Animal Bite Surveillance Evaluation Update

1
Animal Bite Surveillance Evaluation Update

• Aron J. Hall, DVM, MSPH
• CDC Epidemic Intelligence Service Officer
• West Virginia Dept of Health Human Resources

2
Public Health Importance

• Rabies universally fatal, but preventable
• Post-exposure prophylaxis (PEP)
• Pet and wildlife vaccination
• High-risk individual vaccination

3
Animal Bites in the U.S.

• 1 in 2 people bitten during lifetime
• 5 million bites annually
• PEP 30,000 treatments annually ? 50 million
• Dogs 80-90 of all bites
• 1 in 20 dogs will bite during its lifetime

CDC. MMWR 2003 52(26)605-10 Moore DA et al.
JAVMA 2000 217(2)190-4
4
West Virginia Electronic Disease Surveillance
System (WVEDSS)

• 63 reportable diseases and events
• Jan 1, 2007 Production version
• July 2, 2007 Use mandated
• System Purposes
• Prevent human rabies infection
• Identify risk factors for victims
• Assess appropriateness of PEP use

5
Initial Evaluation

• 2006 pilot version
• Informal interviews
• Dataset analysis of animal bite cases
• Web-based survey of local health departments
  (LHDs)

6
Conclusions of Initial Evaluation

• Important surveillance activity
• Potentially powerful system
• Resource intensive
• Lack of standardization limits utility and
  consistency
• Form issues central to acceptability
• Case investigations timely
• Key variables complete

7
Recommendations of Initial Evaluation

• Revisions to the reporting form
• Development of case definition and surveillance
  protocol
• LHD training on WVEDSS and animal bite protocol
• Timely data evaluation and LHD feedback

8
Recommendations of Initial Evaluation

• Revisions to the reporting form
• Development of case definition and surveillance
  protocol
• LHD training on WVEDSS and animal bite protocol
• Timely data evaluation and LHD feedback

• Jan 2007
• Jan 2007
• May 2007
• Ongoing

9
Re-evaluation Objectives

• Assess use of new case definition
• Assess use of WVEDSS for reporting
• Evaluate system performance
• Evaluate system acceptability and simplicity
• Identify further potential improvements

10
Re-evaluation Methods

• Similar to 2006 evaluation
• Dataset analysis
• JanJune 2007 725 animal bite cases
• JanJune 2006 503 animal bite cases
• Web-based survey of LHDs
• 100 of 49 LHDs responded (both years)

11
Case Definition

• Vector species exposure (includes bats and
  terrestrial mammals, especially carnivores)
• Bite
• Scratch
• Introduction of saliva or central nervous system
  tissue into a fresh wound or mucous membrane
• Any contact with a bat in which a bite cannot be
  ruled out
• person sleeping in a room with a bat
• finding a bat in the room with an unattended
  child, mentally impaired or intoxicated person

12
Cases ReportedJanJune 2007

• Species
• 70.9 dogs
• 23.6 cats
• 1.4 raccoons
• 1.4 bats
• 2.8 others
• Rodents, fox, ferret, goat, sheep, rabbit,
  groundhog, zebra, bobcat, opossum

• Exposures
• 69.9 punctures
• 16.8 superficial bites
• 7.3 scratches
• 1.4 unknown (bats)
• 1.1 mucous membrane
• 3.4 others
• Bites, broken skin, open wound, laceration,
  clawed, saliva

13
Reportable Exposure SourcesLHD Survey (N49)
14
Reportable Exposure SourcesLHD Survey (N49)
15
Reportable Exposure TypesLHD Survey (N49)
16
Reportable Bat Exposure TypesLHD Survey (N49)
17
Use of WVEDSS

• JanJune 2006
• 1125 WVEDSS reports
• 575 (51) animal bites
• 1255 animal bites reported to LHDs
• 503 (40) reported in WVEDSS
• 663 (53) reported by paper

• JanJune 2007
• 1578 WVEDSS reports
• 929 (59) animal bites
• 1201 animal bites reported to LHDs
• 929 (77) reported in WVEDSS
• 272 (23) reported by paper

18
Completeness of Key Variables in Animal Bite
Reports
19
Completeness of Key Variables in Animal Bite
Reports
20
Animal Bite Case Investigation
Bite Occurred
LHD Notified
PEP Initiated
Animal Confined
Head Submitted
Owner Notified
Reported in WVEDSS
Received
Completed Checked
Lab Results Reported
21
Timeliness of Animal Bite Case Investigations
(days from bite)
22
Timeliness of Animal Bite Case Investigations
(days from bite)
23
Post-Exposure Prophylaxis (PEP)

• Given in 38 (5.2) of 725 cases
• 9 completed series
• 18 did not complete series
• 11 missing
• Of 96 heads tested, 4 were positive
• Only 1 of these 4 cases indicated completion of
  PEP series

24
(No Transcript)
25
(No Transcript)
26
(No Transcript)
27
(No Transcript)
28
(No Transcript)
29
(No Transcript)
30
Potential Improvements
31
Conclusions

• Case definition generally used appropriately
• Inconsistent reporting of exposure and species
• Some misunderstanding of vector species
• Increased overall WVEDSS use
• Slightly increased proportion were animal bites
• Significantly increased proportion of animal
  bites reported via WVEDSS

32
Conclusions

• Improved timeliness and completeness of key
  variables
• Gaps in PEP follow up
• Improved acceptability and simplicity
• Continued improvements to reporting form needed

33
Recommendations

• Further revisions to WVEDSS form
• LHD training on management and reporting of
  animal bites
• Timely data analysis and feedback
• Re-evaluate after mandated WVEDSS use

34
Acknowledgements

• Sharon Hill, Epidemiologist
• Danae Bixler, IDEP Director
• Loretta Haddy, State Epidemiologist
• Susan Stowers, Data Analyst
• Robert Fernatt, WVEDSS Manager
• IDEP Epidemiologists
• Regional Epidemiologists
• LHD Sanitarians, Nurses, Clerical Staff,
  Administrators, and Medical Officers

35
The findings and conclusions in this presentation
are those of the author and do not necessarily
represent the views of the Centers for Disease
Control and Prevention.
36
Extra Slides to follow
37
(No Transcript)
38
(No Transcript)
39
(No Transcript)
40
Appropriateness of PEP Use
Animal Bite 503
Species of Concern 493
Animal Confined 349
Killed Tested 40
Animal Unavailable 104
Endemic County or Bat 54
Rabies Positive 7
Unknown Final Status 44
PEP Given 19 (35)
PEP Given 6 (86)
PEP Given 0 (0)
41
Flexibility and Stability

• WVEDSS currently in transition
• Pilot phase
• Subject to changes
• Variation among LHDs
• Difficult to make form revisions
• Production version promises improvement

42
Representativeness
43
Predictive Value Positive (PVP)

• Could not be calculated
• Review process helps validate report before being
  closed and confirmed

44
Post-Exposure Prophylaxis (PEP)

• Wound treatment
• Human rabies immune globulin (RIG) into wound on
  day 0
• Rabies vaccine on days 0, 3, 7, 14, and 28
• If prior vaccination ? vaccine on days 0 and 3
  only

45
Indices of FrequencyAnimal Bites

• 1 in 2 Americans will be bitten in their lifetime
• Estimated 2 million annual mammalian bite wounds
• 1 of all ED visits
• 30 million in annual health care costs
• Dogs
• Account for 80-90 of all bites
• 1 in 20 dogs will bite a human in its lifetime

46
System Components

• Data collection daily, ongoing
• Data stored and managed centrally at state health
  department
• Weekly electronic reports distributed to LHDs and
  various offices of WV Bureau for Public Health

47
Animal Bite Reporting SourcesLHD Survey (n49)
48
Reportable Animal ExposuresLHD Survey (n49)
49
Reportable Animal ExposuresLHD Survey (n49)
50
Local Health Department (LHD) Personnel Resources
51
Post-Exposure Prophylaxis (PEP)

• 3 human rabies cases annually in U.S.
• Healthy People 2000 objective
• 9,000 annual PEP treatments
• Estimated 16,000 to 39,000 PEP treatments
  annually in U.S.
• 700 to 1700 per course of treatment
• Annual cost of 26.5 to 65.3 million

52
Usefulness