Volume 14, Number 7—July 2008
Research
Seasonality, Annual Trends, and Characteristics of Dengue among Ill Returned Travelers, 1997–2006
Figure 2
![Changes in dengue morbidity during regional epidemics. Heavy red and blue lines show dengue in returned travelers as a proportion of monthly morbidity in all ill returned travelers to Southeast Asia (A) and Thailand (B) during the epidemic years of 1998 and 2002 (red lines) and during all other nonepidemic years (blue lines). Black horizontal dashed lines represent mean proportionate morbidity over all months for that area during the cumulative 1997–2006 period in travelers; red horizontal dashed lines represent mean proportionate morbidity over all months during the 2 outbreak years (1998 and 2002) in travelers. Each gray line in panel B tracks month-by-month reports to the World Health Organization (WHO) of the total number of dengue cases in the endemic Thai population for a single year from 1998–2005. *Proportionate morbidity is expressed as number of dengue cases per 1,000 ill returned travelers.](/eid/images/07-1412-F2.jpg)
Figure 2. Changes in dengue morbidity during regional epidemics. Heavy red and blue lines show dengue in returned travelers as a proportion of monthly morbidity in all ill returned travelers to Southeast Asia (A) and Thailand (B) during the epidemic years of 1998 and 2002 (red lines) and during all other nonepidemic years (blue lines). Black horizontal dashed lines represent mean proportionate morbidity over all months for that area during the cumulative 1997–2006 period in travelers; red horizontal dashed lines represent mean proportionate morbidity over all months during the 2 outbreak years (1998 and 2002) in travelers. Each gray line in panel B tracks month-by-month reports to the World Health Organization (WHO) of the total number of dengue cases in the endemic Thai population for a single year from 1998–2005. *Proportionate morbidity is expressed as number of dengue cases per 1,000 ill returned travelers.
1In addition to the authors, members of the GeoSentinel Surveillance Network who contributed data are: Elizabeth Barnett, Boston University, Boston, Massachusetts, USA; Graham Brown, Royal Melbourne Hospital, Parkville, Victoria, Australia; Giampiero Carosi and Francesco Castelli, University of Brescia, Brescia, Italy; Lin Chen and Mary Wilson, Harvard University, Cambridge, Massachusetts, USA; Bradley Connor, Cornell University, New York, New York, USA; Jean Delmont and Philippe Parola, Hôpital Nord, Marseille, France; Devon Hale and Stefanie Gelman, University of Utah, Salt Lake City, Utah, USA; Elaine Jong and Jean Haulman, University of Washington, Seattle, Washington, USA; Phyllis Kozarsky and Carlos Franco, Emory University, Atlanta, Georgia, USA; Carmelo Licitra, Orlando Regional Health Center, Orlando, Florida, USA; Louis Loutan and Francois Chappuis, University of Geneva, Geneva, Switzerland; Poh Lian Lim, Tan Tock Seng Hospital, Singapore; Michael Lynch, Fresno International Travel Medical Center, Fresno, California, USA; Susan McLellan, Tulane University, New Orleans, Louisiana, USA; Prativa Pandey, CIWEC Clinic Travel Medicine Center, Kathmandu, Nepal; Cecilia Perret, Pontificia Universidad Católica de Chile, Santiago, Chile; Bradley Sack and Robin McKenzie, Johns Hopkins University, Baltimore, Maryland, USA; Hiroko Sagara, Yokohama Municipal Citizen's Hospital, Yokohama, Japan; Marc Shaw, Worldwise Travellers Health and Vaccination Centre, Auckland, New Zealand; Robert Steffan and Patricia Schlagenhauf, University of Zurich, Zurich, Switzerland; William Stauffer and Patricia Walker, University of Minnesota, Minneapolis, Minnesota, USA; and Murray Wittner, Albert Einstein School of Medicine, Bronx, New York, USA.