Typhoid Fever - Library

Assessment of Water, Sanitation, and Hygiene
Interventions in Response to an Outbreak of
Typhoid Fever in Neno District, Malawi
Sarah D. Bennett, MD, MPH
Lieutenant, U.S. Public Health Service
April 13, 2011
Division of Foodborne, Waterborne, and Environmental Diseases
National Center for Emerging and Zoonotic Infectious Diseases
Division of Foodborne, Waterborne, and Environmental Diseases

Typhoid Fever
Salmonella enterica serovar Typhi
21 million illnesses and 200,000
deaths
Humans are the only known
reservoir
Infection through contact with
contaminated food or water

Outbreak Timeline
Onset
Neno District
Malawi
Tsangano District
Mozambique
May
2009
Aug Oct April June Aug Sept

Outbreak Timeline
Onset
Multinational investigation
May June Aug Oct Dec Feb April
2009
2010
June Aug Sept
302 cases

Outbreak Timeline
Onset
Multinational investigation
May June Aug Oct Dec Feb April
2009
2010
June Aug Sept
Prevention interventions

Outbreak Timeline
Multinational investigation
Onset
Rainy season
May June Aug Oct Dec Feb April
2009
2010
June Aug Sept
Prevention interventions

Interventions
Community meetings or “Typhoid Talks”
• Cause, treatment and prevention of typhoid fever
• Household stored water treatment
Distribution of WaterGuard
• Locally produced
• Dilute sodium hypochlorite solution
Infrastructural improvements
• Boreholes
• Pit latrines

Outbreak Timeline
Multinational investigation
Onset
Rainy season
784 cases
44 deaths
May June Aug Oct Dec Feb April
2009
2010
June Aug Sept
Prevention interventions

Outbreak Timeline
Multinational investigation
Onset
Rainy season
WASH Survey
May June Aug Oct Dec Feb April
2009
2010
June Aug Sept
Prevention interventions

Impact of prevention
interventions on
WASH Survey Objectives
• Knowledge of cause and
prevention of typhoid fever
• Knowledge, attitudes and
practices regarding safe water
• Receipt and use of WaterGuard

17 villages
Methods: WASH Survey
• Neno District, Malawi
• Reported cases in 2009 and 2010
10-12 female heads of
household per village
• Randomly selected

Methods: Household Stored Water Testing
Free residual chlorine testing

Response Rate
393 households visited
202 households enrolled

Response Rate
393 households visited
187 unavailable
4 refused
202 households enrolled

Demographics
All Respondents
(n=202)
Mean age (range) 35 (18-83)
Mean persons per household (range) 5 (1-12)
No education 25%
Self-reported literacy 57%

Attendance at a “Typhoid Talk”
56% reported attending a
“Typhoid Talk”
Talks led by
• Community Health Workers
• Clinicians
• NGO’s

Reported Causes of Typhoid Fever
Total
(n=202)
Poor hygiene 73%
Drinking bad water 47%
Eating bad food 27%

Reported Causes of Typhoid Fever
Typhoid Talk
(n=111)
No Typhoid Talk
(n=87)
p-value
Poor hygiene 85% 64% < 0.01
Drinking bad water 55% 42% 0.02
Eating bad food 34% 21% 0.13

Reported Methods of Prevention
Total
(n=202)
Treat water 65%
Wash hands 50%
Clean cooking utensils /
vessels
36%
Cook food thoroughly 34%

Reported Methods of Prevention
Typhoid Talk
(n=111)
No Typhoid Talk
(n=87)
p-value
Treat water 70% 63% 0.30
Hand washing 52% 51% 0.89
Clean cooking utensils /
vessels
44% 26% 0.04
Cook food thoroughly 32% 38% 0.55

Impact of “Typhoid Talks” on Knowledge of Cause
and Prevention of Typhoid Fever
Household understanding of causes and methods of
preventing typhoid fever are low
Attendance at a “Typhoid Talk”
• Improved knowledge of hygiene and water as causes
• Did not improve knowledge of food as a potential cause
• Did not significantly improve knowledge of prevention methods

Sources of Household Water
4% Rivers
48% Boreholes 46% Unprotected
wells
2% Public Taps

Additional Sources of Household Water
57% Unprotected wells
6% Rivers
Primary borehole users
3% Another borehole

Treatment of Household Stored Water
70% reported treating water in preceding 2 weeks
Most common reasons for not treating water
• Lack of WaterGuard (57%) or 1% stock chlorine solution (40%)
• Current water is safe (18%)
• Too busy (12%)
• Bad taste or smell associated with treatment (2%)

Methods of Treating Household Stored Water
100% 98%
2009
89%
2010
79%
80%
Reported Frequency
60%
40%
20%
47% 48%
23%
36%
16%
0%
Any chlorine product WaterGuard 1% stock chlorine solution Boiling

WaterGuard in the Home
84% received free WaterGuard
53% had WaterGuard observed in
the home
• 33% used to treat currently stored water

Free Residual Chlorine Testing
Adequate Free
Residual Chlorine*
All households with stored water
15% (n=152)
Households who reported treating
water with WaterGuard
63% (n=38)
*Adequate free residual chlorine defined as ≥ 0.2 milligrams per liter

Impact of Interventions on Knowledge, Attitudes and
Practices of Safe Water
Most households use unimproved sources of water
WaterGuard was distributed
• Few used it to treat stored water
• Supply insufficient to treat all stored water
Adequate chlorine levels in few households
Most households do not have safe drinking water

Limitations of WASH Survey
Lack of a baseline evaluation for comparison
Challenges in typhoid fever surveillance
Ongoing prevention activities during survey
High rate of unavailable target respondents

Conclusions
Knowledge of relationship between unsafe water,
food and typhoid fever remains low
“Typhoid Talks” improved knowledge of poor
hygiene and unsafe water as causes
• Did not improve knowledge of food as cause
• Did not improve knowledge of prevention methods
WaterGuard was distributed, but use is low
Many households remain without safe drinking water

Recommendations
Improve attendance and effectiveness of educational
campaigns or “Typhoid Talks”
• Increase knowledge of typhoid fever
• Emphasize importance of household stored water treatment
Improve delivery and promote use of WaterGuard
• Sustainable access to WaterGuard at household level
Continue improvement of water and sanitation
infrastructure in Neno District

Acknowledgements
WHO
Ministry of Health, Malawi
Neno District Health Office
UNICEF
Partners in Health
USAID
PSI
Action Aid
All the staff, enumerators and
drivers who participated in planning,
logistics and data collection
CDC
• Lauren Blum
• Cheryl Bopp
• Linda Capewell
• Austin Demby
• Holly Dentz
• Leonard Floyd
• Mike Humphreys
• Sara Lowther
• Eric Mintz
• Benjamin Nygren
• Michele Parsons
• Jim Sejvar
• Ethel Taylor
• Tom Warne

Thank you!
For more information please contact Centers for Disease Control and
Prevention
1600 Clifton Road NE, Atlanta, GA 30333
Telephone, 1-800-CDC-INFO (232-4636)/TTY: 1-888-232-6348
E-mail: cdcinfo@cdc.gov Web: www.cdc.gov
The findings and conclusions in this report are those of the authors and do not necessarily represent the official
position of the Centers for Disease Control and Prevention.
National Center for Emerging and Zoonotic Infectious Diseases
Division of Foodborne, Waterborne and Environmental Diseases

ADDITIONAL SLIDES

Outbreak Timeline
Multinational investigation
Onset
Rainy season
WASH Survey
784 cases
44 deaths
May June Aug Oct Dec Feb April
2009
2010
302 cases
June Aug Sept
Prevention interventions

Epidemic Curve for Typhoid Fever Outbreak
Number of Cases
100
90
80
70
60
50
40
30
20
10
0
Active Surveillance
(Outbreak investigation)
Mar Apr May June July Aug Sept Oct Nov Dec Jan Feb Mar Apr May June July Aug Sept
2009 2010
Passive Surveillance
Laboratory
Capacity
Building
Month and Year Suspected Probable Confirmed

Early Intervention
Late Intervention
Nsambe
Clinic
Neno District
Hospital

Attendance at a “Typhoid Talk” by Village
Village
Targeted
Education
"Typhoid Talk"
Attendance
Chakulembera Yes 64%
Chikalema No 36%
Chimbalanga I Yes 36%
Chimbalanga II Yes 33%
Chiyembekeza Yes 82%
Kagudza Yes 58%
Kaingilira Yes 58%
Kalimedzako Yes 33%
Kamoto No 33%
Kumbwani Yes 33%
Kundembo Yes 45%
Kweneza Yes 92%
Masamba Yes 67%
Moffat Yes 67%
Mposadala Yes 67%
Mtemankhawa Yes 83%
Nseula Yes 64%

Results: Products Received at “Typhoid Talk”
100%
80%
84%
78%
Reported Frequency
60%
40%
30%
20%
14%
11%
5%
0%
WaterGuard Soap Advice or
information
1% stock
chlorine
solution
Print materials
T-shirt

Reported Causes of Typhoid Fever
Total
(n=202)
Typhoid Talk
(n=111)
No Typhoid Talk
(n=87)
p-value
Poor hygiene 73% 85% 64% < 0.01
Drinking bad water 47% 55% 42% 0.02
Eating bad food 27% 34% 21% 0.13
Flies 7% 11% 3% 0.06
Unwashed fruits / vegetables 7% 6% 9% 0.24
Don't know 14% 5% 20% 0.01

Reported Methods of Prevention
Total
(n=202)
Typhoid Talk
(n=111)
No Typhoid Talk
(n=87)
p-value
Treat water 65% 70% 63% 0.30
Hand washing 50% 52% 51% 0.89
Clean cooking utensils /
vessels
36% 44% 26% 0.04
Cook food thoroughly 34% 32% 38% 0.55
Wash fruits / vegetables 18% 13% 25% 0.14
Don’t know 7% 1% 10% 0.01

96% would go to a
health facility
Treatment of Typhoid Fever
3% reported a home
remedy
Traditional healers were
not mentioned by any
respondent

Diseases Caused by Drinking Unsafe Water
Reported Frequency
100%
80%
60%
40%
20%
0%
89%
37%
44% attending a “Typhoid Talk” compared
to 31% not attending a talk (p = 0.04)
33%
21%
18%
11%
Diarrhea Typhoid Cholera Malaria Fever Dysentery Don't know
2%

Storage of Household Water
74% wide-mouthed vessels
• 57% covered
• 99% scoop with ladle / cup
27% narrow-mouthed vessels
• 99% pour water

Uses of Household Stored Water
100%
92%
80%
Reported Frequency
60%
40%
66%
57%
39%
30%
20%
0%
Cooking
Washing cooking
utensils / vessels
Bathing Washing fruits /
vegetables
Washing clothes

Markers of Water Safety
100%
80%
Reported Frequency
60%
40%
20%
0%
54%
Appearance
28%
It is
protected
35% reported clear water can make them sick
19%
16%
11%
Smell Taste Containers
are clean /
covered
2%
People get
sick
19%
Don't know

Reasons for Treating Household Stored Water
Overall
Typhoid Talk
(n=111)
No Typhoid Talk
(n=87)
p-value
Makes water safer 83.4% 81.0% 88.0% 0.10
CHW visited village to talk about it 19.4% 26.3% 11.9% 0.04
Received water treatment for free 7.3% 11.0% 3.4% 0.01
Someone at health facility said important 3.8% 3.3% 2.3% 0.54
Family / friends said important 1.2% 0.0% 2.6% Undefined

Receipt and Observed WaterGuard by Village
Village
WaterGuard
Distribution
Reported Receipt of
WaterGuard
Observed WaterGuard
in Home
Chakulembera Yes 100% 27%
Chikalema No 25% 0%
Chimbalanga I Yes 92% 50%
Chimbalanga II Yes 100% 92%
Chiyembekeza Yes 100% 50%
Kagudza Yes 100% 100%
Kaingilira Yes 100% 50%
Kalimedzako Yes 100% 92%
Kamoto No 0% 0%
Kumbwani Yes 100% 73%
Kundembo Yes 100% 83%
Kweneza Yes 100% 58%
Masamba Yes 100% 58%
Moffat Yes 100% 50%
Mposadala Yes 100% 58%
Mtemankhawa Yes 100% 33%
Nseula Yes 100% 80%

Receipt and Observed WaterGuard by Village
Village
WaterGuard
Distribution
Reported Receipt of
WaterGuard
Observed WaterGuard
in Home
Chakulembera Yes 100% 27%
Chikalema No 25% 0%
Chimbalanga I Yes 92% 50%
Chimbalanga II Yes 100% 92%
Chiyembekeza Yes 100% 50%
Kagudza Yes 100% 100%
Kaingilira Yes 100% 50%
Kalimedzako Yes 100% 92%
Kamoto No 0% 0%
Kumbwani Yes 100% 73%
Kundembo Yes 100% 83%
Kweneza Yes 100% 58%
Masamba Yes 100% 58%
Moffat Yes 100% 50%
Mposadala Yes 100% 58%
Mtemankhawa Yes 100% 33%
Nseula Yes 100% 80%

Geographic Receipt of WaterGuard
Total
(n=202)
Early
Intervention
(n=106)
Late
Intervention
(n=96)
p-value
Received free WaterGuard 84% 100% 74% undefined
Observed WaterGuard 53% 53% 54% 0.99

Number of Times Received Free WaterGuard
100%
80%
Reported Frequency
60%
40%
20%
11%
6%
12%
21% 23%
12%
15%
0%
Never Once 2 Times 3 Times 4 Times 5 Times > 5 Times

Methods of Treating Household Stored Water
Overall
Typhoid Talk
(n=111)
No Typhoid Talk
(n=87)
p-value
WaterGuard 89.3% 94.5% 83.7% < 0.01
1% Stock chlorine solution 23.0% 22.3% 24.1% 0.82
Boiling 16.0% 15.8% 17.4% 0.81

Free Residual Chlorine Testing
Adequate Free
Residual Chlorine*
All households with stored water 15%
Households who reported treating water 59%
Households who reported treating water with
WaterGuard
63%
*Adequate free residual chlorine defined as ≥ 0.2 milligrams per liter

Free Residual Chlorine Testing
Adequate Free Residual Chlorine
Overall
Typhoid
Talk
No Typhoid
Talk
p-value
All households with stored water 15% 20% 11% 0.11
Households who reported treating
water
59% 64% 49% 0.53
Households who reported treating
water with WaterGuard
63% 72% 49% 0.33

100%
92%
Hand Hygiene
When should you wash your hands
80%
74%
Reported Frequency
60%
40%
50%
38%
20%
13%
0%
After using toilet Before eating After cleaning
babies
Before cooking All 4
recommended

When to Wash Hands
Overall
(n=202)
Typhoid Talk
(n=11)
No Typhoid Talk
(n=87)
p-value
After using toilet 92% 94% 91% 0.42
Before eating 74% 83% 64% 0.01
After cleaning babies 50% 53% 48% 0.64
Before cooking 38% 41% 37% 0.56
All 4 guidelines 13% 12% 14% 0.71

Hand Washing Stations
WATER
SOAP
77% reported soap in
the home
46% use soap for hand
washing
Only 1 / 202 households
with a functional hand
washing station

Reported Latrine Use
100%
80%
Reported Frequency
60%
40%
51%
43%
20%
0%
9%
Own latrine Shared latrine Open defecation

Latrine Use by Intervention Village
Total
(n=202)
Early
Intervention
(n=106)
Late
Intervention
(n=96)
p-value
Own latrine 51% 71% 38% < 0.01
Shared latrine 43% 29% 51% 0.04
Open defecation 9% 2% 12% 0.01

Bacterial coliform and E.coli testing
PAIRED SAMPLES
5 out of 9 boreholes and all 3 public taps were
positive for bacterial coliforms and E. coli

Malawi-Mozambique Border
MALAWI
MOZAMBIQUE
KWENEZA VILLAGE
NSAMBE CLINIC
DACKSON CLINIC

Low refusal rate
Strengths of WASH Survey
Inclusion of all 17 villages affected by 2009-2010
outbreak
Observation of reported household practices
Residual chlorine testing to confirm WaterGuard use

DELETED SLIDES

Background: Outbreak of mystery illness
June 24, 2009: Neno District Health Officer reports
cases of mystery illness to Malawi Ministry of Health
• Cases begin on May 2, 2009
• Rapid spread throughout Neno District, Malawi and neighboring
Tsangano District, Mozambique
• High rate of neurologic complications
• Multinational investigation → Salmonella enterica serovar Typhi
(Typhoid Fever)
September 2010: 784 cases and 44 deaths
• 2 countries, 3 districts, 8 health facilities, and 47 villages
• Case-fatality ratio 5.6%

Background: Response to the outbreak
July 2009 – August 2010
• Community education on Typhoid Fever and household safe
water, sanitation and hygiene practices
• Distribution and education on use of WaterGuard for in-home
stored water treatment
• Construction of boreholes and protected spring boxes in the
most affected villages
• Construction of latrines
• School-based education on hand washing and hygiene
Interventions interrupted by the rainy season
(November 2009 – February 2010)
• Most villages inaccessible

Demographics
All Respondents (n=202)
Mean age (range) 35 (18-83)
Mean number persons per household (range) 5.14 (1-12)
No education 25%
Some primary education 70%
Self-reported literacy 57%

Results: Reported Source of “Typhoid Talks”
100%
(n=111)
80%
Reporting Frequency
60%
40%
20%
63%
27%
16%
0%
Community
Health
Workers
Clinicians NGO's (PSI /
Unicef)
8% 5% 4% 2%
Neighbors /
Family /
Friends
Drama
Performance
Movie
Radio

Results: Reported Causes of Typhoid Fever
100%
(n=202)
Reporting Frequency
80%
60%
40%
73%
47%
27%
20%
7% 7%
14%
0%
Poor hygiene
Drinking bad
water
Eating bad
food
Flies
Unwashed
fruits /
vegetables
Don't know

Results: Reported Methods for Preventing
Typhoid Fever
100%
(n=202)
80%
Reporting Frequency
60%
40%
20%
0%
2%
No
prevention
available
65%
Treat water
50%
Hand
washing
36% 34%
Clean
cooking
utensils /
vessels
Cook food
thoroughly
18%
Wash fruits /
vegetables
7%
Don't know

Results: Primary Source of Household Water
100%
(n=202)
80%
Reported Frequency
60%
40%
20%
48% 46%
0%
4% 2%
Borehole Unprotected well River Public tap

Results: Additional Sources of Household Water
100%
Among Primary Borehole Users (n=84)
80%
Reported Frequency
60%
40%
57%
20%
0%
6%
3%
Unprotected well River Another borehole

Results: Access to Household Stored Water
100%
(n=202)
80%
74%
Reported Frequency
60%
40%
20%
27%
0%
Use a scoop
Pour water