Results of the
National Micronutrient Survey in
Malawi
18 June 2003
Overview of presentation
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Background and objectives
Methods
Demographics
Anthropometry
Morbidity
Food consumption
Iodine
Vitamin A
Anemia and iron deficiency
Summary findings
BACKGROUND AND
OBJECTIVES
Purpose of National Survey
• Data for Advocacy
– Existing data was clinical and localized
– Government of Malawi in process of creating sector
investment programs and poverty reduction strategies
– Need national data to make micronutrient interventions a
national priority
• Baseline for monitoring
– Need information to support for future MN interventions,
especially for fortification
• Support future communication efforts
• Capacity building
Survey Objectives
• To determine the prevalence of vitamin A deficiency
as a public health problem in target groups
• To determine the prevalence and nature of anemia
with respect to iron deficiency, parasites and
infections as a public health problem in target groups
• To determine the magnitude of iodine deficiency
among primary school aged children as a proxy for
the total population
• Validate the identified food vehicles for fortification
and estimate levels of consumption
METHODS
Sampling
• Nationally and regionally
representative
– Northern
– Central
– Southern
• Stratified sampling: 30 clusters
per region = 90 clusters
• Randomly selected clusters
• Included 26 of the 27 districts
Household and school based survey
• 18 households per cluster
• 540 households per
region
• 1,620 households
nationally
• 90 schools (1 per cluster)
Target Groups
• Preschool children (6-36 months)
• School children (6-12 years)
• Women of childbearing age
(15-45 years)
• Men (20-55 years)
Total sample by target group
Preschool children
548
School children
701
Women of childbearing age
Non-pregnant
Pregnant
475
57
Men
161
Vitamin A and Iodine Indicators
• Vitamin A
– Serum retinol
• Iodine
– Test household salt
– Salt titration
– Urinary iodine
Anemia and Iron Deficiency
Indicators
• Hemoglobin (Hb)
• Zinc protoporphyrin (ZP)
• Transferrin receptor (TfR)
Parasitic infection indicators
• Malaria
• Urinary schistosomiasis
• Intestinal parasites
–Hookworm
–Roundworm
–Schistosoma mansoni
General Household Questionnaire
• Demographics & socioeconomic status
• Knowledge of anemia, vitamin A and iodized
salt
• Breastfeeding history
• Supplementation
• Health history
• Consumption of centrally processed foods
Fortification Rapid Assessment Tool
(FRAT)
• National sample only
• Targeted 24 hour dietary recall
• Centrally processed staple foods
– Sugar
– Oil
– Maize flour
– Complementary food
• Quantity consumed to set levels of
fortification
Biological Sample Collection Procedures
• Malaria thick smears
• Microtainers to collect capillary blood samples
–
–
–
–
Hemoglobin with HemoCue
Whole blood for biochemical analysis
Dried blood spots
Spun down blood for serum
• Stool samples for intestinal parasites
(school children only)
• Urine sample for iodine and urinary
schistosomiasis (school children only)
Other Collection Procedures
• Height and weight
measurements on
preschool children
and women
• Household salt
samples for iodine
content
Sequence of events
July 2001
• Community mobilization
• Enumeration of households
• Development, translation & pre-testing of questionnaires
Sept/Oct 2001
• Training and field testing for survey
• Fieldwork: 6 teams for 3-4 weeks
• Data entry
Forever
• Analysis of data and lab specimens – Nov 2001 – Nov 2002
• Final report & dissemination meeting – May 2003
• 5 year action plan – May 2003
DEMOGRAPHICS
•Age and Sex
•Residence – urban and rural
•Formal Education
•Socioeconomic status index
Age distribution of
preschool children (n=527)
%
50
45
40
35
30
25
20
15
10
5
0
43.6
33.4
23
6-11 months
12-23 months
24-36 months
Age distribution of
school children (n=699)
6-8 years
30%
9-12 years
70%
Age distribution of
women (n=524) and men (n=156)
Women of childbearing age
%
45
40
35
30
25
20
15
10
5
0
Men
15-19
years
20-29
years
30-39
years
40-44
years
40-49
years
50-54
years
Residence of respondents
Rural
88
87
Urban
90
87
12
13
13
10
Malawi
Northern
Central
Southern
Education of respondents
Women
38
Men
38
36
25
24
14
11
No Education
Up to Std 5
Std 6 - 8
14
Sec & above
Socioeconomic status (SES) Index
• Composite index composed from household
data on:
– cooking fuel
– water source
– sanitary facilities
– material of roof and floor
– number of rooms
– ownership of various assets
• Sufficient information was available for 90%
of the sample.
Index of socioeconomic status
58
57
36
7
Malawi
59
55
35
37
35
7
Northern
Low
Moderate
High
10
4
Central
Southern
ANTHROPOMETRY
National Height-for-age Z-score (HAZ)
Distribution Curve
Reference
z-Score
-6
-5
-4
-3
-2
-1
0
1
2
3
0
5
10
%
15
20
25
National data is weighted to account for survey design.
4
5
Height-for-age Z-score prevalence %
Stunting by region
<-3 SD
<-2 SD
54.1
55.6
53.4
38.9
28.7
19.6
23
12.5
Northern
Central
Southern
National
National Weight-for-height Z-score (WHZ)
Distribution Curve
z-Score
Reference
-5
-4
-3
-2
-1
0
1
2
3
4
0
5
%
10
15
20
25
National data is weighted to account for survey design.
5
Weight-for-height <-2 Z-score
by region
12
10
8.6
8
%
6
4
4.7
3.4
1.1
2
0
l
na
al
th
io
at
N
u
So
th
tr
en
C
or
N
Weight-for-age Z-score (WAZ) by
Age
%
40
33.8
35
29.8
30
28.6
25
<-3 SD
<-2 SD
20
15
11.4
10
8.9
4.9
5
0
6-11 months
12 - 23 months 24 - 36 months
Summary of anthropometry
results for preschool children
WASTING
(WHZ)
5
<-2 SD
0
<-3 SD
UNDERWEIGHT
(WAZ)
STUNTING
(HAZ)
31
8
53
23
Percentage of children 6-36 months
Body Mass Index for non-pregnant
women of childbearing age
%
90
82.8
80
70
60
50
40
30
20
10
8.1
6.7
2.4
0
<18.5
18.5 - 24.9
25.0-29.9
Body Mass Index
>30.0
MORBIDITY
Prevalence of malaria parasitemia by
target group
%
70
60
50
60.1
47.4
40
30
20
10
18.7
16.7
Pregnant
women
Nonpregnant
women
12.2
0
Preschool
children
School
children
Men
National data is weighted to account for survey design.
Mosquito bednet knowledge and use
by SES
Heard of bednet
Use bednet
%
100
90
80
70
60
50
40
30
20
10
0
Low SES
Moderate SES
High SES
National
Prevalence of intestinal parasites and urinary
schistosomiasis among school children (6-12 y)
30
25
%
20
15
10
5
0
Hookworm
Roundworm
Schistosoma
mansoni
Urinary
schistosomiasis
FOOD CONSUMPTION
RESULTS
• Breastfeeding results
• Fortification Rapid Assessment Tool (FRAT)
- 24 hour dietary recall results
Breastfeeding
for preschool children >12 months
EXCLUSIVE BREASTFEEDING
• Age when child given anything other than breastmilk
– Less than six months
– Greater or equal to 6 months
53.1%
46.9%
DURATION OF BREASTFEEDING
• Age when stopped breastfeeding
– Less than 12 months
– Greater or equal to 12 months
4.3%
95.7%
Fortification Rapid Assessment Tool
(FRAT) Methods
• Validated FRAT through cooking
exercise with group of women to
determine standards
– Portion sizes
– Average quantities for household utensils
– Standard recipes
Consumption of centrally processed
staple foods
Sugar
Oil
Maize flour
Complementary foods
%
50
45
40
35
30
25
20
15
10
5
0
Preschool children
(n=157)
Women (n=165)
Men (n=161)
SUGAR
• 61.2% usually have sugar in the house
• Average consumption varied by group:
45 grams for preschool children, 68
grams for women and 54 grams for men
• Sugar is consumed in all seasons by
children (47.8%), women (41.7%), and
men (35.4%)
Sugar Consumption
100
90
Previous day
80
70
60
% 50
Past 7 days
40
30
20
10
0
Preschool children
(n=157)
Women of
childbearing age
(n=165)
Adult men (n=161)
COOKING OIL
• Half (50.3%) the women interviewed usually cook
with oil
• Similar average amount consumed by children
(3.7 g), women (3.8g) and men (4.3g)
• In the past 7 days, children (52.4%), women
(56.1%) and men (61.5%) ate food with oil
• Oil was consumed in all seasons by 41.7% of
children, 41.5% of women and 35.4% of men
IODINE RESULTS
Rapid Test Kit Results
• Qualitative results – color change
• 1461 households surveyed
• 86.1% salt available
• 91.7% some iodine
• least likely to have salt available for
testing
– lower SES households
– households in southern region
Household Salt Titration Results
(n=510)
• 77.6% of salt samples contained
some iodine (>0 ppm)
• 47.1% contained 15 ppm
• International standard
• 36.7% contained 25 ppm
• Southern African standard
VITAMIN A RESULTS
National prevalence of vitamin A deficiency by
target group
70
60
59.2
57.4
50
40
%
38.3
38.0
Preschool
School children
Women of
children (n=476)
(n=603)
childbearing age
(n=464)
Adult men
(n=135)
30
20
10
0
Note: Cut-offs for VAD were <20mcg/dL for all subjects
Vitamin A Supplementation Intake
Preschool children (n=540)
• 64.4% ever received supplement in
last 6 months
• 85.4% one dose in the last 12months
Months since last vitamin A supplement by
age group*
100
90
80
70
60
% 50
40
30
20
10
0
6-11.9 mos
<= 6mos since last dose
12-23.9 mos
24-35.9 mos
<=12 months since last dose
*Among children who received a vitamin A supplement at least once
National Vitamin A supplementation results
Women of childbearing age (n=427)
• 34.9% received a supplement within 2
months of their last delivery
• Women with higher education were
more likely to report having received a
vitamin A supplement
ANEMIA AND IRON DEFICIENCY
Prevalence of anemia by target group
%
90
80
70
60
50
40
30
20
10
0
79.7
22.3
27
13
Preschool
children
School
children
Non-pregnant
women
Men
%
Anemia Stratified by Malaria
Parasitemia Status
100
90
80
70
60
50
40
30
20
10
0
91
With malaria
No malaria
62.5
40.1
Preschool
children
27.2
17.9
24.3
School
children
Nonpregnant
WCBA
41.5
17.6
Pregnant
women
2116.9
Men
Prevalence of iron deficiency by target
group
Zinc
Protoprophyrin
70
60
Transferrin
receptor
%
50
40
30
20
10
0
Preschool
children
School
children
Non-pregnant
women
Men
Prevalence of iron deficiency anemia
by target group
70
Hemoglobin & Zinc Protoporphyrin
60
Hemoglobin & Transferrin receptor
%
50
40
30
20
10
0
Preschool
children
School
children
Non-pregnant
women
Men
Use of iron supplements
• Pregnant women
– 46.3% were taking iron supplements
• Non-pregnant women
– 7.0% were taking iron supplements
• Frequency of taking iron supplements
90.2% daily
2.8% regularly
1.5% weekly
SUMMARY OF FINDINGS
Summary of findings - Preschool children
Vi
ta
m
Anthropometry
St
un
ti
U
ng
nd
er
w
ei
gh
t
W
as
ti
ng
in
A
M
Micronutrient deficiencies
de
fic
ie
nc
y
Ir
on
An
de
em
fic
ia
Ir
ie
on
nc
y
de
(Z
fic
P)
ie
nc
y
(T
fR
)
Infectious
illness
al
ar
ia
100
90
80
70
60
% 50
40
30
20
10
0
M
al
ar
H
ia
oo
kw
Sc
or
R
ou
hi
m
st
n
dw
os
U
ri
om
or
na
m
a
ry
m
sc
an
hi
so
st
ni
os
om
ia
Vi
si
ta
s
m
in
A
de
fic
ie
nc
Ir
on
y
A
de
ne
fic
Ir
m
on
ia
ie
n
de
cy
fic
(Z
ie
P)
nc
y
(T
fR
)
Summary of findings – School children
100
90
80
70
60
% 50
40
30
20
10
0
Infectious illness
Micronutrient
deficiencies
Summary of findings
Non-pregnant women of childbearing age
Micronutrient
deficiencies
Infectious
illness
Vi
ta
m
in
A
de
f
M
ic
ie
nc
y
Ir
on
An
de
em
fi
ia
ci
Ir
en
on
cy
de
(Z
fi
ci
P)
en
cy
(T
fR
)
Lo
w
BM
O
I
ve
(<
rw
18
ei
.5
gh
)
t
(2
530
O
be
)
se
(>
30
)
Anthropometry
al
ar
ia
100
90
80
70
60
% 50
40
30
20
10
0
Summary of findings - Men
fR
)
de
fi
ci
en
cy
ci
en
cy
de
fi
(T
ia
Ir
on
de
f
A
in
Vi
ta
m
An
em
ic
ie
nc
y
al
ar
ia
M
(Z
P)
Micronutrient
deficiencies
Infectious
illness
Ir
on
100
90
80
70
60
% 50
40
30
20
10
0
Zikomo kwambiri!!!