsate CDF-Based independent samples

Additional Change 0.00 CFU log10 \ rinsate

6.36

Spin chilling Effect -2.71 CFU log10 \ rinsate CDF-Based independent samples


3.65


Regression model for human illness (1)

NMD % samples

> 3.78 log 10 cfu /

carcass

20%

15%

10%

5%

3%

1%

Campylobacteriosis

notification rate

(per 100,000)

208

187

166

146

135

129

Feb 2011 to

Jan 2012:

8%

April 2007 –

March 2008:

22%

Feb 2007 – Jan

2012: 8%


Regression model for human illness (2)

NMD % positive

samples

70%

60%

30% 25%

20%

Campylobacteriosis

notification rate

(per 100,000)

April 2007 to

Mar 2008:

50%

Feb 2011 to

Jan 2012:

39%

35%

40%

45%

50% 55%

65%

75%

268

236

141 125

109

157

173

188

204 220

252

283

April 2007 –

March 2008:

50%

Feb 2011 – Jan

2012: 39%


Alert modelling tool: screen shot

NMDxyz

0

0.5

1

1.5

2

2.5

3

3.5

2007 5

2007 8

2007 1

2

2008 3

2008 5

2008 8

2008 1

0

2009 1

2009 3

2009 5

2009 8

2009 1

0

2010 1

2010 3

2010 6

2010 8

2010 1

0

2011 1

2011 3

2011 5

Pos_alert

>3.78_alert

Combined

Acceptance number 20 6

MW_Positives MW_>3.78


Revised performance standard: 2013 -

Premises Enumeration

Failure (EF)

Detection

Failure (DF)

Escalation of

Responses

Clearance

ST:

> 1,000,000

birds per

annum

When 7 or more

out of 45

samples are >

3.78 log10CFU/

carcass

When 30 or

more out of 45

samples are ≥

2.30 log10CFU/

carcass)

If the premises

has an EF, a DF

or both it is

counted as one

non-compliant

window.

Responses

escalate

according to the

number of

consecutive non-

compliant

moving windows.

To clear the

non-compliance

a moving

window without

an EF and

without a DF is

required. The

database then

resets to zero to

show that the

premises is

compliant.

VLT:

All others

When 2 or more

out of 9 samples

are > 3.78

log10CFU/

carcass.

When 6 or

more out of 9

samples are ≥

2.30 log10CFU/

carcass.


Campylobacteriosis cases per quarter


-

0,10

0,20

0,30

0,40

0,50

0,60

0,70

0

200

400

600

800

1000

1200a

vr.

-07

juil.

-07

oct.-0

7

janv.-

08

avr.

-08

juil.

-08

oct.-0

8

janv.-

09

avr.

-09

juil.

-09

oct.-0

9

janv.-

10

avr.

-10

juil.

-10

oct.-1

0

janv.-

11

avr.

-11

juil.

-11

oct.-1

1

janv.-

12

avr.

-12

juil.

-12

oct.-1

2

janv.-

13

avr.

-13

juil.

-13

oct.-1

3

janv.-

14

Notifications

Variable Association between human cases and % positive

carcasses


Variable Association between human cases and % > 3.78

log 10 cfu/carcass

-

0,05

0,10

0,15

0,20

0,25

0,30

0,35

0

200

400

600

800

1000

1200

avr.

-07

juil.

-07

oct.-0

7

janv.-

08

avr.

-08

juil.

-08

oct.-0

8

janv.-

09

avr.

-09

juil.

-09

oct.-0

9

janv.-

10

avr.

-10

juil.

-10

oct.-1

0

janv.-

11

avr.

-11

juil.

-11

oct.-1

1

janv.-

12

avr.

-12

juil.

-12

oct.-1

2

janv.-

13

avr.

-13

juil.

-13

oct.-1

3

janv.-

14

Notifications


Changing epidemiology presents challenges


Discussion

• Achieving gains based on biosecurity is a challenge

• New Zealand control programme focuses strongly on

controlling contamination at primary processing by use of

a mandated target rather than mandated interventions

• Working closely with industry to improve situation

• Must be a consequence for poor performance

• Washing of carcasses has demonstrable effect and

chemical decontamination used where necessary

• Further stringency in performance target must be driven

by transparent risk management decisions


Campylobacteriosis: A prime example for a risk-

based approach!

Thank you

new the campylobacter control programme in new zealand · 2016. 10. 17. · campylobacteriosis in...

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