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Pertussis SurveillanceExamples from Europe

Johannes G. Liese

Pediatric Infectious Diseases and ImmunologyUniversity Childrens Hospital

Julius-Maximilians-University, Würzburg, Germany

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Pertussis Surveillance

Switzerland

Austria

Sweden

Germany

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Pertussis Surveillance

Switzerland

Austria

Sweden

Germany

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SENTINELLA Network in Switzerland

Established in 1991

Approx. 200 private practice physicians (GPs, pediatricians, internists), 3% of total, representative

Weekly reporting of suspected cases to Swiss PH Office

Free PCR testing offered since 1994

Case definitions:cough lasting for at least 14 days with either an epidemiological link to another pertussis case (epidemic case) or with 1 of the following symptoms: paroxysmal cough, wheezing on inspiration, or post-tussive vomiting (sporadic case)

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SENTINELLA Network in Switzerland

From July 1991 to December 2006, a total of 4992 cases of pertussis were reported

Since 1994, 80.4% (3723 of 4629) of all reported cases have been tested with PCR

904 (24.3%) of these 3723 tested cases were positive for B. pertussis by PCR

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SENTINELLA Network in Switzerland

0

0.05

0.1

0.15

0.2

0.25

1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006Year

Cas

es p

er 1

00 c

onsu

ltatio

ns

0

50

100

150

200

250

Num

ber o

f PC

R p

ositi

ve (b

lack

) and

PC

R n

egat

ive

(gre

y) c

ases

manuscript in preparation

8

5664717580105

180185165

280

370

70 70

0

50

100

150

200

250

300

350

400

1992 1993 1994 1995 1996 1997 1998 2000 2001 2002 2003 2004 2005

Per 100,000

Prospective studies:Prospective studies:180180--550550

Yearly Estimated Pertussis Incidence in Switzerland (Sentinella 1992-2005)

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Pertussis Epidemiology in Switzerland

0

5

10

15

20

25

0

1-5

6-10

11-1

5

16-2

0

21-2

5

26-3

0

31-3

5

36-4

0

41-4

5

46-5

0

51-6

0

61-7

0

>70

Age category (years)

Prop

ortio

n of

tota

l num

ber o

f cas

es

repo

rted

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g th

e re

spec

tive

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perio

d (%

)

1991-1999 2000-2006

manuscript in preparation

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SENTINELLA Network in SwitzerlandConclusions

A valuable tool to monitor pertussis disease activity in Switzerland

Further analyses are currently in progress

Probably limited utility by “observer bias” (only “typical cases” reported)

Supported by ongoing pediatric surveillance of hospitalized cases (since 2006)

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Pertussis Surveillance

Switzerland

Austria

Sweden

Germany

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Hospital-based active surveillance of childhood pertussis in Austria from 1996 to 2003

8-year prospective active surveillance of B. pertussis infection including all 44 nationwide paediatric departments

Immunisation schedule: 3 doses at 3-4-5 months followed by a single booster vaccination in the second year of age

Vaccines used1996 to 1997: wcP vaccine1998 to 1999: wcP and acP vaccine 2000 to 2003: aP only (Tetra-, Penta-,Hexavalent)

Rendi-Wagner P et al.- Vaccine. 2006;24(33-34):5960-5

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Pertussis hospitalisation incidence and vaccine coverage in Austria from 1996 to 2003

Rendi-Wagner P et al.- Vaccine. 2006;24(33-34):5960-5

wcP vaccine wcP and acP vaccine acP only

79% 86% 92%

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Pertussis Surveillance

Switzerland

Austria

Sweden

Germany

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Pertussis in Sweden – Data from long-term surveillance 1997-2007

To document long-term control of pertussis incidence using aP vaccines after re-introduction of pertussis vaccination in Sweden

To collect background data for timing of later booster dose(s)

Data from the 10-year Report (1 Oct 1997 – 31 Dec 2007)

Swedish National Surveillance System /Swedish Institute for Infectious Disease Control

CIRC.09/02/PPMH/204

1. Olin P, Hallander HO. Euro Surveill. 1999. 2. Gustafsson L, Carlsson RM. Ten Year Report 1997-2007. 3. Carlsson RM, Trollfors B. Vaccine 2009

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Enhanced prospective surveillance of pertussis disease

NATIONAL COHORT: All children in Sweden* born since January 1, 1996 [1]

ENHANCED SURVEILLANCE OF PERTUSSIS [1]Cases identified in national register of reportsConfirmation of B.pertussis by culture- or PCR, regardless symptoms Detailed documentation:

• vaccination history• clinical course• total duration of cough• presence of complications• hospital admissions• length of hospital stay• antibiotic treatment

* Except cohort from Göteborg area

Gustafsson L, Carlsson RM. Ten Year Report 1997-2007

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Pertussis cases reported in Sweden (1986-2007)

1979 – withdrawal of wcP vaccine in Sweden due to safety concerns [1] 1996 – introduction of aP vaccines, switching from DT to DTaP at 3-5-

12m; 3-dose coverage reached 98-99% within a year. [1]Gustafsson L, Carlsson RM. Ten Year Report 1997-2007

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Age-specific incidence of pertussis in Swedenbefore and after introduction of acP vaccines

Birth cohorts after introduction of acP had a much lower age-specific incidence of pertussis than had the corresponding age-groups before introduction of acP

The modest increase in pertussis incidence approximately 5 years after the aP doses were administered could suggest waning of protection.

Gustafsson L, Carlsson RM. Ten Year Report 1997-2007

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Sweden: Incidence of pertussis episodes, hospitalisation, and complications

Higher risk of pertussis-related hospital admissions/complications Among infants who are unvaccinated before 3mOr with only 1 dose of aP from 3 to <5m

Gustafsson L, Carlsson RM. Ten Year Report 1997-2007

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Sweden: Incidence of pertussis in National compared to DT-2aP-Hib-Polio cohort: 1997-2007

The reduced incidence rates of pertussis seen in the DT-2aP-Hib-Polio Vaccine cohort are similar to the rates observed in the national cohort. [1,3]

Gustafsson L, Carlsson RM. Ten Year Report 1997-2007

DT-2aP-Hib-Polio Vaccine

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Sweden: Summary of experience with aP combined vaccines

The introduction of acP vaccines has reduced the incidence of pertussis in Sweden [1]

Before vaccine reintroduction = 121-150 per 100,000 (1993-1995)After acP introduction = 6-16 per 100,000 (2001-2007)

PentaximTM is effective in preventing pertussis in infants and children. [1,3]

The age-specific incidence rates of pertussis seen in the Pentaxim™ cohort are similar to the rates observed in the national cohort

[1] Gustafsson L, Carlsson RM. TEN YEAR REPORT – Pertussis surveillance in Sweden progress report October 1, 1997 – December 31, 2007. [3] Gustafsson L, Carlsson RM. Appendix 2 to Ten-year Report;October 1, 1997 until December 31, 2007

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Pertussis Surveillance

Switzerland

Austria

Sweden

Germany

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Incidence of notified pertussis cases 1947-2007 (Germany: FWG/FEG)

Hellenbrand W et al. BMC Infectious Diseases 2009

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Incidence of Pertussis East Germany 1983 – 2005

19900,4

200020,4

19801,0

12,3

200639,3

200528,3

1980 1990 2000

C. Huelße / Robert-Koch Institut / Epidemiologisches Bulletin Nr. 23 – 2005

Hellenbrand W et al. BMC Infectious Diseases 2009

20070

5

10

15

20

25

30

35

40

45

Pert

ussi

s ca

ses

/ 100

,000

inha

bita

nts

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Confirmation of cases 2002-2007

Laboratory confirmed: 93.8%

Epidemiological link: 1.9%

Clinical case only: 4.4%

Hellenbrand W et al. BMC Infectious Diseases 2009

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Laboratory confirmation of cases 2002-2007

Culture:1.0%

PCR:9.8%

Increase in antibodies:26.9%

Single high titre:56.2%

Hellenbrand W et al. BMC Infectious Diseases 2009

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Age distribution of notified cases in former East Germany

Hellenbrand W et al. BMC Infectious Diseases 2009

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Age distribution of Pertussis East Germany 2001 – 2006

10%

3%

24%

13%

22%

25%

12%

0 - <1 1 - <5 5 - <15 15 - <25 25 - <45 45 - <65 >65 Age

C. Huelße / Robert-Koch Institut / Epidemiologisches Bulletin Nr. 23 – 2005

60%

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Notified cases in former East German states: Saxony (Fig. B) introduced pre-school booster in 1998

Saxonywith preschool booster

Brandenburg, Mecklenburg WesternPomerania, Saxony Anhalt and Thuringia:

no preschool booster

Hellenbrand W et al. BMC Infectious Diseases 2009

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Hospitalized cases in former East Germany (FEG) and former West Germany (FWG)

Hellenbrand W et al. BMC Infectious Diseases 2009

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Vaccination Strategies in Germany Vaccination advisory board (STIKO)

1976 to 1991No pertussis vaccinationEndemic pertussis

1994 Rapid uptake and high coverage after licensure of aP-vaccines

1995-1999pertussis incidence

observed in adolescents

1999-2003pertussis incidence in

infants 2000-2006

pertussis incidence in school age children

pertussis incidence in adults

19914 doses pertussis vaccine schedule in all infants and toddlers

2000all adolescents 9-17 yrs (1 dose)health and childcare workers

(every 10 years)2004

Cocoon strategy2006

Preschool booster 2009

First adult dose recommended

STIKO Robert-Koch-Institut Epidemiologisches Bulletin 2000 - 2009

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Vaccination Calendar (STIKO) for Infants, Children, and Adolescents in Germany - 2009

Age in months Age in years

Vaccine Birth 2 3 4 11-14 15-23 5-6 9-17

DTaP 1. 2. 3. 4. TdaP B B

Hib 1. 2. 3. 4.

IPV 1. 2. 3. 4. B

HB (1.) 1. 2. 3. 4. P

Pneumococc. 1. 2. 3. 4.

Meningococc. 1.

MMR 1. 2.

Varicella 1. (2.) P

+ 1 dose aP in contacts of neonates (Cocoon strategy)

STIKO Robert-Koch-Institut Epidemiologisches Bulletin 2000 - 2009

+ 1 dose aP ten year after adolescent dose

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Pertussis SurveillanceExamples from Europe

Switzerland Surveilance in a high endemic country

Austria Effectiveness of acP program against pertussis hospitalization

SwedenEffectiveness of 2- and 3-component acP vaccine in reducing the burden of pertussis disease

GermanyDevelopment of vaccine recommendations following changes in epidemiology

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