Waterborne Diseases: Public Health Engineering and the Primacy of Prevention David M.

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Transcript Waterborne Diseases: Public Health Engineering and the Primacy of Prevention David M.

Waterborne Diseases: Public Health
Engineering and the Primacy of Prevention
David M. Gute, Ph.D., M.P.H., FACE
Tufts Environmental Literacy Institute
May 21, 2013
Today’s Talk
• My background in government and the
practice of public health
• Tufts Environmental Literacy Institute
• Primary prevention: Public health engineering
• Nexus: water, health, and food
• Importance of surveillance and acquisition of
data
• Environmental enteropathy
• Renewed emphasis on sanitation
Epidemiological Triad
Host
Vector
Agent
Environment
Fenwick, A. Science 8/25/06
Condition
Cases in Africa
Hookworm
198 million
% of Global
Burden (Africa)
27-34%
Ascariasis
173 million
14-22%
Schistosomiasis
166 million
89%
Trichuriasis
162 million
20-26%
Lymphatic
Filariasis
46 million
38%
Trachoma
33 million
40%
Onchocerciasis
18 million
99%
Public Health
Approach
Surveillance:
What
is the
problem?
Problem
Implementation:
How do you
do it?
Intervention
Evaluation:
What
works?
Risk Factor
Identification:
What is the
cause?
Response
The Primacy of Prevention
• The public health approach
• Success stories
– Impact of civil infrastructure improvements and
other factors versus medical treatment
– Removal of lead in gasoline
Levels of Prevention
• Primary- prevention of the disease in a person
who is well and does not have the disease in
question.
• Secondary- the identification of the disease at
an early stage in the natural history of the
disease in question.
• Tertiary- the limitation of mortality and or
disability of the disease in question.
The Questionable Impact of Medical
Measures (McKinlay et al.)
An Unqualified Success: Blood Lead
Measurements
1975-1981
(USA)
110
18
Predicted blood lead
100
Lead used
in
90
gasoline
(thousands
of tons) 80
16
Mean
blood
lead
14 levels
 g/dl
Gasoline lead
70
Observed blood lead
12
60
50
10
40
30
1975
1976
1977
1978
Year
1979
1980
1981
8
Source: Pirkle et al JAMA 272:284-91, 1994
EPA’s Perspective on Levels of Prevention
Source:
http://www.epa.gov/p2/p2week2003.htm
Water
• “Water is a global dictator which sets the
limits for living nature.”
Simo Laakkonen
Water and Urbanization: Conceptualizing
Hydrohistory” unpublished paper. As cited in
The Sanitary City by Martin Melosi.
He also said, “Waste disposal-an unwelcome but
necessary function-is another global dictator”.
Global Warming
Pollution
Habitat Degradation
Over Population
Health
Over Consumption
Biodiversity Loss
Mark Pokras, D.V.M.
EID = Emerging
Infectious Disease
Mark Pokras, D.V.M.
Surveillance
• The systematic and ongoing collection, analysis and
dissemination of information on disease, injury, or
hazard for the prevention of morbidity and mortality.
• Sources of data appropriate for surveillance?
• Case-based: Sentinel Health Event of Occupational
Origin (SHE/O)
• Rate-based: population based analysis looking down
the traditional public health/epidemiological
parameters of person, place, and time.
• Surveillance can be directed either at the disease or
the agent (more commonly known as monitoring).
Emerging Infectious Diseases, Volume 9, Number 5, May 2003
Estimating the Incidence of Typhoid Fever and Other Febrile Illnesses in Developing Countries
John A. Crump,* Fouad G. Youssef,† Stephen P. Luby,* Momtaz O. Wasfy,† Josefa M. Rangel,* Maha Taalat,† Said A. Oun,‡ and Frank J. Mahoney*†
*Centers for Disease Control and Prevention, Atlanta, Georgia, USA; †U.S. Naval Medical Research Unit No. 3, Cairo, Egypt; and ‡Ministry of Health and Population, Cairo,
Egypt
How well do we understand the
burden of waterborne diseases?
….issues of surveillance
• Sewage into Lake
Michigan / Chicago River:
drinking water source
North Chicago River
• 1867: 2-mile tunnel
provides drinking water
intake away from shore
• 1869: water tower fire
pumping station
• 1871: deepening of
Illinois and Michigan
canal, reversing current
of Chicago River –
sewage flows away from
water intakes
1871
Original
South Chicago River
• 1893: 4-mile intake;
nd closure of all
rdshoreline sewage outlets
• 1917: City-wide chlorination of public water supply
• Dramatic effects before chlorination due to sanitation
2 and 3 stages
Adapted from Ferrie and Troesken, Explor. In Ec. Hist. 2007
First intake in Lake Michigan
Reversal Chicago River
No sewage allowed in LM
Intakes further out
2nd and 3rd stages
Chlorination
Adapted from Ferrie and Troesken, Explor. In Ec. Hist. 2007
A Case Study: Schistosomiasis
• 200 million cases world-wide with another 600
million at risk of infection.
• A parasitic disease with a complex life cycle.
• In the perspective of Nobel Laureate Joshua
Lederberg, a well “adapted” microbe.
• Predominate risk management tactic today is
treatment. This is a missed opportunity to further
primary as contrasted with tertiary prevention.
Neglected Tropical Diseases
• Neglected Tropical Diseases (NTDs), such as
urogenital schistosomiasis (UGS), receive little global
attention as measured by research and development
investment. As a result, NTDs burden health care
systems and are an important cause of squandered
human potential.
• UGS causes anemia; fibrosis of the liver, bladder and
ureter; renal damage; bladder cancer; urogenital
pathology; and infertility.
Mass Chemotherapy
• Mass chemotherapy is the prevailing response to
Schistosomiasis.
• However, mass chemotherapy campaigns have been unable to
reduce prevalence below 5-15% (Wang et al. 2009) because
they do not address the root cause of the disease which is
repeated exposure to parasites.
• Emphasis on the beneficial impact of infrastructure to other
water-related diseases was endorsed emphatically by the C.H.
King editorial that accompanied the publication of Wang’s
successful control efforts in China (King, 2009).
Impacts of our proposed
clinical trial on the multi-host
lifecycle of S. haematobium
X1 shows the interruption of
S. haematobium infection
due to use of water
recreation areas and
borehole wells; X2 shows the
interruption of morbidity
and egg production in
humans due to treatment
with praziquantel; X3 shows
the reduction of river water
contamination with S.
haematobium eggs because
of latrine use; and X4
illustrates the interruption
of multiple stages of the
lifecycle due to behavior
change resulting from
Adapted fromeducation and access to
http://www.dpd.cdc.gov/dpdx/HTML/Ima
WASH
geLibrary/SZ/Schistosomiasis/body_Schistosomiasi
s_il10.htm
The Water Source on the Awusu River
Urine Samples from Schoolchildren
Adasawase, Ghana
Karen C. Kosinski,
MSPH, Ph.D.
Water Recreation Area Adasawase,
Ghana
Karen Kosinski, Ph.D.
The WRA in Use
The WRA features a concrete
pool supplied by a bore hole
well and a gravity –driven
rainwater collection system in
this water-rich location.
Initial baseline testing in 2008
established that 42.5% of
children were egg positive. In
2009 with drug treatment
alone the pre-WRA annual
cumulative incidence of
infection was 13.4%. In 2010,
this incidence rate fell
significantly (p <0.001, chisquared) to 3.7% after
installation of the WRA.
KC Kosinski, MN Adjei, KM Bosompem, JJ Crocker, JL Durant, D
Osabutey, JD Plummer, MJ Stadecker, AD Wagner, M Woodin,
and DM Gute. Effective Control of Schistosoma haematobium
Infection in a Ghanaian Community following Installation of a
Water Recreation Area.
PLoS Negl Trop Dis . Jul 2012 6(7): p. e1709.
Dietary
insufficiency
which worsens
Malnutrition
Infection
which worsens
Environmental
factor: water
Jeffrey Griffiths, M.D.
Nice normal intestine. Note
long skinny finger-like villi,
which absorb nutrients
ENVIRONMENTAL
ENTEROPATHY
EE -Nasty blunted villi, and
tissue is infiltrated with
inflammatory cells. EE is a state
of chronic inflammation
Korpe & Petri, Trends in Molecular Medicine June 2012, Vol. 18, No. 6
Environmental Enteropathy
Children in highly contaminated environments have
leaky, chronically inflamed intestines – 5% less
carbohydrate, 15% less protein absorption. Leak lets
‘dirty’ contents of gut into body; chronic inflammation
uses up/diverts nutrients, leads to anemia…
Gnotobiotic (sterile gut) mice – given either
Normal or Kwashiorkor MB. Science:339.548-554, 2013
Mice given normal MB
– maintained weight
Mice given kwashiorkor
MB bacteria – lost 1/3 of
their weight
Solutions for Environmental Enteropathy
• Classic household water & sanitation – water
supply NOT same for animals unless treated;
hand-washing; human and animal feces kept
out of wastewater to increase food safety.
• Agricultural hygiene – barriers to keep feces
out of water - vegetated buffer zones- riparian
buffers to slow entry into open water (stream
or irrigation canal), nutrient management,
grazing practices …
January 4 2013: US FDA proposes rules to “ensure water used in irrigation meets standards…”
http://www.fda.gov/Food/FoodSafety/FSMA/ucm334114.htm
Integrated Approach
• Providing food to undernourished people only solves
some of the problem. Recent science: contaminated
environments, infections, and toxins adversely change
the child’s gut via EE.
• Water & sanitation have much more potential to
eliminate malnutrition than had been thought.
• Integrated programming has the best chance to
improve the nexus of water, health, and food. One can’t
dig irrigation canals without affecting nutrition & health!
• Schistosomiasis = disease of “progress”.
Definition of Engineering
Engineering is the invention of solutions for the
improvement of the human condition - often in
the face of incomplete understanding and
always under the constraints of natural laws
and available resources.
Source: Dean Paul Fleury. Engineering Program @ Yale University
Selected Data Points Regarding the
Schism
• 1922, MIT & Harvard abandoned a joint
program: the School for Health Officers.
Harvard School of Public Health emerges-like
the Phoenix.
• 1970, US EPA created out of the US Public
Health Service.
• 1970, (MA) Department of Environmental
Quality Engineering (DEQE) created.
Engineering Village 2 Citations for “Public Health Engineering” Expressed as
a Title by Date of Publication (English Only)
Date of Publication
Counts
Present -1990
9
1989-1970
5
1969-1950
14
1949-1930
28
1929-1910
13
1909-1890
2
Source: D.M. Gute
OVID Citations for “Public Health Engineering” Expressed as a Title by Date
of Publication (Any Language)
Date of Publication
Counts
Present -1990
2
1989-1970
4
1969-1950
11
1949-1930
N.A.
1929-1910
N.A.
1909-1890
N.A.
Source: D.M. Gute
Sir Joseph Bazalgette
•
•
Sir Joseph Bazalgette (1819-91).
Bazalgette was one of the greatest of
Victorian engineers who, between
1856 and 1889, built more of London
than anyone else before or since in
his role as Chief Engineer to the
Metropolitan Board of Works. The
sewers, pumping stations and
treatment works that he built are still
keeping the capital clean.
Before Bazalgette's time London's
sewage flowed into the Thames from
which it leaked into adjacent springs,
wells and other sources of drinking
water: hence the cholera epidemics.
Sir Edwin Chadwick
• Father of sanitary engineering in
England
• A lawyer by training
• Health depended on sanitation
• Sanitation was in the province of
engineering
• One local authority should
administer sanitary infrastructure
in an area
• Took on the entrenched power
structure of engineers and private
water companies
• For his trouble, he was fired.
Knighted barely one year before
his death.
Lemuel Shattuck
• New Englander influenced by the work of
Chadwick.
• In 1850 drafts a report laying out the rationale
for the creation of Board of Health for the
Commonwealth of Massachusetts. (See
handout).
• The plan is acted on 19 years later!
• Founder of the American Statistical
Association.
Shattuck and Satcher
•
•
Shattuck: “public health requires such laws and regulations, as will secure to man
associated in society, the same sanitary enjoyments that he would have as an
isolated individual ”.
Satcher: “scope has broadened to include: identifying elusive patterns and origins
of human behaviors that so frequently result in adverse health consequences”.
Deer Island
Source: MWRA Homepage
Biology of Water and Health
9/21/10
Vector Borne Disease Comes to NYC or
at least to the New Yorker
Conclusion
• Engineering and public health will benefit
from a re-convergence.
• The hope is that primary prevention can be
emphasized and that emerging technologies
can be harnessed to both enhance the
understanding of disease etiology and
mechanisms of control.
• Integrate environmental concepts and
material in outreach and communication
materials