Use of Electronic Death Certificates for Influenza Death Surveillance1 - Volume 20, Number 1—January 2014 - Emerging Infectious Disease journal - CDC

HERE full-text ►
Use of Electronic Death Certificates for Influenza Death Surveillance1 - Volume 20, Number 1—January 2014 - Emerging Infectious Disease journal - CDC

Volume 20, Number 1—January 2014

Research

Use of Electronic Death Certificates for Influenza Death Surveillance1

Article Contents

• Methods
• Results
• Discussion
• Acknowledgment
• References
• Figure 1
• Figure 2
• Figure 3
• Table 1
• Table 2
• Table 3
• Suggested Citation

Elizabeth A. Bancroft2  and Sun Lee

Author affiliations: Los Angeles County Department of Public Health, Los Angeles, California, USA

Suggested citation for this article

Abstract

Surveillance for influenza deaths has been used to gauge the severity of influenza seasons. Traditional surveillance, which relies on medical records review and laboratory testing, might not be sustainable during a pandemic. We examined whether electronic death certificates might provide a surveillance alternative. We compared information retrieved from electronic death certificates that listed influenza (or a synonym) with information retrieved from medical charts on which influenza deaths were reported by traditional means in Los Angeles County, California, USA, during the 2009 influenza A(H1N1) pandemic and 2 subsequent influenza seasons. Electronic death certificate surveillance provided timely information, matched the demographics and epidemiologic curve of that obtained from traditional influenza-related death surveillance, and had a moderately positive predictive value. However, risk factors were underreported on death certificates. Because surveillance by electronic death certificates does not require obtaining and reviewing medical records, it requires fewer resources and is less burdensome on public health staff.

Each year in the United States, more deaths are estimated to be caused by influenza than by AIDS (1,2). Influenza viruses commonly mutate, and concern that a new influenza pandemic will arise is always present. Hence, extensive clinical, syndromic, and virologic surveillance for influenza is conducted in the United States and worldwide. For determining the severity of each influenza season, recording the number of deaths from influenza has long been part of the national system. Although in the United States, most estimates of influenza deaths use a complex algorithm involving data from death certificates and virologic surveillance, in select situations, case reports of individual deaths are used (3,4). For example, since 2004, influenza-related deaths among children have been nationally reportable, and during the 2009 influenza A(H1N1) pandemic, laboratory-confirmed influenza-related deaths among persons of all ages were reported by state health departments to the Centers for Disease Control and Prevention (5,6).

Individual case reports (ICRs) of laboratory-confirmed influenza-related deaths provide useful information about the strain of influenza that caused the death, the demographic characteristics of the persons who died, and traditional and novel risk factors for death (7–9). Deaths are initially reported to health departments by hospitals, physicians, and medical examiners. Health departments collect medical records, laboratory results, specimens for confirmation at public health laboratories, and occasionally interviews of health care providers to determine whether the initial case report meets the definition of a laboratory-confirmed influenza-related death (5).

However, collecting and reviewing detailed medical records and laboratory confirmation reports can be time-consuming and labor-intensive. During pandemics, the infrastructure and resources needed to perform public health surveillance of individual influenza deaths can become limited right when the demand for knowledge about disease trends increases. Resources for performing a full, or even limited, investigation of individual influenza-associated deaths might not be available (10). Therefore, during pandemics, automated surveillance systems might prove useful for influenza death surveillance.

To evaluate usefulness of an automated influenza death reporting system during and after the 2009 influenza A(H1N1) pandemic, we investigated all death certificates in Los Angeles County, California, USA, on which influenza was listed as a direct or indirect cause of death from August 2009 through April 2012. We compared the sensitivity, positive predictive value, and timeliness of an electronic death reporting system (EDRS) with that of traditional influenza death surveillance based on ICRs.

Acknowledgment

We thank all those who tested, identified, treated, and reported influenza cases during 2009–2010 in Los Angeles County.

References

1. Centers for Disease Control and Prevention. Estimates of deaths associated with seasonal influenza̶ United States, 1976–2007. MMWR Morb Mortal Wkly Rep.2010;59:1057–62 .PubMed
2. Centers for Disease Control and Prevention. HIV surveillance report, 2011 [cited 2013 Mar 1].http://www.cdc.gov/hiv/topics/surveillance/resources/reports/
3. Thompson WW, Moore MR, Weintraub E, Cheng P-Y, Jin X, Bridges CB, Estimated influenza-associated deaths in the United States. Am J Public Health. 2009;99(Suppl 2):S225–30 and. DOIPubMed
4. Thompson WW, Weintraub E, Dhankhar P, Cheng P-Y, Brammer L, Meltzer MI, Estimates of US influenza-associated deaths made using four different models. Influenza Other Respi Viruses. 2009;3:37–49. DOIPubMed
5. Council of State and Territorial Epidemiologists. Influenza-associated pediatric mortality.2004 [cited 2013 Mar 1].http://c.ymcdn.com/sites/www.cste.org/resource/resmgr/PS/04-ID-04-FINAL.pdf 
6. Centers for Disease Control and Prevention. The 2009 H1N1 pandemic: summary highlights, April 2009–April 2010. 2010 [cited 2013 Mar 1].http://www.cdc.gov/h1n1flu/cdcresponse.htm#Ongoing_Surveillance_And_Response
7. Lee EH, Wu C, Lee EU, Stoute A, Hanson H, Cook HA, Fatalities associated with the 2009 H1N1 influenza A virus in New York City. Clin Infect Dis. 2010;50:1498–504 . DOIPubMed
8. Cox CM, Blanton L, Dhara R, Brammer L, Finelli L. Pandemic influenza A (H1N1) deaths among children—United States, 2009–2010. Clin Infect Dis. 2011;52(Suppl 1):S69–74 . DOIPubMed
9. Pebody RG, McLean E, Zhao H, Cleary P, Bracebridge S, Foster K, Pandemic influenza A (H1N1) 2009 and mortality in the United Kingdom: risk factors for death, April 2009 to March 2010. Euro Surveill. 2010;15:19571 .PubMed
10. Lipsitch M, Hayden FG, Cowling BJ, Leung GM. How to maintain surveillance for novel influenza A H1N1 when there are too many cases to count. Lancet. 2009;374:1209–11 . DOIPubMed
11. Centers for Disease Control and Prevention. Overview of influenza surveillance in the United States. 2012 [cited 2013 Mar 1].http://www.cdc.gov/flu/weekly/overview.htm#Mortality
12. Louie JK, Acosta M, Samuel MC, Schechter R, Vugia DJ, Harriman K, A novel risk factor for a novel virus: obesity and 2009 pandemic influenza A (H1N1). Clin Infect Dis.2011;52:301–12 and. DOIPubMed
13. Yang L, Chan KP, Cowling BJ, Chiu SS, Chan KH, Peiris JS, Excess mortality associated with the 2009 pandemic of influenza A(H1N1) in Hong Kong. Epidemiol Infect.2012;140:1542–50 . DOIPubMed
14. Dawood FS, Iuliano AD, Reed C, Meltzer MI, Shay DK, Cheng PY, Estimated global mortality associated with the first 12 months of 2009 pandemic influenza A H1N1 virus circulation: a modeling study. Lancet Infect Dis. 2012;12:687–95 . DOIPubMed
15. National Association for Public Health Statistics and Information Systems. Electronic systems [cited 2013 Sep 10].http://www.naphsis.org/Pages/ElectronicSystems.aspx

Figures

• Figure 1. [[caption]]
• Figure 2. [[caption]]
• Figure 3. [[caption]]

Tables

• Table 1. Demographic variables associated with influenza-related deaths obtained by 2 surveillance systems, Los Angeles County, California, USA, 2009–2010
• Table 2. Comparison of underlying variables associated with influenza-related deaths obtained by 2 surveillance systems, Los Angeles County, California, USA, 2009–2010
• Table 3. Comparison of lag times associated with reporting influenza-related deaths obtained by 2 surveillance systems, Los Angeles County, California, USA, 2009–2010

Suggested citation for this article: Bancroft EA, Lee S. Use of electronic death certificates for influenza death surveillance. Emerg Infect Dis [Internet]. 2014 Jan [date cited].http://dx.doi.org/10.3201/eid2001.130471

DOI: 10.3201/eid2001.130471

1These data were presented in part at the 139th American Public Health Association Annual Meeting, 2011 October 29–November 2, Washington, DC.

2Current affiliation: Independent consultant, New York, New York, USA.