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