USE OF ACUTE HEPATITIS USE OF ACUTE HEPATITIS SURVEILLANCE TO SURVEILLANCE TO

EVALUATE PROGRAM FOR EVALUATE PROGRAM FOR VIRAL HEPATITIS VIRAL HEPATITIS

PREVENTION AND CONTROLPREVENTION AND CONTROL

Central Asian Program, DIH, EPO, CDC

Acute Hepatitis Incidence,Acute Hepatitis Incidence,KyrgyzstanKyrgyzstan, 1990-2002, 1990-2002

597,4

475,3394

474,8431,8445,5

278,6

590,3

326,2

201,8

429,9

229,9152,5

597,4

475,3394

474,8431,8445,5

278,6

590,3

326,2

201,8

429,9

229,9152,5

0

100

200

300

400

500

600

700

Years

Inc

ide

nc

e

Weaknesses of the Acute Hepatitis Weaknesses of the Acute Hepatitis Surveillance Used before 2000Surveillance Used before 2000

– Acute hepatitis case definition was not applied

– Cases were not serologically tested for specific markers of acute hepatitis A,B,C and D

– Epidemiological data collection procedure Epidemiological data collection procedure and analysis methodology were not and analysis methodology were not standardizedstandardized

Sentinel Surveillance IntroductionSentinel Surveillance Introduction ((goalsgoals))

• To provide reliable etiological diagnostics of acute viral hepatitis on bases of representative sample

• To define risk groups and risk factors for acute hepatitis

• To use surveillance data for design, monitoring and evaluation of programs for viral hepatitis control and prevention

• To provide database for epidemiological studies

Sentinel Surveillance Introduction Sentinel Surveillance Introduction ((stagesstages 1) 1)

• National Reference Laboratory was established; standard laboratory procedures and quality assurance were provided

• External Quality Assessment of the accuracy of Reference laboratory results was conducted in CDC, Atlanta

• Corresponding Ministry of Health orders were issued

• Sentinel Sites were organized in three regions: Bishkek, Naryn and Jalal-Abad

Sentinel Surveillance Introduction Sentinel Surveillance Introduction ((stagesstages 22))

• The structure and procedure of sentinel surveillance were developed, including:– sample size and sampling design– acute hepatitis case definition– algorism of laboratory testing– acute hepatitis case classification– standard questionnaire for epidemiological data collection– blood samples collection and transportation

• 4 trainings have been conducted for the sentinel sites personnel (laboratory workers, physicians, epidemiologists, nurses) on sentinel surveillance structure and operating, data quality assurance

Acute Hepatitis Case

Infectious Hospital(physician, nurse)

- confirmation of correspondence to case definition- filling in and marking of the questionnaire - blood sample collection and marking - transportation of samples and questionnaires to the State Sanitation and Epidemiological Surveillance Center

State Sanitary and Epidemiological Surveillance Center

(epidemiologist, laboratory worker)

- serum separation - transportation of samples and questionnaires to the Reference Laboratory

Reference Laboratory(epidemiologist, laboratory worker)

- laboratory testing- data entering- data analysis and report preparation

Ministry of Health

State Department of Sanitation and Epidemiological

Surveillance

Regional health authorities and State Sanitation and Epidemiological Surveillance Centers

report report report

Algorithm of Laboratory TestingAlgorithm of Laboratory Testing

Blood sample

HBsAgIgM

anti-HBcIgM

anti-HAVTotal

anti-HCV

Anti-HDV

+

GNP/capitaGNP/capita ((USDUSD) 1994-2000) 1994-2000

Country/Years 1994 2000 (estimate for 2002)

GNP increase

Kazakhstan 721 1230 70.6%

Kyrgyzstan 275.3 286 4%

Tajikistan 159.1 159,8 0.4%

Turkmenistan 517 552,5 6.9%

Uzbekistan 255.4 264,3 3.4%European Bank for Reconstruction and Development. Transition Report Update, May 2002.

Aims: Aims:

• To evaluate parenteral hepatitis risk factors

• To assess an impact of universal newborn Hepatitis B immunization program

Materials and MethodsMaterials and Methods ((11))

• Study design: matched case control study (1 case + 2 controls matched by age, sex and place of residence)

• Cases: acute hepatitis B, C and D cases (parenteral hepatitis), 2000-2003

• Controls: acute hepatitis A cases, 2000-2003 • N = 214 case-control sets• EPI INFO matched case-control analysis

followed by conditional logistic regression

Risk Factors Risk Factors ((6 months prior to the onset of disease6 months prior to the onset of disease))

• Blood transfusion• Surgery• Injections in hospital• Injections in polyclinic• Blood samples collection in polyclinic• Visit to surgeon, dentist, urologist, gynecologist• Blood donation• Multiple sexual partners• STD

Risk Factors of Parenteral Risk Factors of Parenteral HepatitisHepatitis ( (monovariate analysismonovariate analysis))

Факторы риска Frequency

(N=642)

OR Confidence interval СI0.95

P value

Cases Controls

Blood transfusion 5.6% 0.2% 24.0 [3.1; 184.6] <0.001

Injections in hospital

5.6% 0.9% 7.6 [2.1; 27.6] <0.001

Injections in policlinic

22.0% 7.2% 3.5 [2.1; 5.8] <0.001

Surgeon 7.0% 1.6% 4.8 [1.9; 12.6] <0.001

Multiple sexual partners

4.7% 1.4% 8.7 [1.8; 41.9] <0.05

Risk Factors of Parenteral Risk Factors of Parenteral HepatitisHepatitis(2)(2)

Risk factors βίOR=e

Confidence interval СI0.95

P value

Blood transfusion 11.4 [1.3; 99.7] <0,05

Injections in hospital

3.2 [2.0; 5.9] <0,001

Injections in policlinic

5.7 [1.1; 15.9] <0,001

Surgeon 1.1 [0.2; 5.4] >0,05

Multiple sexual partners

5.2 [1.5; 17.6] <0,01

ConclusionConclusion

• Risk of parenterally transmitted viral hepatitis remains significant in health facilities. The system of blood and injection safety should be improved

• The system of health communication and training to improve understanding of natural Hep B transmission mechanisms and prevention measures should be strengthened (+HIV)

Hepatitis B Immunization Program Hepatitis B Immunization Program in Kyrgyzstanin Kyrgyzstan

• Introduced in April 1999

• High immunization coverage – > 95%

• 23 cases of acute HB among fully immunized children registered by routine surveillance

Surveillance

Routine(syndrome based)

Sentinel(laboratory based)

High sensitivity

(95%)

Low specificity

(17%)

Lowsensitivity

(7%)

High specificity

(87%)

Materials and MethodsMaterials and Methods (2) (2)

• Comparison of acute hepatitis B incidence rates among vaccinated and unvaccinated children born in sentinel sites between 2000 and 2003

• Analyses of acute hepatitis B incidence among children under 5 years of age in sentinel sites for the period 2000 to 2003

– Hepatitis B cases: acute hepatitis sentinel surveillance database

– Vaccination status of acute hepatitis B cases: primary health facility immunization records

– Number of children in age groups and vaccination status of non-infected children: official statistical data of the Ministry of Health

Acute Hepatitis B Cases Among Acute Hepatitis B Cases Among Children Under 4,Children Under 4,

Sentinel Surveillance,Sentinel Surveillance, 2000-2003 2000-2003Sentinel sites Number of

children under 4

Children born after April 1999

Children fully immunized

Bishkek 15 4 0Dzalal-Abad 33 9 2Naryn 5 1 0Total: 53 14 2

Incidence rates among vaccinated and Incidence rates among vaccinated and unvaccinated children, Bishkek, Naryn, Jalalabat unvaccinated children, Bishkek, Naryn, Jalalabat , ,

2000-2003 2000-2003

Number of children born in 2000-2003 37 784

Number of fully vaccinated children 37 112

Number unvaccinated children 672

Number of acute HB cases among vaccinated children

2

Number of acute HB cases among unvaccinated children

12

Incidence rate among vaccinated children 2.9 per 100,000 child-years

Incidence rate among unvaccinated children 760.0 per 100,000 child-years

Acute Hepatitis Incidence Among Acute Hepatitis Incidence Among children under 5, 2000-2003children under 5, 2000-2003

47,4

18,8

75,1

26

46

66

86

0

5

10

15

20

25

30

35

40

45

50

2000 2001 2002 2003

%

0

10

20

30

40

50

60

70

80

90

100

Mo

rbid

ity

rati

o %

000

VHB morbidity rate VHB immunization coverage

Conclusions Conclusions (1)(1)

• AHSS allows effective MONITORING of immunization program in sentinel sites, providing the ability to: – carry out epidemiological investigation of every

case of acute viral Hepatitis B– identify and quickly respond to immunization

program errors

ConclusionsConclusions (2) (2)

KAHSS provides:

• the ability to EVALUATE the impact of an immunization program

• an advocacy tool to support the necessity of sustainable immunization programs

Study LimitationsStudy Limitations

• Evaluation of risk factors:– Use of acute hepatitis A cases as controls; – Aggregation of acute hepatitis B, C and D

cases into one group of parenteral hepatitis

• Evaluation of Immunization program:– Use of official statistical data to define the

size of target age groups and vaccinated and unvaccinated children

AcknowledgementsAcknowledgements

• The Ministry of Health of the Kyrgyz Republic

• Republican Center for Viral Hepatitis Prevention

• State Department of Sanitation and Epidemiological Surveillance

• Republican Center for Immunization