1 / 26

Periodic Traveling Waves of Dengue Hemorrhagic Fever in Thailand Donald Burke and Derek Cummings University of Pittsbur

Periodic Traveling Waves of Dengue Hemorrhagic Fever in Thailand Donald Burke and Derek Cummings University of Pittsburgh Graduate School of Public Health. Dengue Virus. Family Flaviviridae Mosquito-borne Four antigenically distinct serotypes Albert Sabin 1 and 2

kostya
Download Presentation

Periodic Traveling Waves of Dengue Hemorrhagic Fever in Thailand Donald Burke and Derek Cummings University of Pittsbur

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Periodic Traveling Waves of Dengue Hemorrhagic Fever in Thailand Donald Burke and Derek Cummings University of Pittsburgh Graduate School of Public Health

  2. Dengue Virus • Family Flaviviridae • Mosquito-borne • Four antigenically distinct serotypes • Albert Sabin 1 and 2 • William Hammon and Gladys • Sather isolated 3 and 4 (GSPH) • Most important mosquito-vector is • Aedes aegypti

  3. DHF/DSS Associated with Secondary Infections Each serotype induces life-long immunity Infection with a second serotype is a risk factor for development of DHF Caused by a phenomenon called Antibody Dependent Enhancement In vitro evidence suggests secondary infections are more transmissible

  4. Clinical Manifestations of Dengue and Dengue Hemorrhagic Fever WHO/TDR/Crump

  5. DHF Incidence in Bangkok, Thailand 1965-1999 (Cases/10000) All four serotypes co-circulate in Bangkok

  6. Infectious Disease Data Often Show Multiple Periodicities Monthly measles incidence in New York City, US, 1928-1965

  7. Source of Incidence Data Monthly DHF Incidence Passive Surveillance 72 Provinces 1983-1996 Gathered by Thai Ministry of Public Health, serologically confirmed to the extent logistically possible. (~20%) ~850,000 cases

  8. Log of Raw Incidence of DHF in Thailand N S Log(Incidence/1000) Rank of Province Year

  9. Decomposition of Time Series Using the Empiric Mode Decomposition

  10. Log of DHF Incidence in Bangkok 1984 1988 1990 1992 1994 1996 1986

  11. Three Year Periodic Mode of DHF Incidence In Bangkok

  12. Lags at Which Correlation Between Bangkok and other Provinces Is Maximized p<1e-8 ~148 km/month (months)

  13. 427: 344-7 (2004) Traveling waves in the occurrence of dengue hemorrhagic fever in Thailand DEREK A.T. CUMMINGS, RAFAEL A. IRIZARRY, NORDEN E. HUANG, TIMOTHY P. ENDY, ANANDA NISALAK, KUMNUAN UNGCHUSAK & DONALD S. BURKE

  14. Comparison of Bangkok with all other provinces showed Bangkok to the best center of these recurrent waves by several metrics

  15. Hypothesis Cycles caused by predator-prey interaction of serotypes and susceptible population

  16. DEN-1 DEN-2 DEN-3 DEN-4 100% DEN-4 80% DEN-3 60% % of dengue serotypes isolated from patients 40% DEN-2 20% DEN-1 0% 1974 1976 1978 1980 1982 1984 1986 1988 1990 1992 1994 1996 1998 2000 2002 YEAR Endy et al., 2001

  17. Schematic Basic SIR model births Susceptible Recovered Infectious deaths deaths deaths

  18. Four Serotype Transmission Model

  19. Results of Simulations show many features of incidence time series Year Cummings, et al, PNAS, 2005

  20. Billings L, Schwartz IB, Shaw LB, McCrary M, Burke DS, Cummings DA. Instabilities in multiserotype disease models with antibody-dependent enhancement.J Theor Biol. 2007 May 7;246(1):18-27. Epub 2006 Dec 28. Schwartz IB, Shaw LB, Cummings DA, Billings L, McCrary M, Burke DS.Chaotic desynchronization of multistrain diseases.Phys Rev E Stat Nonlin Soft Matter Phys. 2005 Dec;72(6 Pt 2):066201. Epub 2005 Dec 1. Cummings DA, Schwartz IB, Billings L, Shaw LB, Burke DS.Dynamic effects of antibody-dependent enhancement on the fitness of viruses.Proc Natl Acad Sci U S A. 2005 Oct 18;102(42):15259-64. Epub 2005 Oct 10.

  21. Trials of candidate dengue vaccines have begun and more are planned Vaccines have the potential to shift population level immunity dramatically Simulation models could aid in the design of trials and ultimately planning of vaccination programs

  22. Conclusions • DHF incidence data shows intricate spatial temporal patterns • Patterns may elucidate underlying dynamics of serotype interactions and cycling of immunity in the population • Simple models can reproduce some of the dynamic behaviors observed in time series • A detailed understanding of dynamics could help evaluate and design control programs

  23. Collaborators Derek Cummings University of Pittsburgh Timothy Endy Walter Reed Army Institute of Research Ananda Nisalak Armed Forces Research Institute of Medical Sciences Rafael Irizarry Johns Hopkins Bloomberg School of Public Health Norden Huang NASA Goddard Space Center Kumnuan Ungchusak Ministry of Health of Thailand Ira Schwartz Naval Research Laboratories Robert Gibbons Armed Forces Research Institute of Medical Sciences

More Related