Dengue Fever Outbreak in Hawaii
Dengue Fever
Outbreak
in
Hawaii
Dengue Virus
• Is an arbovirus • Has 4 serotypes (DEN-1, 2, 3, 4)• Transmitted by infected Aedes mosquitoes
- daytime feeder • Causes dengue fever, dengue
hemorrhagic fever, and dengue shock syndrome
World Distribution of Dengue 2000
Areas infested with Aedes aegyptiAreas with Aedes aegypti and recent epidemic dengue
hEpidemics in 1852, 1856, 1903
hLast endemic dengue transmission during 1943 DEN-1 epidemic
hA total of 18 confirmed cases of imported dengue between 1992 and 2000(mean=2, range 0-8)
Past Dengue in Hawaii
State of HAWAII
Kauai
Oahu
Maui
Hawaii
Lanai
Molokai
Niihau(900,00)
(125,000)
(60,00)
HanaLahaina
Nahiku
Kihei
MAUI
Timeline of Events in 2001
JulyIncreased imported cases (12)
Aug 3Statewide Doctor Alert
Sep 12Maui DOH calledabout illness
Timeline of Events in 2001
JulyIncreased imported cases (12)
Aug 3Statewide Doctor Alert
Sep 12Maui DOH calledabout illness
Sep 21CDC confirms dengue
Sep 24Enhanced surveillance operational
Surveillance for DenguePhysicians requested to test persons with clinically
compatible illness:
Fever (or chills) and 2 or more of the following symptoms:
- Headache- Eye or retro-orbital pain- Myalgia- Arthralgia- Rash- Any hemorrhagic manifestation
Surveillance for Dengue IICase Definition :
• Culture positive for dengue virus (13%)
• IgM antibody positive (83%)• IgG antibody positive in a person tested >2
months post onset of clinically compatible illness and linked to another IgM/culture positive case (4%)
Results
Between Sep 12, 2001 and Mar 15, 2002:
• >1700 reported “suspected” cases investigated
• 76% of these individuals met clinically compatible illness criteria
Dengue Testing in Hawaii 3/15/02
Need draw 114
Pending 73
Other DZ 39
Lost to FU 90
Refused 245
Confirmed 118 (7%)
Negative 1005 (59%)
N=1714
Source: HDOH/Epidemiology Branch
Confirmed Dengue Cases 3/15/02
Gender Age group
Male60%
Female40%
11
20
8
15
24
29
5 5
1<10
10-19
20-29
30-39
40-49
50-59
60-69 70
+
unk
age group
Source: HDOH/Epidemiology Branch
Symptoms – Confirmed Infections
hFever 95 % (range: 100-104 F, m: 102 F)hMyalgia 92 %hHeadache 89 %hChills 85 %hArthralgia 73 %hRash 66 %hEye pain 58 %hN / V 48 %hDiarrhea 36 %hSore throat 25 %hNasal congestion 23 %hCough 21 %
Symptoms – Confirmed Infections
40 (34%) reported at least one hemorrhagic manifestation:
hPetechiae 24 %hHeavy menses 19 % (females)hBleeding gums 8 %hEpistaxis 8 %hMelena 4 %hPurpura 1 %hHematuria 1 %hHematemesis 1 %
Dengue Testing in Hawaii by Week of Illness Onset
0
50
100
150
200
15 '01
17 '01
19 '01
21 '01
23 '01
25 '01
27 '01
29 '01
31 '01
33 '01
35 '01
37 '01
39 '01
41 '01
43 '01
45 '01
47 '01
49 '01
51 '01
53 '01
2 '02
4 '02
6 '02
8 '02
10 '02
CDC CONF NEGATIVE Not Determined
First reported case
Confirmed Dengue Cases by Illness Onset Week-updated 3/15/02
0
5
10
15
5/20 6/3
6/1 7 7/1
7/1 5
7/29
8/12
8/26 9/9
9/23
10/ 7
10/2
1
11/ 4
11/ 1
8
12/2
12/1
6
12/ 3
0
1/13
1/2 7
2/10
2/2 4
week beginning
Maui Oahu Kauai
First reported case31 prior
May 31 Feb 9
Source: HDOH/Epidemiology Branch
73 (62%)
11 (9%)
9 (8%)
Mosquito Observations
• Aedes albopictus high densities in Nahiku and elsewhere
• Aedes aegypti not present in outbreak foci on Maui, Kauai, and Oahu
28/72 (39%) of participants infected
1/131 (1%) of participants infected
Household Serological Survey - Preliminary data
Late October 28, 2001
Origin of the Outbreak?
One outbreak with local spreadvs.
Simultaneous but separate outbreaks of dengue on three islands
Epidemiologic Findings -
• 73 (62%) of all confirmed infections from Hana area
• 4 of 10 Maui infections outside Hana area were linked to Hana area
• 1 of 4 Kauai infections linked to exposure in Hana area
• 0 of Oahu infections linked to Kauai or Maui
imported case
indigenous case
Hamoa
Hana
Nahiku
May 10
Imported and Local Dengue Cases by Month 2001
0
15
30
45Ja
n
Feb
Mar
c h
A pril
May
Jun
Jul
Aug
Sep
Oc t
Nov
D ec
Month
Tahiti Local
Source: HDOH/Epidemiology Branch
Dengue 1 Phylogeny
15 isolates from Hawaii residents - Den-1
El Salvador 9372
Costa Rica 93Colombia 87
61 Colombia 93Puerto Rico 93
97 Peru 93Ecuador 9189
AmericanGenotypeParaguay 91
55
Puerto Rico 85Trinidad 92Aruba 85Mexico 6
Thailand 8098
Thailand 80BThailand 86
100
100
Samoa 01ASamoa 01BSamoa 01C
Rarotonga 8962
Philippines 8477
Hawaii 01ATahiti 01Hawaii 01BHawaii 01C
100
Indonesia 89
98
Djibouti ADjibouti B
90
9999
Thailand 9064
Taiwan 86100
PacificGenotype
98
Cambodia ACambodia B
CDC/02Cambodia C
Dengue 1 Phylogeny IIThailand 86
Samoa 01ASamoa 01BSamoa 01C
99
Rarotonga 8962
Philippines 8477
Hawaii 01ATahiti 01Hawaii 01BHawaii 01C
100
Indonesia 89
98
99
Djibouti ADjibouti B
90
Thailand 9064
Taiwan 86100
98
Cambodia ACambodia BCambodia C
Public Health Education Intensive public health outreach on primary
dengue prevention and mosquito control• Town meetings by DOH and DOE educators• Distribution of >600,000 dengue brochures• Dengue website (www.hawaii.gov/doh/dengue) • Medical alerts to physicians• Press releases, public service announcements – TV,
radio• Fliers to Maui rental car agencies and hotels• Checkpoints along Hana highway – distribution of
fliers, repellant• Lectures on dengue at medical centers• CDC video tapes for physicians
Public Health Action
• Mosquito inspection and treatment of over 2,500 residences
• Aggressive mosquito control statewide (spraying, source reduction)
• On-site education on mosquito control and disease prevention
• County solid waste clean-up with on-site trash pickup
• Closure of camping grounds and off-roads in Hana
Conclusions• DEN-1 virus responsible for current outbreak
in Hawaii
• Virus transmitted locally by Aedes albopictus
• Local transmission likely the result of recent importation of dengue virus from endemic countries
• No DHF/DSS or fatal dengue infections identified to date
• DEN-1 virus responsible for current outbreak in Hawaii
• Virus transmitted locally by Aedes albopictus
• Local transmission likely the result of recent importation of dengue virus from endemic countries
• No DHF/DSS or fatal dengue infections identified to date
Future Plans• Continue surveillance for dengue fever, DHS,
DSS
• Enhance laboratory capacity to confirm dengue with serological and culture - consider NAATs
• Continue public education and awareness of dengue
• Continue promotion and implementation of mosquito control measures
• Continue surveillance for dengue fever, DHS, DSS
• Enhance laboratory capacity to confirm dengue with serological and culture - consider NAATs
• Continue public education and awareness of dengue
• Continue promotion and implementation of mosquito control measures
Future Plans• Conclude survey of visitors to better assess
risk
• Conduct formal mosquito surveys on all islands to assess for presence of Aedes aegypti
• Closely monitor future dengue activity in the Pacific and Asia
• Conclude survey of visitors to better assess risk
• Conduct formal mosquito surveys on all islands to assess for presence of Aedes aegypti
• Closely monitor future dengue activity in the Pacific and Asia
Acknowledgements• Vector Borne Diseases Division, Dengue
Branch, Centers for Disease Control and Prevention
• Department of Education• Hawaii Visitors and Convention Bureau• Department of Health • Maui District Health Office • Kauai District Health Office • Hawaii District Health Office
• Vector Borne Diseases Division, Dengue Branch, Centers for Disease Control and Prevention
• Department of Education• Hawaii Visitors and Convention Bureau• Department of Health • Maui District Health Office • Kauai District Health Office • Hawaii District Health Office
Mahalo