Mortality of a disease Dose -number of organisms infecting...

Mortality of a diseaseDose

-number of organisms infecting.-determines likelihood of symptomatic disease.-different dose responses.



Reproductive capacity-some reproduce within humans.-increases # of pathogenic organisms.



Reproductive capacity-some reproduce within humans.-increases # of pathogenic organisms.

Innate pathogenicity.-some disease-causing organisms cause more damage

than others.-type of tissue(s) affected.-metastasis to other tissues.-toxic metabolic products.-immuno-depressers.-this determines an individual human’s likelihood of dying.

Mortality of a diseaseEase of transmission.

-easily-transmitted disease-causing organisms infect more people.

-this determines the population-level mortality risk.

Mortality of a diseaseEase of transmission.

-easily-transmitted disease-causing organisms infect more people.

-this determines the population-level mortality risk.Other factors.

Risk of secondary infection.Individual-level: nutrition, immunocompetency, other

diseases, sex, age, behavior.Population-level: density, hygienic facilities, geography,

treatment availability, group-level behaviors.

Geography of a diseaseHumans are everywhere; thus, the geography of a disease is

usually linked to:-historical factors (where diseases have always been).

e.g., some hemorrhagic fevers.-current biological limitations on disease spread.

e.g., African Trypanosomiasis.-historical and contemporary eradication and control.

e.g., malaria gone from the temperate zone.

Geography of a diseaseHumans are everywhere; thus, the geography of a disease is

usually linked to:-historical factors (where diseases have always been).

e.g., some hemorrhagic fevers.-current biological limitations on disease spread.

e.g., African Trypanosomiasis.-historical and contemporary eradication and control.

e.g., malaria in the temperate zone.Disease transmission mode.

-Directly transmitted: usually more cosmopolitan.e.g., amebiasis, ascariasis, influenza, cholera.

-Vector or intermediate host mediated: usually more restricted.e.g., trypanosomiasis, schistosomiasis.

Geography of morbidity and mortality.Endemic levels of disease: those levels of morbidity and mortality

that are relatively unchanged over long periods of time.-e.g., syphilis in the U.S. (~ 3,000-4,000 new cases per

month).-these are background diseases and part of the normal

health care of most countries.


that are relatively unchanged over long periods of time.

Epidemic levels of disease: a spike in morbidity and mortality beyond the normal endemic upper range.-e.g., African trypanosomiasis in Uganda (250,000 dead in

20 years).-these place huge burdens on health care.


that are relatively unchanged over long periods of time.

Epidemic levels of disease: a spike in morbidity and mortality beyond the normal endemic upper range.

Pandemic levels of disease: a global, or nearly global, spike in morbidity and mortality beyond the normal endemic upper range.-e.g., 1918-1919 influenza pandemic killed 50 million or

more.-these are out of control and usually run their course.

0

0.05

0.1

0.15

0.2

0.25

0.3

AFR AMR Emed Eur SEA Wpac

% Pop

% Deaths

0

0.05

0.1

0.15

0.2

0.25

0.3


% Pop

% Deaths

Regional % of global population and annual deaths

2004 2008

0

0.05

0.1

0.15

0.2

0.25

0.3

Africa Americas Emed European SE Asia W Pac

% Pop

% Deaths

2016

Regional % of global population and annual deaths

0

0.05

0.1

0.15

0.2

0.25

0.3

0.35

0.4

0.45

0.5

World AFR AMR Emed Eur SEA Wpac0

0.05

0.1

0.15

0.2

0.25

0.3

0.35

0.4

0.45

0.5

World AFR AMR Emed Eur SEA Wpac

% of annual deaths in a region due to parasitic and communicable diseases

2004 2008

0

5

10

15

20

25

30

35

40

45

Global Africa Americas Emed European SE Asia W Pac

% of annual deaths in a region due to parasitic and communicable diseases

2016

0

0.05

0.1

0.15

0.2

0.25


Tuberculosis

AIDS

Malaria

Neoplasms

0

0.05

0.1

0.15

0.2

0.25


Tuberculosis

AIDS

Malaria

Neoplasms

% of annual deaths in a region due to tuberculosis, AIDS, malaria, and cancers

2004 2008

0

5

10

15

20

25


TB

AIDS

Malaria

Neoplasms

% of annual deaths in a region due to tuberculosis, AIDS, malaria, and cancers

2016

0

0.02

0.04

0.06

0.08

0.1

0.12

0.14


Respiratory

Birth/maternal

Nutrition

0

0.02

0.04

0.06

0.08

0.1

0.12

0.14


Respiratory

Birth/maternal

Nutrition

% of annual deaths in a region due to major correlates of poverty

2004 2008

0

5

10

15

20

25

30


% of annual deaths in a region due to major correlates of poverty

2016: Resp, Birth/Mat, Nutrition

0

0.1

0.2

0.3

0.4

0.5

0.6

High Umid Lmid Low

% Pop

% Deaths

% of global population and annual deaths by national wealth

2004 2008

0

0.1

0.2

0.3

0.4

0.5

0.6

High Umid Lmid Low

% Pop

% Deaths

0

0.05

0.1

0.15

0.2

0.25

0.3

0.35

0.4

0.45

High U Mid L Mid Low

% Pop

% Deaths

% of global population and annual deaths by national wealth

2016

0

0.05

0.1

0.15

0.2

0.25

0.3

0.35

0.4

World High Umid Lmid Low0

0.05

0.1

0.15

0.2

0.25

0.3

0.35

0.4

World High Umid Lmid Low

% of annual deaths due to parasitic and communicable diseases by national wealth

2004 2008

0

5

10

15

20

25

30

35

40

Global High U Mid L Mid Low

% of annual deaths due to parasitic and communicable diseases by national wealth

2016

0

0.05

0.1

0.15

0.2

0.25

0.3

High Umid Lmid Low

Tuberculosis

AIDS

Malaria

Neoplasms

0

0.05

0.1

0.15

0.2

0.25

0.3

High Umid Lmid Low

Tuberculosis

AIDS

Malaria

Neoplasms

% of annual deaths due to tuberculosis, AIDS, malaria, and cancers by national wealth

2004 2008

0

5

10

15

20

25

30


TB

AIDS

Malaria

Neoplasms

% of annual deaths due to tuberculosis, AIDS, malaria, and cancers by national wealth

2016

0

0.02

0.04

0.06

0.08

0.1

0.12

0.14

High Umid Lmid Low

Respiratory

Birth/maternal

Nutrition

0

0.02

0.04

0.06

0.08

0.1

0.12

0.14

High Umid Lmid Low

Respiratory

Birth/maternal

Nutrition

% of annual deaths due to major correlates of poverty by national wealth

2004 2008

0

5

10

15

20

25

30


% of annual deaths due to major correlates of poverty by national wealth

2016

Top 10 countries for tuberculosis deaths (2008)

Timor: 12.7%Bangladesh: 7.1%

Top 10 countries for tuberculosis deaths (2016)

Timor: 16.7%Mozambique: 7.1%

Top 10 countries for AIDs deaths (2008)

Zimbabwe: 50.5%Mozambique: 20.6%

Top 10 countries for AIDS deaths (2016)

Lesotho 33.2%Kenya 12.6%

Top 10 countries for malaria deaths (2008)

Burkina Faso: 16.1%Nigeria: 11.1%

Top 10 countries for malaria deaths (2016)

Burkina Faso 13.4%C. Afr. Rep 6.2%

0

0.05

0.1

0.15

0.2

0.25

0.3

0‐4 5‐14 15‐29 30‐44 45‐59 60‐69 70‐79 80+

Neoplasms

Chaga's

% of deaths caused by a disease occurring in different age classes

Increase with age


0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1

0‐4 5‐14 15‐29 30‐44 45‐59 60‐69 70‐79 80+

Measles

malaria

Decrease with age


0

0.05

0.1

0.15

0.2

0.25

0.3

0.35

0.4

0.45

0.5

0‐4 5‐14 15‐29 30‐44 45‐59 60‐69 70‐79 80+

AIDS

Hep B

Tuberculosis

High in mid ages


0

0.1

0.2

0.3

0.4

0.5

0.6

0‐4 5‐14 15‐29 30‐44 45‐59 60‐69 70‐79 80+

Diarrhea

Upper resp

Low in mid ages

0

2

4

6

8

10

12

14

2009 2008 2007 2006 2005 2004 2003 2002 2001 2000

Canada

United States ofAmerica

# of new cases of cholera by country

Low and imported


0

200

400

600

800

1000

1200

1400

1600

1800

2000

2009 2008 2007 2006 2005 2004 2003 2002 2001 2000

Burundi

China

Low and endemic


0

1000

2000

3000

4000

5000

6000

2009 2008 2007 2006 2005 2004 2003 2002 2001 2000

Uganda

Ghana

High and endemic


0

10000

20000

30000

40000

50000

60000

70000

80000

2009 2008 2007 2006 2005 2004 2003 2002 2001 2000

Liberia

Democratic Republic of theCongo

Malawi

Zimbabwe

Epidemic

Life expectancy at birth

Zimbabwe Canada1990: 60.8 1990: 77.12009: 49.0 2009: 81.2

Lesotho United States1990: 60.1 1990: 75.32009: 48.2 2009: 78.5

Disease Name Etiological Agent Mode of Transmissionto Humans

Life Cycle Geographical Distribution

Pathology and Mortality

Yellow Fever RNA virus Bite of mosquito Coincident with mosquito vector; can be epidemic

Tropical and subtropical Africa and South America

Liver damage and bleeding

Smallpox Variola spp. (virus) Airborne and fluid-borne

N/A Worldwide Skin lesions; invasion of visceral organs

Influenza Influenza viruses Airborne and fluid-borne

Seasonal outbreaks, usually most intense in winter

Worldwide Cellular destruction in respiratory tract

AIDS Human immunodeficiency Virus

Sexual intercourse; exchange of fluids

N/A Worldwide Destruction of T-cells of immune system leading to immunodeficiency

Plague Yersinia pestis(bacterium)

Bite of flea associated with plague-infested rodents

Coincident with rodent-human interactions; can be epidemic

Worldwide Destruction of cells of lymph and other areas

Cholera Vibrio cholerae(bacterium)

Ingestion of bacteria in contaminated water or food

Seasonal epidemics, with semi-global pandemics yearly

Worldwide Destruction of intestinal lining.

Tuberculosis Mycobacterium tuberculosis(bacterium)

Airborne and fluid-borne

N/A Worldwide, with epidemics in poor countries, especially in Africa and Asia

Destruction of lung tissue; tubercle formation; blood involvement

Leprosy Mycobacterium leprae (bacterium)

Airborne in droplets of fluid

N/A Worldwide, with epidemics in Africa, Asia, and S. America

Destruction of nerve cells and surrounding tissues

Syphilis Treponema pallidum(bacterium)

Sexual intercourse N/A Worldwide Chancres and sores externally; neurological damage

Disease Name Etiological Agent Mode of Transmissionto Humans

Life Cycle Geographical Distribution

Pathology and Mortality

Malaria Plasmodium species (protozoa)

Bite of female anopheline mosquito infected with Plasmodium spp.

Coincident with life cycle of local mosquitoes; can be epidemic

Mostly tropical and subtropical Africa, S. America, Asia, and Atl./Pac. Islands

RBC destruction (anemia); neurological damage; kidney damage

Kala azar Leishmania donovoni(protozoa)

Bite of sandfly, Phlebotomus

Coincident with life cycle of local sandflies; can be epidemic

Mostly tropical and substropical, esp. India, S. America, and Middle East

Destruction of cells in liver and spleen causing eventual rupture of these organs

African Sleeping Sickness

Trypanosoma species (protozoa)

Bite of tsetse fly, Glossina

Coincident with life cycle of tsetse flies; can be epidemic

Limited to African continent by range of tsetse fly vectors

Destruction of neurological and lymph tissues

Schistosomiasis Schistosoma species (trematodes)

Invasion of skin by cercariae shed from snail

Eggs passed via feces/urine; snail infected; cercariae released from snail

Mostly tropical and subtropical, with foci in Africa, S. America, and SE Asia

Destruction of intestinal and urinary tissues; other tissues may be destroyed

Hookworm disease Necator americanusor Ancylostomaduodenale (nematode)

Invasion of skin by larvae in soil

Eggs passed via feces in soil; juveniles develop in soil

Worldwide, but abundant only in warm, moist areas

Anemia due to ingestion of blood; tissue damage of intestine

Mortality of a disease Dose -number of organisms infecting...

Documents

Transcript of Mortality of a disease Dose -number of organisms infecting...