Chapter 29 Spatial Patterns of Health and Disease

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Chapter 29 Spatial Patterns of Health and Disease
2
Foot-and-mouth disease

• acute infectious viral disease causing fever,
  followed by the development of vesicles
  (blisters)
• affects cattle, sheep, pigs, and goats and other
  cloven-hooved animals
• airborne spread of the virus and occur in the
  salviva, exhaled air, milk and dung
• Heat, sunshine and disinfectants will destroy the
  virus

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Foot-and-Mouth Disease
Egypt8 Georgia1 Greece 14 Turkey138
UK 2443 France 2 Ireland 1 Netherlands 18
S. Korea15,4/2000 Japan 3, 5/2000 Mongolia 3,
5/2000
Iran455 Kuwait22 Saudi Arabia200 Kazarkstan11
Russia1 Tajikistan2
Malaysia 3, 3/2000 Phillippines 732 Taiwan 5,
2/2000
Brazil54, 10/2000 Peru 47, 10/2000 Argentina
1 Uruguay , 10/2000
Malawi1, 5/2000 Namibia 1, 8/2000 Swaziland 2,
12/2000 Zambia 5, 7/2000
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Introduction

• 16 babies born in 90s were underweight , in
  poorer countries and millions do not survive 1st
  bday.
• In US, the biggest problem - Obesity
• Medical Geography -study of health in
  geographic context.
• Contagious disease, location of hospital and
  environmental relationship between disease and
  demographic distribution

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Malnutrition and Child Mortality

• Kwashiorkor - from protein-deficiency is
  directly related to child mortality rate. A
  malnutrition, not undernutrition, after stopping
  the breast feeding, child was put in a starchy
  diet.
• Marasmus - lack of protein and calories, bony
  thin body, huge eyes

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Infant Mortality Rates (IMR)

• Death during the first year.
• Key factor - the health of the mother.
• Other factors - poor sanitation, improperly
  weaned, dont know how to deal with diarrhea.
• Map shows the relationship be/w social disorder
  and high IMRs, Highest IMR in Sierra Leone
  (195/1000)
• Low IMRs - Japan (no other ethnic variations),
  Singapore, Sweden
• US - various distribution within country.
• In 90s, 25 countries with 100 or higher IMRs, 8
  had rates gt 125/1000, 1 in 8.

IMR in the US
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Life Expectancy
4 yr in Europe, East Asia 3 in Subsaharan
Africa 7 in S Am, 6 in N Am 14 in Russia
Women outlive men
World 68/64 India - 59/59 US-79/73 Japan,Taiwan,
S Korea all high China -72/68
Women/Men
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Life Expectancy

• It might reach 85 yrs by the early 21st century,
  and
• A trend of continued increase in life exp in
  poorer countries
• Larger number of old people in the population, 9
  (500 million) of the world pop - gt60, by 2030 16
  (1.5 billion)
• In W Europe, 1/5 pop are 60, by 2030, 1/3 are
  60
• Young be more productive, taxed more to support
  old.

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Major Types of Diseases
Infectious-65 of human illnesses, eg Malaria
Chronic/Degenerative- Cancer/heart diseases
Genetic or Inherited- Homophilia,
sickle-cell anemia
Epidemic - outbreak of disease in a
region Pandemic - outbreak spreads around the
world Endemic- mononucleosis in campus (carried
by some people without knowing having it)
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How Diseases Spread
Smaller than bacteria, causing measles,
influenza, polio, and maybe certain types of
cancer
Agents
Bacteria
Viruses
Others
Reservoir - large amount of hosts
Not mutually exclusive
Vectored diseases
Nonvectored diseases
Vehicles
Agents
Water, food, feces
Host1
Host2
Host2
Host1
- common cold, measles, venereal diseases and
mononucleosis
House pets, mosquitoes, flies, worms, snails,
ticks
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Malaria Vectored Disease

• Occurs throughout the world, except in higher
  latitude and drier environment
• Not only human being, monkeys, rats, birds and
  snakes are infected too.
• Three African mosquitoes as vectors.
• Major factor in infant and child mortality
• Abandoned ancient fertile lands could have been
  due to the spread of malaria.
• Symptoms - recurrent fever and chills, anemia and
  enlarged spleen
• 1955 WHO launched a program against malaria,
  successfully made Sri Lanka free of malaria (with
  DDT, carcinogen)
• Genetic engineered mosquitoes to replace A.
  gambiae)

12
Yellow Fever

• In tropical and near-tropical areas (in S America
  and Africa)
• Transmitted by mosquitoes carrying virus
• Symptoms - high temp, headache, backache and
  vomiting, jaundice and deposition of bile pigment
  colors make eyes and skin yellow
• Figures 29-3, 29-4

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Sleeping Sickness
Infected Host people, livestock
Symptoms Human -fever, followed by swelling of
the lymph nodes, spread into brain and spinal
cord producing the lethargy and
listlessness Animal - sick animal die within a
year of infection
trypanosome
TSETSE
Potential Host people, livestock
Reservoir (wild animal)
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Schistosomiasis - bilharziaFigure 28-8

• A debilitating disease,transmitted by freshwater
  snails which sends the infected larva into still
  water and penetrates the skin and then, the eggs
  wreak havoc in the liver and other organs.
• Construction of dams provided environments for
  the snails.

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West Nile virus

• Summer of 1999, seven people died and more than
  60 became infected by the virus, which can cause
  lethal brain disease.
• transmitted via mosquito, is primarily a bird
  disease, which caused more than 10,000 crows died
  last year.
• Birds can fly 300 miles/day, there is no safe
  place in the US.
• virus in the US is genetically related to strains
  found in the Middle East
• Symptoms - mild inflammation of the brain, fever,
  headaches, body aches, skin rash and swollen
  lymph glands

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Nonvectored Infectious Diseases1 - Cholera

• Cholera - symptomsdiarrhea and dehydration, an
  ancient disease in India until 19th century
• 1816 spread to China, Japan, East Africa and
  Mediterranean Europe
• 1826 to 1837, second pandemic struck
• 1842 to 1862, cholera crossed the Atlantic and
  attacked N Am. (reached New Orleans and New York
  first)
• Recent cases Naples, Italy in 1972, late 90s in
  Africa, 29 countries affected.
• Cholera vaccine effective only for 6 months

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2 - Influenza

• Causes 20,000 death each year in US.
• Once started, inhaling the airborne virus will
  cause influenza. Originally from Chinese
  influenza A
• In 1997, new strain of influenza broke out in
  Hong Kong

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The Life Cycle of a New Strain of Influenza Virus
New strains spreads to human population
Influenza virus from farmers to pigs
Influenza virus from ducks to pigs
New strain infects farmers
New strain results
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AIDS (Acquired Immune Deficiency Syndrome)Figure
29-13

• Originated from Africa in 1930s and stayed there
  until jet travel, big cities and the sexual
  revolution spread it worldwide
• First recorded AIDS in 1981.
• In Africa, 20.8 million HIV cases in 1998.
• 1/3 babies born to infected women are infected
  with HIV.
• Thailand - the country with most AIDS in
  Southeast Asia
• Urban and rural areas in Africa are affected

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AfricaPeople with HIV/AIDS at the end of 1999
N Africa 220,000 19,000 (new infections in
99) death in 99 13,000 No. of AIDS orphans
15,000
S. Africa 23.3 million 3.8 million (new
infections in 99) death in 99 2.2 million No.
of AIDS orphans 10.7 million
Percentage of deaths by disease, globally and in
Africa
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Effect of HIV/AIDS on life expectancy (1995-2000
projection)
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AIDS in US -1

• Men who have sex with men (MSM)
• The highest HIV infection prevalence rates among
  populations at risk for HIV nationwide were found
  among MSM attending sexually transmitted disease
  (STD) clinics. The median prevalence rate in
  these clinics was 19.3. MSM represented the
  largest proportion (60) of men diagnosed with
  AIDS in 1997. From 1996 to 1997, AIDS incidence
  among MSM declined 18 and deaths declined 49.
• Injecting drug users (IDUs)
• Prevalence in IDUs varies by geographic region
  the highest prevalence rates in surveyed drug
  treatment centers were in the Northeast, the
  South, and Puerto Rico. AIDS incidence and deaths
  among IDUs declined 15 and 45, respectively,
  among men 12 and 33 among women. IDUs diagnosed
  with AIDS represented 24 of AIDS cases in men
  and 47 of those in women in 1997.

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AIDS in US-2

• Racial/ethnic minorities
• HIV prevalence was higher in non-Hispanic blacks
  than in other racial/ethnic groups in most
  populations surveyed.
• Non-Hispanic blacks and Hispanics accounted
  for 47 and 20, respectively, of persons
  diagnosed with AIDS in 1997, the highest
  proportions thus far in the epidemic. From 1996
  to 1997, AIDS incidence and deaths declined in
  all racial/ethnic populations.
• Women
• HIV prevalence among women varies
  geographically in a pattern that reflects the
  prevalence rates among IDUs. From 1996 to 1997,
  AIDS incidence and deaths declined 8 and 32,
  respectively, among women.

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AIDS in US-3

• Youth
• Among youth in the Job Corps, HIV prevalence
  rates were higher in women than in men in the
  same age group. Youth aged 13 through 24 years
  accounted for 4 of AIDS cases reported during
  the 1-year period from July 1997 through June
  1998. They accounted for 15 of HIV infection
  (not AIDS) cases reported during the same period.
  
• Children
• From 1996 to 1997, the number of children
  (under 13 years of age) who were diagnosed with
  AIDS declined 40, principally reflecting the
  continued success of efforts to reduce perinatal
  transmission through promoting voluntary HIV
  testing and zidovudine therapy for pregnant
  HIV-infected women and their infants.

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AIDS in US-4

• Top five states with most reported AIDS cases, in
  1997/98, NY(11,329, 6.23/10,000), CA(6,338,
  1.97/10,000), FL(5,489, 3.77/10,000), TX(4,472,
  2.3/10,000), NJ(2,507, 3.12/10,000), and
• TN (694, 1.29/10,000)
• Top five Metro areas with most reported AIDS
  cases NY (8,711), LA(2,248), Houston(1,759),
  Chicago (1,567) and Miami (1562).

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Chronic Disease

• Leading causes of death in the US
• Modernization brought new lifestyles, pressures,
  exposure to new chemicals (preservatives, sugar
  substitutes), we dont know these how these
  affect our health.
• Arteriosclerosis -from high cholesterol and
  sedentary habits of urban life
• Lead-paint cause brain damage

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Genetic Diseases

• Resulted from gene mutations or accidents to the
  chromosomes.
• Mongolism - Down Syndrome mutation in the fetus
  before birth even if both parents are completely
  normal.
• Radiation and viruses may damage a parents
  chromosomes.
• Phenylketonuria occurs mostly among Europeans
  will cause mental retardation.
• Milk allergy galactosemia, not enough enzyme to
  break down milk sugar lactose, need to supply
  calcium and an ancient custom of eating clay,
  called geophagy, especially in West Africa
• Lactose Intolerance are found more often in
  African Americans than white India and China
  have higher rate of lactose intolerance too.

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Down Syndrome

• Cause-an extra chromosome(in 21st chromosome) in
  the fertilized egg creates abnormalities as the
  fetus develops.
• Risk Factors Pregnancy in females under age 16
  or over 35, family history of Down Syndrome,
  Mothers exposure to drugs, radiation, chemicals,
  or infections before pregnancy.
  anmniocentesis procedure to detect this
  syndrome.

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Cancer fact (Figure 29-14)

• Higher rates of breast cancer in the Northeast
  urban areas
• Higher rates of prostate cancer in the Northeast
  and Great Lakes regions, but N Carolina is the
  highest in death rate even with lower incidence
  rate - 1) not getting to a doctor on time 2) Love
  affair with fat in the N Carolina diet. Highest
  in rural black men - twice as likely as whites.
• Higher rates of leukemia in the Midwest,
  especially farmers (plus prostate, and stomach
  cancer) due to the applications of pesticides,
  DDT, 2,4-D

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Breast Cancer

• Long Island - Nassau and Suffolk counties - the
  highest rates of breast cancer in the country.
• White, higher socioeconomic groups, Ashkanazi
  Jewish background
• 30 increase from 1970s to 1990s
• What cause cancer? - Environment, genetic, and
  lifestyles

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Breast Cancer Mortality Rate by county, 1970-94,
white females
Female African Americans Cancer Mortality Rate,
1970-94
Male African American Cancer, 1970-94
Cancer Incidence Rate in Tennessee, 1996
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Cancer in Minorities

• In 2000, about 1,220,100 cancers are expected to
  be diagnosed in the US, and 552,200 Americans are
  expected to die of this disease - American
  Cancer Society
• Black Whites Hisp Asian/Pac Ame Indian
• Incidence Rates(per 100,000)
• 443 403 275 279 153
• Mortality Rates (per 100,000)
• 223 167 105 103 104
• Mortality/Incidence
• 50 41 38 37 68

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Cancer in the U.S.

• Mortality Rate
• Tennessee US
• Female Male Female Male
• 139.6 241.7 142.3 218.3
• Higher cancer death rates of Lung/Bronchus (96.4
  vs 73.4 per 100,000) a 32 more
• Much lower Stomach cancer death rate 5.4 vs 6.5
  per 100,000, a 17 lower rate)

Data from American Cancer Society
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Smoking in the US Population
Tennessee - 26.1, 44th in the country
Lung/Trachea/Bronchus and Pleura, 1970-94, white
males