Changes in the epidemiological surveillance of viral hepatitis B and C

In2011, the European Centre for Disease Prevention (ECDC) proposed changing the case definitions for hepatitis B and C, reporting chronic cases of viral hepatitis and remodeling the case-based report to include new variables. At that stage, only cases of acute hepatitis were reported. The objective was to have uniform data from all the countries, data that would be collected from the European system of surveillance (TESSy) in order to make it possible to estimate the prevalence and the changes of epidemiology of viral hepatitis.

 

Proposal: new EU case definition for hepatitis B

Clinical criteria

Not relevant for surveillance purposes

 

Epidemiological criteria

Not relevant for surveillance purposes

 

Laboratory Criteria

  • Positive results of at least one or more of the following tests or combination of tests:
  • IgM Hepatitis B core antibody (anti-HBc IgM)
  • Hepatitis B surface antigen (HBsAg)
  • Hepatitis B e antigen (HBeAg)
  • Hepatitis B nucleic acid in serum (HBV-DNA)

 

Case classification

  • Possible case:NA
  • Probable case: NA
  • Confirmed case:  Any person meeting the laboratory criteria

 

Implementation of hepatitis B case definition with specific variables:

Variable Codes Description
StageHEP

(mandatory)

Acute Detection of IgM antigen specific antibody(anti-HBc IgM

or

Detection of hepatitis surface antigen (HBsAg) and previous negative HBV markers less than 6 months ago

or

Detection of hepatitis B nucleic acid ( HBV-DNA) and previous negative HBV markers less than 6 months ago

or

Any of the above with or without symptoms and signs ( e.g. jaundice, elevated serum aminotransferase levels, fatigue, abdominal pain, loss of appetite, intermittent nausea, vomiting, fever)

  Chronic Detection of HBsAg or HBeAg or HBVDNA

and

No detection of anti-HBc  IgM (negative results)

or

Detection of HBsAg or HBeAg or HBV-DNA on two occasions that are 6 months apart

  UNK Any newly diagnosed case which cannot be classified according the above description of acute or chronic infection.

 

 

Proposal : new EU case definition for hepatitis C

Clinical criteria

Not relevant for surveillance purposes

 

Epidemiological criteria

Not relevant for surveillance purposes

 

Laboratory Criteria

At least one of the following three:

  • Detection of hepatitis C virus  nucleic acid (HCV RNA)
  • Detection of hepatitis C virus core antigen (HCV-core)
  • Hepatitis C virus antibody (anti-HCV Ab) confirmed by a confirmatory (e.g. immunoblot) antibody test in person older than 18 months without the evidence of resolved infection.

 

Case classification

  • Possible case:NA
  • Probable case: NA
  • Confirmed case:  Any person meeting the laboratory criteria

NOTE: The following combination of lab tests shall not be included or reported:

Resolved infection: Detection of hepatitis C virus antibody and no detection of Hepatitis C virus nucleic acid (HCV-core negative result) in serum/plasma.

 

Implementation of hepatitis C case definition with specific variables

Variable Codes Description
StageHEP

(mandatory)

Acute Recent HCV seroconversion (prior negative test for hepatitis C in last 12 months )

or

Detection of hepatitis C virus nucleic acid (HCV RNA) or Hepatitis C virus core antigen (HCV-core) in serum/plasma and no detection of hepatitis C virus antibody(negative result)

  Chronic Detection of hepatitis C virus nucleic acid ( HCR RNA) OR HEPATITIS C core antigen ( HCV-core) in serum/plasma in two samples taken at least 12 months apart
  UNK Any newly diagnosed case which cannot be classified according the above description of acute or chronic infection.

 

 

The set of variables which applies to Hepatitis case-based reporting consists of 34 variables for Hepatitis B and 30 variables for Hepatitis C. These variables can be divided in core-set and disease-specific variables. The variables are designed to allow the distinction between acute and chronic cases through the variable ‘StageHEP’. Further information on cases can be provided through non-mandatory fields.

An aggregated format will also be implemented and will include Gender,Age, Class, StageHEP, Transmission Date used for statistics, Reporting Country and the number of cases. The hierarchy for aggregate reporting is as follows: (1) gender,(2) age class,(3) StageHEP,(4) Transmission.

ECDC strongly recommends case-based reporting.

The variables are described in more detail, including the validation rules, in Annexure 1.

Data sources will need to be appropriately configured for each member state and disease, where these do not already exist. Data sources provide information on the surveillance system, sending the data to ECDC, and are essential in interpreting reported data correctly.

 

Table 1. Overview of enhanced set of variables for Hepatitis surveillance

Type Variable name Mandatory Hepatitis B Hepatitis C
Core-set Record ID Y V V
  Record type Y V V
  Record type version Y V V
  Subject Y V V
  Status Y V V
  Data source Y V V
  Age (years) Y V V
  Gender Y V V
  Outcome   V V
  Date of onset   V V
  Date of diagnosis Y V V
  Date of notification   V V
  Date used for statistics Y V V
  Reporting country Y V V
  Place of residence   V V
  Place of notification   V V
  Classification Y V V
Disease-specific StageHEP Y V V
  Result HBeAg N V NA
  Viral load N V NA
  ALT Level N V V
  Country o fbirth N V V
  Country of nationality N V V
  Imported N V V
  Probable country of infection N V V
  Country of birth parents N V NA
  Transmission N V V
  HCW N V V
  HIV status N V V
  HBV status N NA V
  HCVstatus N V NA
  Prison N V V
  Vaccination status N V NA
  Complications N V V
  Genotype N V V

 

 

Many countries expressed their fears about the reporting of chronic cases as there is already a problem of under-reporting of acute cases and, with an additional burden, the system will collapse.

The Viral Hepatitis Office of HCDCP, in cooperation with the Department of Epidemiological Surveillance and members of the Scientific Committee on Viral Hepatitis of HCDCP, studied the recommendations of the ECDC. Since the new case definitions are based solely on laboratory findings,it was decided to create the laboratory system report of those diseases. The laboratory report form has already been prepared according to the instructions of ECDC and will soon be implemented as a pilot project. The laboratory report will be created electronically and will be sent to HCDCP. We hope that we will soon be able to implement the laboratory report system in all hospitals and private laboratories that perform tests for viral hepatitis B and C.

The report of viral hepatitis through the mandatory report system will be maintained and operate in tandem so that the two systems complement each other.Some of the changes of the mandatory reporting of chronic and acute infectious diseases are related to risk factors, clinical features and laboratory findings.

The success of the epidemiological surveillance will depend on the involvement of clinicians and laboratory physicians and we hope that their cooperation with the HCDCP will provide reliable information, in accordance with the instructions of the ECDC.

Dr G. Nikolopoulou, Head of Viral Hepatitis Office,HCDCP