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Monroe L. Weber-Shir k S chool of Civil and Environmental Engi neering Public Health Implications of Water Supply Improvements Did Environmental Engineers save the world?
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Monroe L. Weber-Shirk S chool of Civil and Environmental Engineering Public Health Implications of Water Supply Improvements Did Environmental Engineers.

Dec 19, 2015

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Page 1: Monroe L. Weber-Shirk S chool of Civil and Environmental Engineering Public Health Implications of Water Supply Improvements Did Environmental Engineers.

Monroe L. Weber-Shirk

School of Civil and

Environmental Engineering

Public Health Implications of Water Supply ImprovementsPublic Health Implications of Water Supply Improvements

Did Environmental Engineers save the world?

Page 2: Monroe L. Weber-Shirk S chool of Civil and Environmental Engineering Public Health Implications of Water Supply Improvements Did Environmental Engineers.

Review: Public Health Implications of Water Supply Improvements

Review: Public Health Implications of Water Supply Improvements

The life expectancy transitionThe role of water supply, sanitation, and

hygieneIn the Global North a century agoIn the Global South

The U5MR connectionExposure Routes: breaking the cyclePathogens in the loopImplications for successful interventions

0

20

40

60

80

100

1650 1700 1750 1800 1850 1900 1950 2000 2050

Year

life

ex

pec

tan

cy (

yea

rs)

Pre-agrarian

Poor-agrarian Early C

ities

Modern Cities

The transition

0

5

10

15

20

25

30

35

1900 1910 1920 1930 1940 1950

year

deat

hs p

er 1

00,0

00

0

0.05

0.1

0.15

0.2

0.25

0.3

0 2000 4000 6000 8000 10000

GNP per person$1991, purchasing power parity

U5M

R

Human excreta

Animal excreta

Dry sanitation involving reuse

Waterborne sewage

Non recycling latrines

Soil

Surface water

Ground water

Food

Drinking water

Oral

Land application

Hands

Crops

Flies

Water

washing

Mean = life expectancy

0

5000

10000

15000

20000

25000

0 2 8 13 18 23 28 33 38 43 48 53 58 63 67 72 77 82 89

Mean age at death in interval (nearest year)

Num

ber

of d

eath

s / y

r (f

or 1

0000

0 bi

rths

/yr) Mean = life expectancyMean = life expectancy

0

5000

10000

15000

20000

25000

0 2 8 13 18 23 28 33 38 43 48 53 58 63 67 72 77 82 89

Mean age at death in interval (nearest year)

Num

ber

of d

eath

s / y

r (f

or 1

0000

0 bi

rths

/yr)

Page 3: Monroe L. Weber-Shirk S chool of Civil and Environmental Engineering Public Health Implications of Water Supply Improvements Did Environmental Engineers.

0

20

40

60

80

100

1650 1700 1750 1800 1850 1900 1950 2000 2050

Year

life

ex

pec

tan

cy (

yea

rs)

Life Expectancy Transition(Global North)

Life Expectancy Transition(Global North)

Only intended to indicate trends!

Pre-agrarian

Poor-agrarian

Ear

ly C

ities

Modern Cities

The transition

Who gets the credit?

Page 4: Monroe L. Weber-Shirk S chool of Civil and Environmental Engineering Public Health Implications of Water Supply Improvements Did Environmental Engineers.

Life expectancy in EnglandLife expectancy in England

From family reconstitution

(mostly rural)

From vital registration

males females

0

10

20

30

40

50

60

70

80

90

1600 1650 1700 1750 1800 1850 1900 1950 2000

Year

Lif

e ex

pec

tan

cy

Page 5: Monroe L. Weber-Shirk S chool of Civil and Environmental Engineering Public Health Implications of Water Supply Improvements Did Environmental Engineers.

Life Expectancy in SwedenLife Expectancy in Sweden

0

10

20

30

40

50

60

70

80

90

1750 1800 1850 1900 1950 2000

life

ex

pe

cta

nc

y a

t b

irth

males females

Page 6: Monroe L. Weber-Shirk S chool of Civil and Environmental Engineering Public Health Implications of Water Supply Improvements Did Environmental Engineers.

0

20

40

60

80

100

1650 1700 1750 1800 1850 1900 1950 2000 2050

Year

life

expe

ctan

cy (

year

s)Life Expectancy Transition

(Global South)Life Expectancy Transition

(Global South)

Based on no data! (just my overly generalized thoughts…) Increase in life expectancy is occurring later than in the

North Cities are generally benefiting sooner Huge variation between and within countries

Pre-agrarian Poor-agrarian

Wealthy

Poor

Page 7: Monroe L. Weber-Shirk S chool of Civil and Environmental Engineering Public Health Implications of Water Supply Improvements Did Environmental Engineers.

Distribution of deaths by age at death with mean = 75 years

Distribution of deaths by age at death with mean = 75 years

0

5000

10000

15000

20000

25000

30000

0 3 8 13 18 23 28 33 38 43 48 53 58 63 68 73 78 82 91

Mean age at death in interval (nearest year)

Nu

mbe

r of

dea

ths

/ yr

(for

100

000

bir

ths/

yr) Disease that takes a lifetime to kill (high

blood pressure, tobacco, cholesterol…)

Page 8: Monroe L. Weber-Shirk S chool of Civil and Environmental Engineering Public Health Implications of Water Supply Improvements Did Environmental Engineers.

Distribution of deaths by age at death with mean = 35 years

Distribution of deaths by age at death with mean = 35 years

Mean = life expectancy

0

5000

10000

15000

20000

25000

0 2 8 13 18 23 28 33 38 43 48 53 58 63 67 72 77 82 89

Mean age at death in interval (nearest year)

Nu

mbe

r of

dea

ths

/ yr

(for

100

000

bir

ths/

yr)

Why are these people dying

young?

Page 9: Monroe L. Weber-Shirk S chool of Civil and Environmental Engineering Public Health Implications of Water Supply Improvements Did Environmental Engineers.

Mortality due to leading factorsMortality due to leading factors

Water, Sanitation, Hygiene

Inadequate food

Air pollution

Page 10: Monroe L. Weber-Shirk S chool of Civil and Environmental Engineering Public Health Implications of Water Supply Improvements Did Environmental Engineers.

Burden of disease due to leading risk factors

Burden of disease due to leading risk factors

DALY:_______________________Disability-adjusted life year

Our focus in this course…

Page 11: Monroe L. Weber-Shirk S chool of Civil and Environmental Engineering Public Health Implications of Water Supply Improvements Did Environmental Engineers.

The role of Water Supply, Sanitation, and Hygiene

The role of Water Supply, Sanitation, and Hygiene

Contribute significantly to mortality and morbidity on the global level

Have an enormous influence on U5MR (under 5 mortality rate)

But why are these 3 items grouped together?What is the effect of safe drinking water?Let’s examine the role of safe drinking water in the life

expectancy transition

Page 12: Monroe L. Weber-Shirk S chool of Civil and Environmental Engineering Public Health Implications of Water Supply Improvements Did Environmental Engineers.

Mills-Reincke PhenomenonMills-Reincke Phenomenon

‘…. the purification of polluted public water-supplies reduces the general death-rate much more than it would be reduced by the saving of deaths from the commonly recognized water-borne disease, typhoid fever and Asiatic cholera alone.’

Sedgwick WT, MacNutt JS. On the Mills-Reincke phenomenon and Hazen's theorem concerning the decrease in mortality from diseases other than typhoid fever following the purification of public water-supplies. J.Infect.Dis. 1910; 7 : 489-564.

This is the “Environmental Engineers Saved the World” Hypothesis.

Page 13: Monroe L. Weber-Shirk S chool of Civil and Environmental Engineering Public Health Implications of Water Supply Improvements Did Environmental Engineers.

U.S. Typhoid Fever MortalityU.S. Typhoid Fever Mortality

0

5

10

15

20

25

30

35

1900 1910 1920 1930 1940 1950

year

deat

hs p

er 1

00,0

00

Chlorination was begun in Jersey City, N.J., in 1908. Adoption by other cities and towns across the US soon followed and resulted in the virtual elimination of waterborne diseases such as cholera, typhoid, dysentery and hepatitis A

Chlorination begins in Jersey City

Chlorine saved the day

Page 14: Monroe L. Weber-Shirk S chool of Civil and Environmental Engineering Public Health Implications of Water Supply Improvements Did Environmental Engineers.

Chlorine Cause and Effect:What else would you like to know…

Chlorine Cause and Effect:What else would you like to know…

What was the mortality rate before the introduction of chlorine?

When did other cities adopt chlorination?How did the mortality rate change for cities

when they began chlorinating?What other changes were occurring during

the 1900s that may have influenced mortality?

Page 15: Monroe L. Weber-Shirk S chool of Civil and Environmental Engineering Public Health Implications of Water Supply Improvements Did Environmental Engineers.

Typhoid Fever Mortality Baden, Germany 1855 to 1881

Typhoid Fever Mortality Baden, Germany 1855 to 1881

020406080

100120140160

1850 1860 1870 1880 1890

year

dea

thra

te p

er 1

00

,00

0

Typhoid decreased here before water supply improvements!

Page 16: Monroe L. Weber-Shirk S chool of Civil and Environmental Engineering Public Health Implications of Water Supply Improvements Did Environmental Engineers.

Typhoid fever death rate per 100,000 inhabitants per year in Albany, NY

Typhoid fever death rate per 100,000 inhabitants per year in Albany, NY

0

20

40

60

80

100

120

140

1890 1895 1900 1905 1910 1915 1920 1925

year

Dea

th ra

te p

er 1

00,0

00

Death rate per 100,000

Introduction of filtration

Introduction of disinfection

Flooding of the filtering unit

Increased chlorination

Typhoid decrease coincided with water filtration!

Page 17: Monroe L. Weber-Shirk S chool of Civil and Environmental Engineering Public Health Implications of Water Supply Improvements Did Environmental Engineers.

U.S. population supplied with filtered water

U.S. population supplied with filtered water

0%

10%

20%

30%

40%

50%

1880 1890 1900 1910 1920

year

perc

ent o

f urb

an p

opul

atio

n re

ceiv

ing

filte

red

wat

er slow

rapid

total

0

5

10

15

20

25

30

35

1900 1910 1920 1930 1940 1950

year

deat

hs p

er 1

00,0

00Reduction in typhoid might be correlated with installation of filters

Typhoid

Page 18: Monroe L. Weber-Shirk S chool of Civil and Environmental Engineering Public Health Implications of Water Supply Improvements Did Environmental Engineers.

Correlation between Water Supply Improvements and Public Health?Correlation between Water Supply Improvements and Public Health?

A causal link?FiltrationChlorination

Delayed response?No link?US 1900 – 1940

interpretationYour call (homework!)

Page 19: Monroe L. Weber-Shirk S chool of Civil and Environmental Engineering Public Health Implications of Water Supply Improvements Did Environmental Engineers.

Disease rates as measures of efficiency

Disease rates as measures of efficiency

“The final criterion of the efficiency of a purification plant is the absence or prevalence in the community of water-borne diseases. Typhoid fever being the most typical and widespread of such diseases, statistics of its prevalence are of much significance. Prior to the general introduction of purification works, the typhoid death rate was invariably high in many of our large cities drawing their suppy from polluted rivers and lakes. Most of these cities are now supplied with satisfactory water, and many records could be given showing the marked effect of water treatment on the typhoid rate. The following data for the cities of New Orleans, Pittsburgh and Cincinnati will suffice.”

Public Water-Supplies by Turneaure, Russell, Mead, Baker. John Wiley & Sons (1924) pages 430-431.

Page 20: Monroe L. Weber-Shirk S chool of Civil and Environmental Engineering Public Health Implications of Water Supply Improvements Did Environmental Engineers.

Evidence for a Causal Link:Pittsburgh, Philadelphia, Cincinnati

Evidence for a Causal Link:Pittsburgh, Philadelphia, Cincinnati

020406080

100120140160

1900 1910 1920 1930 1940

Year

Typ

hoid

mor

tali

ty r

ate

(per

100

,000

)

Typhoid

Filtration

Chlorination

01020304050607080

1900 1910 1920 1930 1940

Year

Typ

hoid

mor

tali

ty r

ate

(per

100

,000

)

Typhoid

Filtration

Chlorination

0

20

40

60

80

100

1900 1910 1920 1930 1940

Year

Typ

hoid

mor

tali

ty r

ate

(per

100

,000

)

Typhoid

Filtration

Chlorination

Pittsburgh, Cincinnati and New Orleans were used as evidence of the efficacy of filtrationPublic Water-Supplies by Turneaure, Russell, Mead, Baker. John Wiley & Sons (1924)

Page 21: Monroe L. Weber-Shirk S chool of Civil and Environmental Engineering Public Health Implications of Water Supply Improvements Did Environmental Engineers.

Delayed Response?Delayed Response?

0

10

20

30

40

50

1900 1910 1920 1930 1940

Year

Typ

hoid

mor

tali

ty r

ate

(per

100

,000

)

Typhoid

Filtration

Chlorination

0

5

10

15

20

25

30

35

1900 1910 1920 1930 1940

Year

Typ

hoid

mor

tali

ty r

ate

(per

100

,000

)

Typhoid

Filtration

Chlorination

0

5

10

15

20

25

1900 1910 1920 1930 1940

Year

Typ

hoid

mor

tali

ty r

ate

(per

100

,000

)

Typhoid

Filtration

Chlorination

“The steady reduction… is probably due in part to improved operation and in part to the gradual elimination of the disease from the community and so removing sources of contamination.”

Public Water-Supplies by Turneaure, Russell, Mead, Baker. John Wiley & Sons (1924)

Page 22: Monroe L. Weber-Shirk S chool of Civil and Environmental Engineering Public Health Implications of Water Supply Improvements Did Environmental Engineers.

Delayed Response?Delayed Response?

Gradual improvement in filtration plant operation

Gradual extension of water supply coverage

Gradual reduction in pathogen load in the population

01020304050607080

1900 1910 1920 1930 1940

Year

Typ

hoid

mor

tali

ty r

ate

(per

100

,000

)

Typhoid

Filtration

Chlorination

0

10

20

30

40

50

1900 1910 1920 1930 1940

Year

Typ

hoid

mor

tali

ty r

ate

(per

100

,000

)

Typhoid

Filtration

Chlorination

0

20

40

60

80

100

120

1900 1910 1920 1930 1940

Year

Typ

hoid

mor

tali

ty r

ate

(per

100

,000

)

Typhoid

Filtration

Chlorination

Page 23: Monroe L. Weber-Shirk S chool of Civil and Environmental Engineering Public Health Implications of Water Supply Improvements Did Environmental Engineers.

No Link?No Link?

New York

0

5

10

15

20

25

30

35

1880 1900 1920 1940year

Typ

hoid

mor

talit

y(p

er 1

00,0

00)

0

20MortalityNew sourceChlorinationFiltration

New York

Los Angeles

0

10

20

30

40

50

1880 1900 1920 1940year

Typ

hoid

mor

talit

y(p

er 1

00,0

00)

0

20MortalityNew sourceChlorinationFiltration

Los Angeles Minneapolis

0

20

40

60

80

1880 1900 1920 1940

year

Typ

hoid

mor

talit

y(p

er 1

00,0

00)

0

20MortalityNew sourceChlorinationFiltration

Minneapolis

Boston

0

20

40

60

80

1880 1900 1920 1940

year

Typ

hoid

mor

talit

y(p

er 1

00,0

00)

0

20MortalityNew sourceChlorinationFiltration

Boston

Page 24: Monroe L. Weber-Shirk S chool of Civil and Environmental Engineering Public Health Implications of Water Supply Improvements Did Environmental Engineers.

No Link?No Link?

San Francisco

0

20

40

60

80

1880 1900 1920 1940

year

Typ

hoid

mor

talit

y(p

er 1

00,0

00)

0

20MortalityNew sourceChlorinationFiltration

San Francisco

0

10

20

30

40

50

60

70

1900 1910 1920 1930 1940

Year

Typ

hoid

mor

tali

ty r

ate

(per

100

,000

)

Typhoid

Filtration

Chlorination

0

10

20

30

40

50

1900 1910 1920 1930 1940

Year

Typ

hoid

mor

tali

ty r

ate

(per

100

,000

)

Typhoid

Filtration

Chlorination

0

10

20

30

40

50

60

1900 1910 1920 1930 1940

Year

Typ

hoid

mor

tali

ty r

ate

(per

100

,000

)

Typhoid

Filtration

Chlorination

0

10

20

30

40

50

60

1900 1910 1920 1930 1940

Year

Typ

hoid

mor

tali

ty r

ate

(per

100

,000

)

Typhoid

Filtration

Chlorination

Page 25: Monroe L. Weber-Shirk S chool of Civil and Environmental Engineering Public Health Implications of Water Supply Improvements Did Environmental Engineers.

What else was happening?…education (one possibility)

What else was happening?…education (one possibility)

‘Infant care’ (US Children’s Bureau)12,000,000 copies

Baby care columns in leading newspapersCarried by nearly all newspapers by 1912

(though not a few years earlier)

‘Baby weeks’ By 1919: 17,000 local committees11,000,000 directly involved

Page 26: Monroe L. Weber-Shirk S chool of Civil and Environmental Engineering Public Health Implications of Water Supply Improvements Did Environmental Engineers.

Causes of diarrhoea according to ‘Diseases of children’

Causes of diarrhoea according to ‘Diseases of children’

1889 1899

Sour milk

Unripe fruit

Inhalation of sewer gas

Emanations from the soil

‘no doubt that the immediate cause is an infection of the alimentary canal, by …bacteria contained in milk or other forms of food’

EmpowermentPowerlessness!

Page 27: Monroe L. Weber-Shirk S chool of Civil and Environmental Engineering Public Health Implications of Water Supply Improvements Did Environmental Engineers.

Changes recommended: public health campaignChanges recommended: public health campaign

Breast feedBoil cow’s milk, sterilize bottlesProtect infants from persons known to be illControl fliesWash hands

You can improve your health!

Page 28: Monroe L. Weber-Shirk S chool of Civil and Environmental Engineering Public Health Implications of Water Supply Improvements Did Environmental Engineers.

Education of the PublicEducation of the Public

...the discovery of the possibilities of widespread social organization as a means of controlling disease was one which may almost be placed alongside the discovery of the germ theory of disease itself as a factor in the evolution of the modern public health campaign.

-Winslow (1929)

Page 29: Monroe L. Weber-Shirk S chool of Civil and Environmental Engineering Public Health Implications of Water Supply Improvements Did Environmental Engineers.

Confounding Factors:Order of InterventionsConfounding Factors:Order of Interventions

If the drinking water was contaminated with typhoid and you mounted an education campaign to encourage hand washing…You would conclude

If you installed a water treatment plant, but no one washed their hands…You would conclude

These interventions are necessary, but not sufficient because there are ________ disease transmission routes

No need to wash hands

No need for clean water

multiple

Page 30: Monroe L. Weber-Shirk S chool of Civil and Environmental Engineering Public Health Implications of Water Supply Improvements Did Environmental Engineers.

Typhoid in ReviewTyphoid in Review

Is it possible that education that led to improved hygiene was a significant source of the reduction in typhoid mortality?

This would suggest that water wasn’t the primary exposure route (unless individuals were taking steps to purify the water they drank)

We may never be able to untangle what happened with typhoid because multiple changes were occurring simultaneously

I’ll let you wrestle with who to give credit

Page 31: Monroe L. Weber-Shirk S chool of Civil and Environmental Engineering Public Health Implications of Water Supply Improvements Did Environmental Engineers.

Try again… Specific Disease Outbreaks (Attempt #2)

Try again… Specific Disease Outbreaks (Attempt #2)

Salmonella typhi was a bad eggInvestigate outbreaks and reported causes

TyphoidCholeraOther?

Check for evidence that it was waterborneCheck for evidence of protection by

filtration and/or chlorination

Page 32: Monroe L. Weber-Shirk S chool of Civil and Environmental Engineering Public Health Implications of Water Supply Improvements Did Environmental Engineers.

Sniffing out CholeraSniffing out Cholera

Courtesy of the National Library of Medicine

Page 33: Monroe L. Weber-Shirk S chool of Civil and Environmental Engineering Public Health Implications of Water Supply Improvements Did Environmental Engineers.

Cholera "Tramples the victors & the vanquished both."

Cholera "Tramples the victors & the vanquished both."

Seymour, Robert, 1798-1836. Artist.

Page 34: Monroe L. Weber-Shirk S chool of Civil and Environmental Engineering Public Health Implications of Water Supply Improvements Did Environmental Engineers.

John Snow: The great experimentJohn Snow: The great experiment

Snow's definitive work concerned the spread of cholera through water supplied by the Southwark Company and the Lambeth Company

Southwark obtained its water from the Thames at Batttersea, in the middle of London in an area almost certainly polluted with sewage

Lambeth Company obtained its water considerably upstream on the Thames, above the major sources of pollution

In an area containing about 300,000 residents the pipes of both companies were laid in the streets, and houses were connected to one or the other sources of supply.

Page 35: Monroe L. Weber-Shirk S chool of Civil and Environmental Engineering Public Health Implications of Water Supply Improvements Did Environmental Engineers.

Beautiful buildings, but the water…Beautiful buildings, but the water…

The view of three water companies by Hampton is southwest from the north side of the River Thames.  The nearest building of the three companies is the Southwark and Vauxhall Water Company

Source: Anonymous. Illustrated London News, 1855. Graciously provided by Bryce Caller, January 10, 2001.

Page 36: Monroe L. Weber-Shirk S chool of Civil and Environmental Engineering Public Health Implications of Water Supply Improvements Did Environmental Engineers.

Southwark and Vauxhall Water Company

Southwark and Vauxhall Water Company

In 1850, the microbiologist Arthur Hassall wrote of the River Thames water they were using,"...a portion of the inhabitants of the metropolis are made to consume, in some form or another, a portion of their own excrement, and moreover, to pay for the privilege." 

Next Cartoon presents John Edwards, owner of the Southwark Water Company, posing as Neptune ("Sovereign of the Scented Streams").  He is seen crowned with a chamber-pot, seated on a stool on top of a cesspool which doubles as the water-intake for the Southwark Water Company customers in south London. 

Page 37: Monroe L. Weber-Shirk S chool of Civil and Environmental Engineering Public Health Implications of Water Supply Improvements Did Environmental Engineers.

Southwark and Vauxhall Water Company

Southwark and Vauxhall Water Company

Courtesy of the National Library of Medicine

Page 38: Monroe L. Weber-Shirk S chool of Civil and Environmental Engineering Public Health Implications of Water Supply Improvements Did Environmental Engineers.

The Grand Cholera ExperimentThe Grand Cholera Experiment

Those houses served by the Lambeth Company had a low incidence of cholera, lower than the average population of London as a whole

Those served by the Southwark Company had a very high incidence

The socioeconomic conditions, climate, soil, and all other factors were identical for the populations served by the two companies

Snow concluded that the water supply was transmitting the cholera agent

Snow's study is impressive since the germ theory of disease had not yet been established

Proof that cholera was waterborne

Page 39: Monroe L. Weber-Shirk S chool of Civil and Environmental Engineering Public Health Implications of Water Supply Improvements Did Environmental Engineers.

Drinking Water Treatment and Germ Theory

Drinking Water Treatment and Germ Theory

1829: First sand filter used to treat some of London's drinking water

1850: John Snow established the link between drinking water (from a contaminated well) and Cholera

1872: Poughkeepsie, NY installs first filter in US 1885: Sand filters are shown to remove bacteria 1892: Cholera outbreak in Hamburg, Germany

Page 40: Monroe L. Weber-Shirk S chool of Civil and Environmental Engineering Public Health Implications of Water Supply Improvements Did Environmental Engineers.

1892 Cholera outbreak in Hamburg Germany

1892 Cholera outbreak in Hamburg Germany

Large outbreak of Cholera in Hamburg 17,000 cases; 8,600 deaths Very few cases in neighborhoods served by Altona's

filtered water supply Hamburg's sewers were upstream from Altona's intake!

Altona's water intake and filter beds Hamburg's sewer outfalls

HamburgAltona

Elbe RiverHamburg's water intake

Page 41: Monroe L. Weber-Shirk S chool of Civil and Environmental Engineering Public Health Implications of Water Supply Improvements Did Environmental Engineers.

Altona vs. Hamburg: Cholera CasesAltona vs. Hamburg: Cholera Cases

Hamburg

Altona

Cases in Altona acquired in Hamburg

Cholera cases

Received water from Altona

Cholera was waterborne

Slow sand filtration may have protected Altona

Page 42: Monroe L. Weber-Shirk S chool of Civil and Environmental Engineering Public Health Implications of Water Supply Improvements Did Environmental Engineers.

Environmental Engineers are saving the world: Attempt #3

Environmental Engineers are saving the world: Attempt #3

So it isn’t clear whether or not environmental engineers saved us all from typhoid. (you will be the judge!)

We have some evidence that filtration and water source affect public health

Could we make a case for our relevance by comparing current populations?

Compare modern countries with low and high U5MR and see what is correlated with infant mortality

Page 43: Monroe L. Weber-Shirk S chool of Civil and Environmental Engineering Public Health Implications of Water Supply Improvements Did Environmental Engineers.

U5MR by National Income in the Early 1990s

U5MR by National Income in the Early 1990s

0

0.05

0.1

0.15

0.2

0.25

0.3

0 2000 4000 6000 8000 10000

GNP per person$1991, purchasing power parity

U5M

R

Low performers (l to r): Congo, Gabon, Botswana, Turkey, Brazil

High performers (l to r): Sri Lanka, China, Surinam, Jamaica, Costa Rica

Page 44: Monroe L. Weber-Shirk S chool of Civil and Environmental Engineering Public Health Implications of Water Supply Improvements Did Environmental Engineers.

Good and poor performersGood and poor performers

High Low

* as % of GNP

<5 mortality rate

GNP/person

%underweight (<5yrs)

% with safe water

immunization %

spend on health*

pop'n per doctor

soldiers per doctor

the

contrast

nutrition

public

health

political

support

High: Sri Lanka, China, Surinam, Jamaica, Costa Rica

Low : Congo, Gabon, Botswana, Turkey, Brazil

26104

34884214

191887658576

3.62.7

24403638

813

Page 45: Monroe L. Weber-Shirk S chool of Civil and Environmental Engineering Public Health Implications of Water Supply Improvements Did Environmental Engineers.

Good and poor performersGood and poor performers

total fertility rate

yrs school f's >25**

maternal mortality

radios per 100

newspapers per 100

status of

women

communications

2.74.6

52

116446

3418

63

** mean yrs of schooling for women over 25

High LowHigh: Sri Lanka, China, Surinam, Jamaica, Costa Rica

Low : Congo, Gabon, Botswana, Turkey, Brazil

<5 mortality rate

GNP/person

the

contrast

26104

34884214

Page 46: Monroe L. Weber-Shirk S chool of Civil and Environmental Engineering Public Health Implications of Water Supply Improvements Did Environmental Engineers.

Conclusions: Good and Poor PerformersConclusions: Good and Poor Performers

Safe water supply is correlated with decreasing U5MR

Lower fertility rate, higher female education, lower maternal mortality rate are all correlated with lower U5MR

Increased communication correlated with lower U5MR!

Can’t prove cause and effect using this type of study

Page 47: Monroe L. Weber-Shirk S chool of Civil and Environmental Engineering Public Health Implications of Water Supply Improvements Did Environmental Engineers.

How might education increase child survival?

How might education increase child survival?

The whole country runs better as the education level increasesEducation as an indicator of how well the country

responds to the needs of its citizensEducation helps the group

Individuals make changes in personal habits that improve their own health and the health of those they interact withEducation helps the individual

Page 48: Monroe L. Weber-Shirk S chool of Civil and Environmental Engineering Public Health Implications of Water Supply Improvements Did Environmental Engineers.

The whole country runs better as the education level increases

The whole country runs better as the education level increases

Increased knowledge and changed outlook

Increased effectsof professional ‘interventions’

Better health

Changed public under-standing & behaviour

Increased income and better nutrition

Better use of publicand private resources

Institutional modernizatio

n

Page 49: Monroe L. Weber-Shirk S chool of Civil and Environmental Engineering Public Health Implications of Water Supply Improvements Did Environmental Engineers.

Would a Cornell Education help?Would a Cornell Education help?

If you moved to a poor neighborhood in Tegucigalpa, Honduras and raised a family would your children have a lower risk of dying than your neighbors?

Is there anything that you might do that would increase the survival odds for your children?

Does education help the individual?

Page 50: Monroe L. Weber-Shirk S chool of Civil and Environmental Engineering Public Health Implications of Water Supply Improvements Did Environmental Engineers.

Role of Hygiene and EducationRole of Hygiene and Education

Research in developing countries has shown that improvements in hygiene and sanitation have an even greater impact upon water-related diseases than improvements in water quality

Improvements in sanitation and personal hygiene reduce fecal-oral transmission 3 ways Objects (especially household items and including hands) Water Food

Water QUANTITY may be more important than water quality

Remember the Millennium Development Goal?_________________________Improved, not necessarily safe!

Page 51: Monroe L. Weber-Shirk S chool of Civil and Environmental Engineering Public Health Implications of Water Supply Improvements Did Environmental Engineers.

Fecal-Oral PathwaysFecal-Oral Pathways

Human excreta

Animal excreta

Dry sanitation involving reuse

Waterborne sewage

Non recycling latrines

Soil

Surface water

Ground water

Food

Drinking water

Oral

Pathogen source

Sanitation method

Land application

Environment Transport

Hands

Crops

Flies

Water

HygieneWater treatmentSanitation

washing

Page 52: Monroe L. Weber-Shirk S chool of Civil and Environmental Engineering Public Health Implications of Water Supply Improvements Did Environmental Engineers.

Intervention - Waterborne Sewage replace Land Application

Intervention - Waterborne Sewage replace Land Application

Human excreta

Animal excreta

Dry sanitation involving reuse

Waterborne sewage

Non recycling latrines

Soil

Surface water

Ground water

Food

Drinking water

Oral

Pathogen source

Sanitation method

Land application

Environment Transport

Hands

Crops

Flies

Water

IncreaseNo ChangeDecreaseUnknown

washing

Page 53: Monroe L. Weber-Shirk S chool of Civil and Environmental Engineering Public Health Implications of Water Supply Improvements Did Environmental Engineers.

Intervention – Personal HygieneIntervention – Personal Hygiene

Human excreta

Animal excreta

Dry sanitation involving reuse

Waterborne sewage

Non recycling latrines

Soil

Surface water

Ground water

Food

Drinking water

Oral

Pathogen source

Sanitation method

Land application

Environment Transport

Hands

Crops

Flies

Water

washing

IncreaseNo ChangeDecreaseUnknown

Page 54: Monroe L. Weber-Shirk S chool of Civil and Environmental Engineering Public Health Implications of Water Supply Improvements Did Environmental Engineers.

Hypothetical InterventionHypothetical Intervention

What are the public health effects of providing pure drinking water in abundance to a community that practices land application of waste and poor personal hygiene?

Page 55: Monroe L. Weber-Shirk S chool of Civil and Environmental Engineering Public Health Implications of Water Supply Improvements Did Environmental Engineers.

Conclusions on Hygiene and Health and Water (1)

Conclusions on Hygiene and Health and Water (1)

In order to achieve the primary objective of improving the health status of the community there is a need to improve attitudes, both with respect to hygiene in home and general health education, and implement these in conjunction with community water supply and environmental sanitation programs.

Most waterborne diseases spread through exposure of food and drinking water to human feces.

Hence, the rate of infection may be reduced by improving practice for disposal of human waste, as well as improving hygiene in the home and water quality and food hygiene.

Home hygiene and environmental sanitation: a country situation analysis for IndiaK.J. NATH

Page 56: Monroe L. Weber-Shirk S chool of Civil and Environmental Engineering Public Health Implications of Water Supply Improvements Did Environmental Engineers.

Conclusions on Hygiene and Health and Water (2)

Conclusions on Hygiene and Health and Water (2)

A supply of safe water would be of little benefit if it became contaminated because of unhygienic practices in the home.

Correct storage and handling of food and drinking water should be an important component of any program for promoting domestic hygiene.

On the other hand, improvement in the hygiene behavior of a community cannot be sustained without a concurrent improvement in the quality of environmental sanitation and the supply of safe drinking water.

Home hygiene and environmental sanitation: a country situation analysis for IndiaK.J. NATH

Page 57: Monroe L. Weber-Shirk S chool of Civil and Environmental Engineering Public Health Implications of Water Supply Improvements Did Environmental Engineers.

What would it take to reduce Diarrhea (and U5MR)?

What would it take to reduce Diarrhea (and U5MR)?

88% of diarrhoeal disease is attributed to unsafe water supply, inadequate sanitation and hygiene.

Improved water supply reduces diarrhea morbidity by 21%.

Improved sanitation reduces diarrhea morbidity by 37.5%. The simple act of washing hands at critical times can

reduce the number of diarrhoeal cases by up to 35%. Additional improvement of drinking-water quality, such as

point of use disinfection, would lead to a reduction of diarrhea episodes of 45%.

1.8 million people die every year from diarrhoeal diseases (including cholera); 90% are children under 5, mostly in developing countries.

1.6 9/11 attacks per day…

Page 58: Monroe L. Weber-Shirk S chool of Civil and Environmental Engineering Public Health Implications of Water Supply Improvements Did Environmental Engineers.

In search of more evidenceIn search of more evidence

Challenge: Assemble additional evidence for (or against) the role of filtration and chlorination

Remember, our goal is to propose interventions that make a positive improvement in public health

One goal of this course is to assemble evidence for the basis of sound decisions

A 2nd goal is to provide a solid theoretical basis for the interventions

Page 59: Monroe L. Weber-Shirk S chool of Civil and Environmental Engineering Public Health Implications of Water Supply Improvements Did Environmental Engineers.

The case against looking for a Public Health Outcome

The case against looking for a Public Health Outcome

Epidemiological studies to measure a decrease in diarrhea in young children are Expensive Take a good deal of time Are not guaranteed to produce any meaningful results even from

the most successful program Diarrhea is caused by many different pathogens through

many different transmission routes Confounding factors Need to have an adequate control group Results have little diagnostic power

Page 60: Monroe L. Weber-Shirk S chool of Civil and Environmental Engineering Public Health Implications of Water Supply Improvements Did Environmental Engineers.

An Alternative to EpidemiologyAn Alternative to Epidemiology

WHO’s Minimum Evaluate Procedure

constructionfunctioning

O&Muse benefits

Page 61: Monroe L. Weber-Shirk S chool of Civil and Environmental Engineering Public Health Implications of Water Supply Improvements Did Environmental Engineers.

Review: Public Health Implications of Water Supply Improvements

Review: Public Health Implications of Water Supply Improvements

The life expectancy transition The role of water supply, sanitation, and hygiene

In the Global North a century ago In the Global South

The U5MR connection Exposure Routes: breaking the cycle Pathogens in the loop Implications for successful interventions

0

20

40

60

80

100

1650 1700 1750 1800 1850 1900 1950 2000 2050

Year

life

ex

pec

tan

cy (

yea

rs)

Pre-agrarian

Poor-agrarian Early C

ities

Modern Cities

The transition

0

5

10

15

20

25

30

35

1900 1910 1920 1930 1940 1950

year

deat

hs p

er 1

00,0

00

0

0.05

0.1

0.15

0.2

0.25

0.3

0 2000 4000 6000 8000 10000

GNP per person$1991, purchasing power parity

U5M

R

Human excreta

Animal excreta

Dry sanitation involving reuse

Waterborne sewage

Non recycling latrines

Soil

Surface water

Ground water

Food

Drinking water

Oral

Land application

Hands

Crops

Flies

Water

washing

Mean = life expectancy

0

5000

10000

15000

20000

25000

0 2 8 13 18 23 28 33 38 43 48 53 58 63 67 72 77 82 89

Mean age at death in interval (nearest year)

Num

ber

of d

eath

s / y

r (f

or 1

0000

0 bi

rths

/yr) Mean = life expectancyMean = life expectancy

0

5000

10000

15000

20000

25000

0 2 8 13 18 23 28 33 38 43 48 53 58 63 67 72 77 82 89

Mean age at death in interval (nearest year)

Num

ber

of d

eath

s / y

r (f

or 1

0000

0 bi

rths

/yr)

Page 62: Monroe L. Weber-Shirk S chool of Civil and Environmental Engineering Public Health Implications of Water Supply Improvements Did Environmental Engineers.

A sample of Waterborne Pathogens

Enteropathogenic Escherichia coli (EPEC) Vibrio cholerae - CholeraSalmonella typhi - Typhoid Cryptosporidium parvum Hepatitis A

Page 63: Monroe L. Weber-Shirk S chool of Civil and Environmental Engineering Public Health Implications of Water Supply Improvements Did Environmental Engineers.

Enteropathogenic Escherichia coli (EPEC)

Enteropathogenic Escherichia coli (EPEC)

Enteropathogenic Escherichia coli (EPEC) strains are one of several categories of pathogenic E. coli strains that cause diarrhea. EPEC infections are prevalent on six continents

In many parts of the world, EPEC strains are the most common bacterial cause of diarrhea in infants

Disease due to EPEC can be severe, refractory to oral rehydration, protracted, and lethal

Page 64: Monroe L. Weber-Shirk S chool of Civil and Environmental Engineering Public Health Implications of Water Supply Improvements Did Environmental Engineers.

Cryptosporidium parvumCryptosporidium parvum

Cryptosporidium parvum, a single-celled animal, i.e., a protozoa, is an obligate intracellular parasite.

Cryptosporidium sp. infects many herd animals (cows, goats, sheep among domesticated animals, and deer and elk among wild animals). It is currently thought that the form infecting humans is the same species that causes disease in young calves.

The infective stage of the organism, the oocyst is 3 mm in diameter.

The sporocysts are resistant to most chemical disinfectants, but are susceptible to drying and the ultraviolet portion of sunlight.

How widespread is Cryptosporidium?This might affect our interventions.

Page 65: Monroe L. Weber-Shirk S chool of Civil and Environmental Engineering Public Health Implications of Water Supply Improvements Did Environmental Engineers.

Hepatitis A VirusHepatitis A Virus

Hepatitis A is usually a mild illness characterized by sudden onset of fever, malaise, nausea, anorexia, and abdominal discomfort, followed in several days by jaundice. The infectious dose is unknown but presumably is 10-100 virus particles.

HAV is excreted in feces of infected people and can produce clinical disease when susceptible individuals consume contaminated water or foods.

In developing countries, the incidence of disease in adults is relatively low because of exposure to the virus in childhood. (Immunity!)

In the U.S., the percentage of adults with immunity increases with age (10% for those 18-19 years of age to 65% for those over 50).

Page 66: Monroe L. Weber-Shirk S chool of Civil and Environmental Engineering Public Health Implications of Water Supply Improvements Did Environmental Engineers.

Implications for Successful Interventions

Implications for Successful Interventions

Break the major pathogen loops……for the major pathogensHygiene is importantSanitation (waste disposal) is importantWe need more information on the efficacy

of the various water purification technologies so we can break the waterborne route

Page 67: Monroe L. Weber-Shirk S chool of Civil and Environmental Engineering Public Health Implications of Water Supply Improvements Did Environmental Engineers.

Web discussion boardWeb discussion board

Use it to post questions to me that may be of general interest

I receive an email whenever an item is posted, so I can respond quickly

Use the discussion board to post discoveries and questions related to the course topic