the epidemiology and disease burden of dengue fever · the epidemiology and disease burden of...
TRANSCRIPT
The Epidemiology and Disease Burden
of Dengue Fever
Duane J Gubler, DirectorSignature Research Program in Emerging Infectious Diseases
Duke-NUS Graduate Medical School, Singapore
and
Asia Pacific Institute of Tropical Medicine and Infectious
Diseases, Honolulu
Flavivirus Vaccination, Annecy, France, 6-8 Dec, 2010
The Epidemiology of Dengue
Global Trends
• Population growth in tropical developing countries
• Economic growth in Tropical developing countries
• Unprecedented urban growth
• Globalization (modern transportation)
Increased movement of people, animals, commodities, vectors and pathogens
• Deterioration of public health infrastructure
Average annual number of DF/DHF
cases reported to WHO, 1955-2007
908 15,497
122,174
295,554
479,848
968,564
0
200000
400000
600000
800000
1000000
1200000
1955-1959 1960-1969 1970-1979 1980-1989 1990-1999 2000-2007
Nu
mb
er
of
ca
se
s
0
10
20
30
40
50
60
70
Nu
mb
er
of
co
un
trie
s
Source: DengueNet
2007 data provisional
Expanding geographic
Distribution
Increased epidemic
activity
Hyperendemicity
Emergence of DHF
and increasing
Disease severity
The 20th
Century Re-emergence of Dengue
Global Distribution of Dengue Virus Serotypes, 2010
DEN-1
DEN-2
DEN-3
DEN-4
DEN-1
DEN-2
DEN-3
DEN-4
DEN-1
DEN-2
DEN-3
DEN-4
DEN-1
DEN-2
DEN-3
DEN-4
DEN-1
DEN-2
DEN-3
DEN-4
DEN-1
DEN-2
DEN-3
DEN-4
DEN-1
DEN-2
DEN-3
DEN-1
DEN-2
DEN-3
DEN-1
DEN-2
DEN-3
DEN-4 DEN-1
DEN-2
DEN-3
DEN-4
DEN-1
DEN-2
DEN-3
DEN-4
DEN-1
DEN-2
DEN-3
DEN-4
Adapted from Gubler,1998
DEN-4
Re-Emergence of Dengue in the Americas
0 8,822
77,480104,412
266,818
656,240
0
100000
200000
300000
400000
500000
600000
700000
1955-1959 1960-1969 1970-1979 1980-1989 1990-1999 2000-2007
Nu
mb
er
of
ca
se
s
0
5
10
15
20
25
30
35
40
45
Nu
mb
er
of
co
un
trie
s
Source: DengueNet
2007 data provisional
DENV-1
DENV-2
DENV-3
DENV-2
DENV-4
DENV-1
DENV-2
DENV-3
DENV-1
DENV-4
DENV-2
DENV-3
DHF DHF DHF
Newly introduced viruses
0
5
10
15
20
25
0
50
100
150
200
250
300
350
1958
1960
1962
1964
1966
1968
1970
1972
1974
1976
1978
1980
1982
1984
1986
1988
1990
1992
1994
1996
1998
2000
2002
2004
2006
2008
2010
Morbidity Case fatality
Source: Bureau of EpidemiologyData until 27th March 2010
Year
Morbidity
Morbidity and case fatality rate from DF/DHF/DSS , Thailand, 1958-2010
Case fatality
Dengue Incidence in Sri Lanka, 1989-2009Population Proportion (100,000)
Reported Incidence though passive surveillance :
2000 - 30/100,000 population
2004 - 80/100,000 population
2009 - 170/ 100,000 population
First epidemic of DHF
0
10
20
30
40
50
60
0
50
100
150
200
250
300
350
1966 1969 1972 1975 1978 1981 1984 1987 1990 1993 1996 1999 2002 2005 2008
Illn
es
s r
ate
s p
er
10
0,0
00
Year
DHF
DF
Premises index
Pre
mis
es
in
de
x
Incidence of DF/DHF in Singapore, 1966-2009
Data from Ministry of Health,
Singapore
0
200000
400000
600000
800000
1000000
1200000
1400000
1600000
1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008
Nu
mb
er
of
cases
Year
Number of cases recorded from three WHO regions- SEARO, WPRO and AMRO
AMRO
WPRO
SEARO
0
500
1000
1500
2000
2500
3000
3500
2000 2001 2002 2003 2004 2005 2006 2007 2008AMRO 92 140 255 164 71 159 193 317 585
WPRO 247 510 364 454 572 749 694 1159 674
SEARO 656 1097 1035 1202 1235 1766 1558 1966 1247
Nu
mb
er
of
death
s
Number of deaths reported
Beatty ME, Letson GW, Margolis HS., Phuket, Thailand October 17-19, 2008.
Total population at risk• 3.6 billion people at risk for symptomatic dengue
• 55% of the world population living in countries at risk
for locally acquired dengue infection
Burden of Dengue
Beatty ME, Letson GW, Margolis HS., Phuket, Thailand October 17-19, 2008.
Total dengue infections
• 270 million dengue infections annually
- 230 million asymptomatic infections
• Social impact of epidemic dengue
Burden of Dengue
Beatty ME, Letson GW, Margolis HS., Phuket, Thailand October 17-19, 2008.
Total symptomatic dengue cases• 34 million cases of dengue fever annually
• 2 million DHF cases annually
Total dengue deaths • 21,000 deaths annually
Burden of Dengue
Beatty ME, Letson GW, Margolis HS., Phuket, Thailand October 17-19, 2008.
New Dengue Estimates
Deaths
DSS
DHF
Dengue Fever
Asymptomatic Infections
At-Risk Population
21,000
2 million
34 million
230 million?
3.6 billion
Beatty ME, Letson GW, Margolis HS., Phuket, Thailand October 17-19, 2008.
Disease Cases Deaths
Estimated
Countries
Affected
Dengue 36 million 21,000 124
Yellow Fever* 200,000 30,000 >42
Japanese
Encephalitis*
50,000 >10,000>10
Malaria* 500 million >1 million >105
Comparison of dengue burden of disease with other mosquito borne diseases
* Adapted from: E. Callaway. Dengue fever climbs the social ladder. Nature 2007;
448:734-735.
23
Estimation of average annual national cost of
dengue morbidity and mortality associated with
2001–2005 official reports*
24
Annual costs and DALYs induced by dengue
illness in the Americas in 2010 US$ (2000-
2007)Cost breakdown (%)
Area
Total costs
(millions of
US$)
Ambul.
cases
Hosp.
cases Deaths
Cost per
capita
Cost per
case DALYs
5.4 45.5% 54.5% 0.0% 0.02 $3,154 18 North
America [1.8;10.7] [0;83] [17;100] [0;0] [0.01;0.03] [1684;4138] [7;35]
380.8 75.6% 22.7% 1.6% 2.74 $307 15 424 Central
America &
Mexico [212.1;596.7] [56;86] [12;41] [1;3] [1.53;4.3] [210;398] [11353;20423]
538.6 68.4% 29.2% 2.2% 4.50 $326 20 223 Andean sub-
region [271.3;877.5] [40;84] [14;57] [1;4] [2.27;7.33] [218;414] [13712;28872]
878.2 78.3% 19.5% 2.0% 4.64 $410 26 492 Brazil
[178.8;1996.7] [17;95] [4;76] [1;9] [0.94;10.55] [164;577] [11722;52947]
25.4 74.4% 24.5% 1.1% 0.41 $184 1 658 Southern
cone** [10.1;45.8] [39;90] [9;59] [1;3] [0.16;0.73] [109;227] [856;3009]
321.4 62.2% 31.7% 6.1% 8.29 $713 8 957 Caribbean
[224.5;438] [47;74] [20;46] [4;9] [5.79;11.29] [592;837] [7430;10588]
2,149.8 72.9% 24.4% 2.6% 2.42 $382 72 772 The
Americas [898.4;3965.4] [34;88] [10;61] [1.5;6.8] [1.01;4.47] [236;508] [45080;115874]
Aggregate financing of projected laboratory positive dengue cases by type of
cost and source of financing, average per year (2002-2007)
Source of
financing
Direct medical
costs
Direct non-
medical
costs
Indirect
costs
All types of
costs Row %
Insurance $5,369,180 $0 $0 $5,369,180 25%
Households $1,423,469 $489,180 $6,688,721 $8,601,370 41%
Employers $0 $0 $1,676,545 $1,676,545 8%
Government $4,978,607 $0 $456,641 $5,435,248 26%
Total $11,771,257 $489,180 $8,821,907 $21,082,343 100%
Column % 56% 2% 42% 100%
26
Comprehensive costs of dengue:
Thailand, Panama, and Puerto Rico
Item Thailand Panama
Puerto
Rico
Thailand vs
Panama
Population (million) 62 3.3 3.9
Cost of dengue illness (US $ million) $158 $11.8 $21.1
Per capita cost of illness $2.55 $3.58 $5.41 -29%
Cost of dengue vector control (US $ million) $62 $5.0 $7.7
Per capita cost of vector control $1.00 $1.52 $1.97 -34%
Total cost of dengue (US $ million) $220 $16.9 $28.8
Per capita cost of dengue $3.55 $5.22 $7.38 -32%
Per capita GDP $2,750 $4,630 $17,100 -31%
Dengue / GDP 0.13% 0.11% 0.04% 15%
Vector control share of dengue costs 28% 30% 27% -7%
Thailand based on officially reported cases only, $48 million
Armien B et al.: Am J Trop Med Hyg 2008, 79(3):364–371.
Kongsin S et al.; Dengue Bulletin 2010, in press.
Perez C et al.: Dengue Bulletin 2010, in press.
Halasa Y et al.: Unpublished data
Index mundi, CIA factbook - http://www.indexmundi.com/puerto_rico/gdp_per_capita_(ppp).html
Beatty ME, Letson GW, Margolis HS., Phuket, Thailand October 17-19, 2008.
Non endemic countries:
Risk to Travelers
• 125 million international tourists visited dengue
endemic countries in 2004* (United Nations World
Tourism Organization)
• 7% to 45% of febrile travelers returning from endemic
areas: Serological evidence of recent dengue
infection †
• Prospective study of Dutch travelers: 2.9% developed
symptomatic dengue‡
*http://www.unwto.org/index.php
† Wilder-Smith A, Schwartz E. Dengue in travelers. N Engl J Med. 2005 Sep 1;353(9):924-32.
‡Cobelens FG, Groen J, Osterhaus AD, Leentvaar-Kuipers A, Wertheim-van Dillen PM, Kager PA. Incidence and risk
factors of probable dengue virus infection among Dutch travellers to Asia. Trop Med Int Health. 2002 Apr;7(4):331-8.
Beatty ME, Letson GW, Margolis HS., Phuket, Thailand October 17-19, 2008.
Additional symptomatic dengue
cases from non endemic countries
• 125 million x 0.029
= 3.6 million dengue cases among travelers
Beatty ME, Letson GW, Margolis HS., Phuket, Thailand October 17-19, 2008.
What is the Impact of Epidemic Dengue on
Tourism? Commonwealth Games 2010
30
Potential impact of outbreak
on tourist revenuesCountry
or region
Average
expenditure US$
per foreign tourist
(latest period)
Potential impact
on tourism
revenues (US$
million)
Estimated
immediate cost[1]
(US$ million) for
comparison
Gujarat 1725[2] (2007) 7-43 90
Malaysia 857[3] (2007) 57-171 133
Thailand 980[4] (2006) 377-1132 127
[2] Investment Commission of India (2008)
[3] Tourism Malaysia (2008)
[4] Tourism Authority of Thailand (2008)
[1] Immediate cost = cost of illness + cost of intervention programmes as defined
in 1.1
*Tiina Murtola1,2, Tapasvi Puw ar3, Robert Field1, Hong-Fei Gong2, Dileep
Mavalankar3, Donald S. Shepard4, S.S. Vasan1,2. Quantifying the Impact of
Chikungunya and Dengue on Tourism Revenues. 2nd International Conference
on Tourism, Indian Institute of M
Approximate Global Distribution of Dengue and Aedes aegypti, by
State/Province, 2010
Areas with recent dengue transmission
Areas infested with Aedes aegyptiAdapted from Gubler, 1998
The Epidemiology and Disease Burden of
Dengue Fever
Conclusions
• Dengue has significant public health, economic and social
impact on populations in endemic countries
• Dengue is grossly under reported in most endemic
countries
• Dengue disease burden and cost are likewise grossly
under estimated
• There is a desperate need for good population-based
estimates of the economic cost of dengue
• Surveillance for dengue is very poor in most dengue
endemic countries