1. Malaria Facts Where malaria is common the average life span is 30 YOA. This is not all due to malaria but malaria and trypanosomiasis do play their part!

2. Malaria Facts Where malaria is common the average life span is 30 YOA. This is not all due to malaria but malaria and trypanosomiasis do play their part! Malaria has protected Western Africa from European colonization!

3. Malaria has Been Significant Enough to Make the World Different! Being sent to Gambia, Serra Leon, etc. was considered a death sentence because of the probability of contracting malaria!

4. Malaria has Been Significant Enough to Make the World Different! Being sent to Gambia, Serra Leon, etc. was considered a death sentence because of the probability of contracting malaria! 1880 was when Plasmodium was fist discovered.

5. Malaria has Been Significant Enough to Make the World Different! Being sent to Gambia, Serra Leon, etc. was considered a death sentence because of the probability of contracting malaria! 1880 was when Plasmodium was fist discovered. 1897: the vector host was discovered by Ronald Ross. But it did not matter since there was no attempt to control it!

6. Malaria in History Ancient references –China, Assyria, India –500 BC Hippocrates gives first clinical description

7. Malaria in History Ancient references –China, Assyria, India –500 BC Hippocrates gives first clinical description Historical Impacts –413 BC Fall of Greek empire –323 BC Alexander the Great died of malaria –The Roman Empire: Malaria is generally considered to have played a role in the decline of Rome, a city located in marshland, where malaria is transmitted

8. History 1800’s 20-40% of people hospitalized in New Orleans had malaria

9. History 1800’s 20-40% of people hospitalized in New Orleans had malaria 1861-1865 Civil War. Savannah, GA 878 men had 3313 cases of malaria in a 14 month period.

10. History 1800’s 20-40% of people hospitalized in New Orleans had malaria 1861-1865 Civil War. Savannah, GA 878 men had 3313 cases of malaria in a 14 month period. 1880 Plasmodium discovered as etiological agent

11. History 1800’s 20-40% of people hospitalized in New Orleans had malaria 1861-1865 Civil War. Savannah, GA 878 men had 3313 cases of malaria in a 14 month period. 1880 Plasmodium discovered as etiological agent 1900’s Sir Ronald Ross discovers mosquitoes are vectors

12. History 1800’s 20-40% of people hospitalized in New Orleans had malaria 1861-1865 Civil War. Savannah, GA 878 men had 3313 cases of malaria in a 14 month period. 1880 Plasmodium discovered as etiological agent 1900’s Sir Ronald Ross discovers mosquitoes are vectors 1930’s malaria diminished in U.S. except for southeast. Conversion of swamp to agriculture.

13. 18821912 1934

16. World War II. In 1942, 2678 cases from 1,000 men; Ran out of drug for treatment. History

17. Gen. Douglas MacArthur in May 1943: "Doctor," he said, "this will be a long war if for every division I have facing the enemy I must count on a second division in hospital with malaria and a third division convalescing from this debilitating disease!" The general was not at all worried about defeating the Japanese, but he was greatly concerned about the failure up to that time to defeat the Anopheles mosquito. History

18. Lost five times more men to malaria than in Battle!

19. History Lost five times more men to malaria than in Battle! Brought about chemical insecticides. –DDT was a result of WWII –And a few year later there were only 50/1000

20. History Lost five times more men to malaria than in Battle! Brought about chemical insecticides. –DDT was a result of WWII –And a few year later there were only 50/1000 So after the war there was a false hope of eradicating malaria from the world!

21. 1946. WHO initiates program to “eradicate malaria”. History

22. 1946. WHO initiates program to “eradicate malaria”. 1961: A parasitology textbook is quoted as saying “with present prospects, malaria WILL soon be treated as an uncommon/non-existent disease. History

23. 1946. WHO initiates program to “eradicate malaria”. 1961: A parasitology textbook is quoted as saying “with present prospects, malaria WILL soon be treated as an uncommon/non-existent disease. 1970. Malaria decreased dramatically. History

24. Eradication of Malaria So why did the campaign fail? 1) Insecticides (DDT) –Environmental damage!

25. Pesticide Resistance Rapid Reproduction Selection DDT

26. Pesticide Resistance Rapid Reproduction Selection

27. Eradication of Malaria 2) Plasmodium –Wide use of chloroquine has led to drug resistant strains!

28. Eradication of Malaria 3) Social/Political Reasons –Emerging nations in Africa were trying to be free from external (Western European nations) domination; much of the monetary resources stopped flowing in!

29. Genetic resistance to Plasmodium 2 examples There are some general genotypes that are resistant to malaria

30. Duffy Blood Group Noticed in military groups in Vietnam. African Americans had less severe cases or no cases of malaria!

31. Genetic Resistance Plasmodium vivax Duffy blood groups –Proteins on cell surface –3 alleles A Dominant B Dominant y recessive A = B = y = no proteins

32. Genetic Resistance Plasmodium vivax Duffy blood groups –Proteins on cell surface –3 alleles A Dominant B Dominant y recessive A = B = y = no proteins AB yy AA BB Ay By

33. Genetic Resistance yy genotype has advantage –P. vivax malaria resistance –Only advantageous if P. vivax malaria endemic 40% people of W. African decent 0.1% people of non-African decent P. vivax keeps the allele common in Africa.

34. Genetic Resistance Sickle celled anemia Codominant trait (Allele “A” and “B”) –AA have sickle celled anemia –AB have both types of cells Sickle cells don’t support species of Plasmodium well. Resistance to infection

35. Genetic Resistance AA selected against –Sickle celled anemia AB selected for –Both sickle and normal cells BB selected against –Normal cells If malaria not endemic, what alleles will be selected for? Against? Allele for sickle cells maintained in the population even though strongly disadvantageous to have both alleles.

36. Genetic Resistance

37. Sickle Celled Anemia In the US, 10% of African Americans have this allele!

38. Other forms of Resistance to Malaria Babies get antibodies from their moms breast milk; they are protected until weaned. Once weaned becomes susceptible again!

39. What you need to have malaria spread within a population!

40. Epidemiological Models Infected People Mosquitoes Uninfected People contact Habitat Climate Food Source of Plasmodium Source of New Hosts Habitat Behavior

41. Breaking the Chain Infected People Mosquitoes Uninfected People contact Habitat Climate Food Source of Plasmodium Source of New Hosts Habitat Behavior

42. Eliminating Mosquitoes Mosquito Life Cycle

43. Eliminating Mosquitoes

44. Destroy habitat Insecticides Biological control

45. Eliminating Mosquitoes Destroy habitat Insecticides Biological control Why don’t these methods work?

46. Pesticide Resistance Rapid Reproduction Natural selection

47. Getting rid of the source of Plasmodium

48. Drug treatment Transgenic mosquitoes

49. Getting rid of the source of Plasmodium Drug treatment Transgenic mosquitoes Why don’t these work?

50. Getting rid of the source of Plasmodium Drug treatment Transgenic mosquitoes Why don’t these work? –Availability of drugs Money Medical staff –Recrudescense –Drug resistance –Reservoir hosts? –Transgenic mosquitoes not a reality –Expensive

51. How can we protect the uninfected population? Vaccines Prophylactic drugs

52. How can we protect the uninfected population? Vaccines Prophylactic drugs Why don’t these work?

53. How can we protect the uninfected population? Vaccines Prophylactic drugs Why don’t these work? –Vaccines unsuccessful –Prophylactic drugs expensive –Prophylactic drugs unpleasant

54. How can we prevent contact between people and mosquitoes? Insecticides Mosquito nets Long clothing Behavior Avoid mosquito habitat Screens on houses

55. How can we prevent contact between people and mosquitoes? Insecticides Mosquito nets Long clothing Behavior Avoid mosquito habitat Screens on houses Why don’t these work?

56. How can we prevent contact between people and mosquitoes? Insecticides Mosquito nets Long clothing Behavior Avoid mosquito habitat Screens on houses Why don’t these work? –Money –Availability of materials –Human behavior difficult to change

57. "Everything about malaria is so molded by local conditions that it becomes a thousand epidemiological puzzles." Hackett (1937)

58. Roll Back Malaria (RBM) Strategy Early diagnosis and prompt treatment

59. Roll Back Malaria (RBM) Strategy Early diagnosis and prompt treatment Prevention –insecticide-treated materials –vector control measures indoor spraying larvicide environmental management

60. Roll Back Malaria (RBM) Strategy Early diagnosis and prompt treatment Prevention –insecticide-treated materials –vector control measures indoor spraying larvicide environmental management Prevention of malaria in pregnancy

61. Roll Back Malaria (RBM) Strategy Early diagnosis and prompt treatment Prevention –insecticide-treated materials –vector control measures indoor spraying larvicide environmental management Prevention of malaria in pregnancy Monitoring for epidemics –Rapid response

62. Roll Back Malaria (RBM) Strategy Early diagnosis and prompt treatment Prevention –insecticide-treated materials –vector control measures indoor spraying larvicide environmental management Prevention of malaria in pregnancy Monitoring for epidemics –Rapid response New methods and tools

63. Roll Back Malaria (RBM) Strategy Early diagnosis and prompt treatment Prevention –insecticide-treated materials –vector control measures indoor spraying larvicide environmental management Prevention of malaria in pregnancy Monitoring for epidemics –Rapid response New methods and tools Improvement in existing tools through research and development

64. Roll Back Malaria (RBM) Strategy Early diagnosis and prompt treatment Prevention –insecticide-treated materials –vector control measures indoor spraying larvicide environmental management Prevention of malaria in pregnancy Monitoring for epidemics –Rapid response New methods and tools Improvement in existing tools through research and development Coordinated action through establishing partnerships that utilize an optimal mix of measures adapted to local situations.