1 / 29

Malaria: Coming soon to an airport near you!

Malaria: Coming soon to an airport near you!. Tropical Diseases in the Global Village. You too can get tropical diseases without leaving the comfort of your own home. What accounts for the geographic restriction of some diseases? How do diseases move into new areas?

noah
Download Presentation

Malaria: Coming soon to an airport near you!

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. Malaria: Coming soon to an airport near you! Tropical Diseases in the Global Village

  2. You too can get tropical diseases without leaving the comfort of your own home.

  3. What accounts for the geographic restriction of some diseases? • How do diseases move into new areas? • Are tropical diseases really diseases of economic underdevelopment?

  4. Malaria has been with us for a long time DNA evidence mummies 10,000 BC now The A- African variant of G-6-PD may date as far back as 11,760 years ago

  5. When did malaria come to the New World? • with Columbus or the slave trade • no documented blood polymorphisms associated with malaria resistance in the Amerindians, so malaria is recent • Ravenel’s extinction hypothesis: eradication of the original natives of the Caribbean islands and coastal plain was caused by malaria

  6. Did malaria arrive twice? • P. simium in New World monkeys looks like AsianP. vivax • New World P. vivax is distinct from both • DNA • vector specificity

  7. Conclusion: • malaria entered the New World twice • once > stable transmission in monkeys • once > stable transmission in man

  8. How is transmission established? mosquito bite second host bite first host man

  9. Factors that influence transmission mosquito bite second host susceptible vector species bite first host man

  10. Factors that influence transmission mosquito bite second host vector longevity bite first host man

  11. Factors that influence transmission mosquito bite second host biting preferences bite first host man

  12. Factors that influence transmission mosquito bite second host infected reservoir bite first host man

  13. Factors that influence transmission mosquito bite second host available to vector bite first host man

  14. Colonial America • malaria was well established in Connecticut by 1650 • Charleston, SC, was almost abandoned in 1680 because of the intensity of malaria transmission

  15. Eradication in the north • 1900: Staten Island, NY, one in five residents has malaria • 1901: Port Authority gives $50,000 to Alvah Doty to drain the marshes • 1908: Staten Island is malaria-free

  16. Malaria and the New Deal • ecological degradation of major river basins in the South • deforestation • erosion • uncontrolled floods • 1933: 150,000 cases of malaria, 5,000 deaths annually in Tennessee R. basin

  17. TVA: Power and Public Health • 21 dams, 600,000 acres of lakes • mosquito control teams • periodically raise and lower water levels • speed water flow in canals • clear aquatic vegetation • 1942: 50,000 malaria cases annually, 600 deaths

  18. DDT • 1943: widescale aerial application • 1952: malaria eradicated • 1962: Silent Spring

  19. Will malaria return? • reappearance of infected hosts • immigrants from endemic regions • returning military personnel • transmission from a single marine to 35 campers in the California Sierras

  20. Will malaria return? • introduction of new efficient vectors • 1930: Anopheles gambiae introduced into Brazil by a French naval vessel; epidemic malaria, 16,000 deaths • malaria vectors brought to Guam by military aircraft during WWII and Viet Nam war; outbreaks in 1966 and 1969

  21. Airport Malaria: The case for disinsection • between 1969 and 1999 • 26 cases in France • 17 cases in Belgium • 14 cases in the UK • 4 cases in Germany • 4 cases in the US

More Related