Chronic Hepatitis B Surveillance in Santa Clara County Sara H. Cody, MD Deputy Health Officer An evaluation to understand meaning and usefulness of surveillance data

© 2012 Santa Clara County Public Health Department The Public Health Department is owned and operated by the County of Santa Clara Background and Impetus Chronic Hepatitis B is a high volume disease Majority of reports are from commercial labs Fall 2011: several concerning reports Quest reporting “screening” rather than “confirmatory” results Lab Corp reporting out of state pts

Garbage in, garbage out?

© 2012 Santa Clara County Public Health Department The Public Health Department is owned and operated by the County of Santa Clara Hepatitis B data flow Hospital or Commercial Lab Provider Laboratory Report CMR SCCPHD via fax Clerks check faxes, date stamp Verify county of residence SCC resident OOJ IgM Non-IgM PHN review, sort into Probable, confirmed or perinatal Clerk Data entry into CalREDIE 4 Compiled all data rec’d during 1 st quarter of 2012 (Jan-Mar )

© 2012 Santa Clara County Public Health Department The Public Health Department is owned and operated by the County of Santa Clara Magnitude of the problem

© 2012 Santa Clara County Public Health Department The Public Health Department is owned and operated by the County of Santa Clara Magnitude of the problem 1 – 1 ½ inches of Hep B lab reports/wk received over the fax

© 2012 Santa Clara County Public Health Department The Public Health Department is owned and operated by the County of Santa Clara Our questions How accurate are the data we send off to CDPH? What proportion were not true cases (mis- classified)? What proportion were out of jurisdiction? What proportion had incomplete data? How meaningful are the data?

© 2012 Santa Clara County Public Health Department The Public Health Department is owned and operated by the County of Santa Clara CDPH intern to the rescue How complete are the data? Calculated completeness of lab reports* according to Title 17 Surveyed physicians of patients with unknown addresses; calculated prevalence of in-county patients Evaluated HBsAg lab results for confirmatory report

© 2012 Santa Clara County Public Health Department The Public Health Department is owned and operated by the County of Santa Clara CDPH intern to the rescue How accurate are the case classifications? Calculated sensitivity and positive predictive value of HBV classification What is the burden of reporting for county staff? Surveyed SCCPHD Staff Identified inefficiencies of the surveillance system

Findings

© 2012 Santa Clara County Public Health Department The Public Health Department is owned and operated by the County of Santa Clara Quest reports the majority of our chronic hepatitis B cases

© 2012 Santa Clara County Public Health Department The Public Health Department is owned and operated by the County of Santa Clara Title 17 requires labs to report certain variables

© 2012 Santa Clara County Public Health Department The Public Health Department is owned and operated by the County of Santa Clara Patient variables that labs actually report: Name99% Age99% Gender99% Address35% (Quest reported < 1%) Phone72% (Quest reported 68%)

© 2012 Santa Clara County Public Health Department The Public Health Department is owned and operated by the County of Santa Clara Provider variables that labs actually report: Phone63% (Kaiser and ARUP 0%)

© 2012 Santa Clara County Public Health Department The Public Health Department is owned and operated by the County of Santa Clara Only 35% of reports have pt address, but most reports with no patient address ARE in jurisdiction Patients from Quest (334) Address (1) Sample (123) Received responses (113) Santa Clara County resident (105) Out of jurisdiction (8) Prevalence of in-county patients in sample = 92.9% (95% CI = 86.53% %) No Address (333) 15

© 2012 Santa Clara County Public Health Department The Public Health Department is owned and operated by the County of Santa Clara The majority of lab reports are likely unconfirmed HBsAg

© 2012 Santa Clara County Public Health Department The Public Health Department is owned and operated by the County of Santa Clara Confirmed: case meets either of the laboratory criteria for diagnosis Probable: a person with a single HBsAg, HBV DNA, or HBeAg positive lab result and does not meet acute hepatitis B case definition How accurate are the case classifications that we report? Lab Criteria 1 Column 1 Column 2 (at least one of the following) IgM Anti-HBc NEGHBsAg POS HBeAg POS HBV DNA POS Lab Criteria 2 HBsAg = POS Positive 2 times at least six months apart HBeAg = POS HBV DNA = POS

© 2012 Santa Clara County Public Health Department The Public Health Department is owned and operated by the County of Santa Clara How accurate are the case classifications that we report? Percentage of cases misclassified: 56.79%

© 2012 Santa Clara County Public Health Department The Public Health Department is owned and operated by the County of Santa Clara What is the burden of reporting? 3 staff handle chronic Hep B reports 70 hrs/wk allotted to chronic Hep B surveillance; takes 83 hrs to do the work 20 hrs identifying patients that met the case def 10 hrs collecting info on cases or potential cases 50 hrs entering or modifying cases in CalREDIE 3 hrs analyzing data on cases Main finding: not enough time to do the work

© 2012 Santa Clara County Public Health Department The Public Health Department is owned and operated by the County of Santa Clara In summary Lots of misclassification Lots of missing information (Quest and ARUP biggest offenders) Despite missing address info, most cases were SCC residents Burden of surveillance system significant

© 2012 Santa Clara County Public Health Department The Public Health Department is owned and operated by the County of Santa Clara The bigger questions Value of data: cost of data Will ELR reduce the cost of Hep B surveillance? Data for action? What are our public health surveillance goals? identify acute cases, investigate potential novel sources identify pregnant women with chronic hep B characterize population with chronic hep B measure success of interventions and programs Is population based surveillance the answer?

© 2012 Santa Clara County Public Health Department The Public Health Department is owned and operated by the County of Santa Clara CDPH Myra Martinez Daryl Kong Kathleen Winter Kathy Harriman SCCPHD Shilpa Jani Aileen Arellano Laura Tang Debra Duran Acknowledgements