Epidemiology of Rabies

1
Epidemiology of Rabies

• John R. Dunn, DVM, PhD
• Communicable and Environmental Diseases
• Tennessee Department of Health
• Centers for Disease Control and Prevention

2
Overview

• Rabies virus
• Rabies epidemiology in the US and Tennessee
• Skunk rabies
• Raccoon rabies and ORV
• Guidance documents
• ACIP Pre-exposure vaccination
• Compendium

3
Rabies virus- Lyssavirus

• Rhabdoviridae- bullet shaped RNA virus
• Neurotropic, fatal encephalitis
• Variants- host adapted

4
Transmission

• Transmission BITE of a RABID animal
• Virus-laden saliva contacts nerves
• Saliva in fresh cut or abrasion, mucous membranes
  (scratch?-- no)
• Person to person theoretical risk, never
  documented in health care worker

5
Rabies Epidemiology in the United States
6

• Human rabies in US 2 5 cases / year
• Tennessee case 2002
• PEP 100 effective
• 40,000 treatments/ year
• 2000 6,000 / treatment
• 75 unnecessary based on rabies risk
• Animal rabies 7,000 8,000 cases / year
  (wildlife)
• 4 variants raccoon, skunk, bat, fox
• Canine variant no longer enzootic in US

7
(No Transcript)
8
(No Transcript)
9
(No Transcript)
10
(No Transcript)
11
Terrestrial Wildlife Rabies
12
(No Transcript)
13
(No Transcript)
14
(No Transcript)
15
Bat Rabies
16
(No Transcript)
17
Bat-associated Rabies

• U.S.- majority of human rabies caused by bats
• From 1980-2000, 26/35 (74) cases
• Silver-haired/Eastern pipistrelle bat
• Minor wound from bat bite
• Difficult to detect
• Persons may not recognize exposure
• Most human rabies diagnosed post-mortem
• Not on differential
• Healthcare workers exposed

18
Rabies Epidemiology in Tennessee
19
Rabies Testing by the Tennessee Department of
Health (TDH)

• Three testing centers
• Nashville
• Knoxville
• Jackson
• Rabies Diagnosis Direct Fluorescent Antibody
  testing (DFA) of brain tissue
• Testing performed free of charge
• Not much attention paid to number and
  characteristics of negative results

20
Results from 2005

• Review of laboratory slips from 3 testing centers
  in 2005
• 2017 animal submissions
• 2010 submitted to testing centers in TN
• 92 (96) of 95 counties
• 362 different localities
• 18 out-of-state
• 7 additional specimens from USDA-WS surveillance
  program (submitted to CDC)

21
(No Transcript)
22
(No Transcript)
23

N4 Cat 2001 (1), 2003 (1) Cow 2002 (1)
Opossum 2004 (1)
24
TN Rabies Positives (n48) by County, 2005
Pickett
Hancock
Sullivan
Clay
Johnson S - 1
Claiborne
Stewart
Montgomery
Robertson
Sumner S - 1
Macon
Hawkins
Scott
Washington R-1, S-1
Campbell B - 1
Fentress
Trousdale
Carter R - 2
Lake
Jackson
Henry
Obion
Overton
Weakley
Grainger
Union
Houston
Greene S 1 D - 1
Cheatham
Unicoi F 1 R-1
Hamblen
Smith
Putnam B - 1
Davidson B - 2
Morgan
Dickson
Wilson S - 1
Knox B 4 F-1
Dyer
Jefferson
Gibson
Humphreys
Carroll
Cocke S - 2
Dekalb
Cumberland
White
Rutherford S 5 H - 1
Williamson S - 4
Benton
Roane
Crockett
Sevier
Hickman
B - 1 Van Buren
Cannon
Lauderdale
Loudon
Blount
Henderson
Perry
Warren
Madison
Maury B - 1
Haywood
Rhea
Lewis F - 1
Tipton
Decatur
Bledsoe
Bedford S - 2
Coffee S-1
Chester
Monroe B - 1
Meigs
McMinn
Marshall
Grundy
Sequatchie
Moore
Shelby B - 2
Giles S - 1
Hamilton B 2 S - 1
Fayette
Hardeman
McNairy
Hardin
Marion B - 1
Franklin
Bradley
Polk
Wayne
Lawrence
Lincoln S - 2
Bat - - - - - - - 16 Horse---- 1 Skunk -
- - - - 23 Fox - - - - 3 Raccoon - - - -4
Dog - - - - 1

25
TN Rabies Positives (n26) by County, 15 April
2006
Pickett
Hancock
Sullivan
Clay
Johnson
Claiborne
Stewart
Montgomery
Robertson
Sumner
Macon
Hawkins
Scott
Campbell
Washington
Fentress
Trousdale
Carter
Lake
Jackson
Henry
Obion
Overton
Weakley
Grainger
Union
Houston
Cheatham
Greene
Unicoi C 1
Hamblen
Smith
Davidson S - 2
Morgan
Dickson
Wilson
Putnam
Dyer
Jefferson S-1
Gibson
Knox
Humphreys
Carroll
Cocke
Dekalb
Cumberland
White
Williamson S - 4
Benton
Roane
Rutherford S 10
Crockett
Sevier
Hickman
Van Buren
Cannon
Lauderdale
Loudon
Blount
Henderson
Perry
Warren S-1
Madison
Maury
Haywood
Rhea
Lewis
Tipton
Decatur
Bledsoe
Bedford D - 1
Coffee
Chester
Monroe
Meigs
McMinn
Marshall
Grundy
Sequatchie
Moore S-3
Shelby
Giles
Hamilton
Fayette
Hardeman
McNairy
Hardin
Marion
Franklin
Bradley F-1
Polk
Wayne
Lawrence
Lincoln S - 1
Skunk - - 23 Fox - - 1 (Racc Var) Cat
------- 1 (Racc Var) Dog - 1 (Sk Var)

26
(No Transcript)
27
(No Transcript)
28
East TN counties with raccoon variant rabies,
2002-Apr 15, 2006
Pickett
Hancock
Sullivan
Claiborne
Johnson
Hawkins
Scott
Campbell
Fentress
Washington
Carter
Overton
Union
Grainger
Greene
Hamblen
Putnam
Unicoi
Anderson
Morgan
Jefferson
Knox
Cocke
Dekalb
Cumberland
White
Roane
Sevier
Van Buren
Loudon
Blount
Warren
Rhea
Bledsoe
Monroe
McMinn
Sequatchie
Grundy
Meigs
Bradley
Marion
Hamilton
Polk
29
Why is raccoon rabies problematic?

• Raccoons thrive in suburban settings
• Aggressive and swift
• Increase in dog and cat (2X) rabies
• Increase in other rabid species (foxes,
  groundhogs, livestock, etc.)
• Increase in human exposures and need for PEP risk
  assessment
• Increased animal control calls anxiety

30
Tennessee response to raccoon rabies

• Education
• Reducing risk
• Protecting pets through vaccination
• Increase surveillance
• USDA-Wildlife Services (gt 20 East TN counties)
• Oral rabies vaccination (ORV) campaign
• Appalachian Ridge baiting
• GAT baiting

31
Anticipated ORV Barrier Zone for Raccoon Rabies
in the United States
2004 cases
Proposed ORV
32
ORV in Tennessee, 2005
Appalachain Ridge
GAT
33
(No Transcript)
34
Guidance documents
35
http//www.cdc.gov/mmwr/PDF/rr/rr4801.pdf
36
Imovax (Sanofi Pasteur)

• Previously used off-label, 0.1ml intradermal for
  pre-exposure vaccination
• TDH no longer advocating use of Imovax off-label
  consistent with new ACIP recommendations
• Important for state, regional and local HD to
  promote rabies vaccination for at-risk persons

37
http//s94745432.onlinehome.us/RabiesCompendium.pd
f
38
Questions?John DunnTennessee Department of
HealthCommunicable and Environmental
Diseases4th Floor, Cordell Hull Building425 5th
Avenue NorthNashville, TN 3724615.741.7247