Malaria and its conquering

1. Malaria and its conquering Joel G. Breman, MD, DTPH Fogarty International Center National Institutes of Health Tropical Infectious Diseases Workshop Oswaldo Cruz Foundation (FIOCRUZ) Rio de Janeiro, Brazil 28 April–1 May 2003

2. Conquering Malaria • Ecology and burden • Interventions • Successes • Economics • Research questions • Controversies

3. Ecology and Burden

4. Malaria and Ecology and Burden Control and prevention measures Social, behavioral, economic and political factors Human Intrinsic and Extrinsic Factors Parasite Mosquito Environmental conditions

5. Hypoglycemia Anemia Acute febrile illness Severe illness Death Respiratory distress Cerebral malaria Infected Mosquito Anemia Chronic effects Impaired growth and development Neurologic/ cognitive Malnutrition Infected Human Developmental Low birth weight Infantmortality Fetus Pregnancy Acute illness Maternal Impaired productivity Anemia Malaria Ecology and BurdenClinical Manifestations

7. Global distribution of Plasmodium vivax maximum distribution 19th century (pink) late 20th century (purple) Mendis K, Sina B J, Marchesini P, Carter R (2001) The neglected burden of P.vivax malaria. American Journal of Tropical Medicine and Hygiene 64; Supplement titled "The Intolerable Burden of Malaria: A New Look at the Numbers" 1-106.

8. MARA/ARMA Model of Malaria Transmission, 2003

9. Deaths and Malaria-related Deaths (1000s), 2000

10. Disability–adjusted Life Years (DALYs, 1000s),All Cause and Malaria-related, 2002

11. Estimated World and Regional Malaria Deaths, 1952-1999

12. Disease Percentage of Deaths from Disease Occurring Among the Poorest 20% of Global Population Malaria 57.9% Childhood Diseases 55.0% Diarrheal Diseases 53.2% Perinatal Conditions 45.0% Tuberculosis 44.4% Maternal Conditions 43.2% Respiratory Infections 42.6% HIV/AIDS 41.8% Weighted Average 48.6% % Deaths

13. Interventions

14. Estimated Cost of Malaria Control in an Endemic Area: One Million People, One Round of Residual House Spraying

15. Estimated Cost of Malaria Control: One Million People, One Full-dose Treatment, 1999

16. Successes

17. Successes • 1899, (large scale) demonstration of successful Anopheline control in Cuba: antilarval and adult measures (large-scale) • 1899–1914, multiple demonstrations of control by reduction of Anopheline larvae and adults • 1899, Sierra Leone (antilarval); Cuba (large-scale); Malaysia (antilarval) • 1904–1914, Panama Canal Zone; control by larviciding, large-scale environmental modification • 1927, elimination of A. albimanus in Barbados (first area-wide success with invading species)

18. Successes (2) • 1935-1939, large-scale control by pyrethrum spraying in South Africa, Netherlands and India • 1939-1957 • 1939-1940, Elimination of invading A.gambiae from Brazil • 1942-1945, A.gambiae eliminated from northern Egypt • 1946-1957, Interruption of transmission by anti-mosquito measures in Cyprus, Sandinia, Guyana, Venezuela and Greece; indoor residual spraying with DDT, a major strategy

19. Successes (3) • 1987-2003 • Multiple projects and programs using insecticide-impregnated bed nets demonstrate overall mortality reduction and decrease in several malaria indices

20. Interventions, Control and Economics

21. Type of ControlVector Control • Environmental modification (urban)* • Chemical and biological larvicides* • Indoor residual insecticide spraying* • Outdoor residual insecticide spraying *costly and effective

22. Type of ControlPersonal protection (2) • Insecticide–impregnated materials: nets, curtains, clothing* • House screening • House location • Repellents • Fumigants * Shown cost effective for low-income countries

23. Type of ControlAntiplasmodial (3) • Patient management: early diagnosis, treatment, referral, education • Chemoprophylaxis • Intermittent treatment (pregnancy)* • Radical therapy for relapses (P.vivax, P.ovale) * cost effective

24. Type of ControlSocial Action • Mobilization of individual, family, community • Health education Management Effectiveness • Health systems effectiveness (quality), efficiency • Leadership, planning, policies, strategies, tactics • Surveillance • Monitoring and evaluation

25. Research Questions

26. Research Agenda • Pathogenesis • Drug development • Vaccine development • Diagnostics • Clinical and community-based trials • Entomology

27. Research Agenda (2) • Clinical issues • anemia • neurologic and cognition • pregnancy-related • Health services delivery • Social, legal, ethical

28. Controversies

29. Controversies • Drugs • Combination artemisinin-based compounds for treatment • Chemoprophylaxis for high risk persons • Burden • Malaria as a cause or risk-factor (co-morbidity) • Cognition and developmental issues

30. Controversies (2) • Transmission • Cost-effective vector control approaches in urban and rural areas • Impregnated materials, how to improve and make the social standard • Basic research • Immunologic, genetic

31. Malaria, Annual WHO Estimates, 1997

32. Malaria in Sri Lanka Plasmodium vivax Plasmodium falciparum

33. 100 % Plasmodium vivax 10 : : 1 0.000 0.01 0.1 1.0 10.0 0.001 Total Annual Malaria Incidence Rate (%)

34. More Southerly, more tropical More Northerly, more temperate 100 % Plasmodium vivax 10 : : 1 0.000 0.01 0.1 1.0 10.0 0.001