Results of the National Micronutrient Survey in

Malawi

18 June 2003

Overview of presentation

• 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 475Pregnant 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 eventsJuly 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)

23

43.6

33.4

05

101520253035404550

6-11 months 12-23 months 24-36 months

%

Age distribution of school children (n=699)

9-12 years70%

6-8 years30%

Age distribution of women (n=524) and men (n=156)

05

1015202530354045

15-19years

20-29years

30-39years

40-44years

40-49years

50-54years

Women of childbearing age

Men

%

Residence of respondents

88 87 87

12 13 13 10

90

Malawi Northern Central Southern

Rural Urban

Pe r

c en

t ag e

Education of respondents

24

38

25

11

3836

1414

No Education Up to Std 5 Std 6 - 8 Sec & above

Women Men

Per

cen

tage

of

wo m

en a

nd

me n

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

57 5855

36 35 35 37

7 710

4

59

Malawi Northern Central Southern

LowModerateHigh

Pe r

c en

t ag e

of

hou

s eh

o ld s

ANTHROPOMETRY

National Height-for-age Z-score (HAZ)Distribution Curve

-6-5-4-3-2-1012345

z-Score

Reference

%

National data is weighted to account for survey design.

Stunting by region

12.5

28.7

19.623

38.9

54.1 55.6 53.4

Northern Central Southern National

<-3 SD <-2 SD

Hei

ght-

for-

age

Z-s

core

pre

vale

nce

%

National Weight-for-height Z-score (WHZ) Distribution Curve

0

5

10

15

20

25

-5-4-3-2-1012345

z-Score

%

Reference

National data is weighted to account for survey design.

Weight-for-height <-2 Z-scoreby region

3.4

1.1

8.6

4.7

0

2

4

6

8

10

12

NorthCentral

South

National

%

Weight-for-age Z-score (WAZ) by Age

11.48.9

4.9

29.833.8

28.6

0

5

10

15

20

25

30

35

40

6-11 months 12 - 23 months 24 - 36 months

<-3 SD<-2 SD

%

Summary of anthropometry results for preschool children

23

8

0

53

31

5

STUNTING(HAZ)

UNDERWEIGHT(WAZ)

WASTING(WHZ)

<-2 SD

<-3 SD

Percentage of children 6-36 months

Body Mass Index for non-pregnant women of childbearing age

6.7

82.8

8.12.4

0

10

20

30

40

50

60

70

80

90

<18.5 18.5 - 24.9 25.0-29.9 >30.0

%

Body Mass Index

MORBIDITY

Prevalence of malaria parasitemia by target group

60.1

47.4

18.7 16.712.2

0

10

20

30

40

50

60

70

Preschoolchildren

Schoolchildren

Pregnantwomen

Non-pregnantwomen

Men

%

National data is weighted to account for survey design.

Mosquito bednet knowledge and use by SES

0102030405060708090

100

Low SES Moderate SES High SES National

Heard of bednetUse bednet

%

Prevalence of intestinal parasites and urinary schistosomiasis among school children (6-12 y)

0

5

10

15

20

25

30

Hookworm Roundworm Schistosomamansoni

Urinaryschistosomiasis

%

FOOD CONSUMPTIONRESULTS

• Breastfeeding results

• Fortification Rapid Assessment Tool (FRAT) - 24 hour dietary recall results

Breastfeedingfor preschool children >12 months

EXCLUSIVE BREASTFEEDING• Age when child given anything other than breastmilk

– Less than six months 53.1%– Greater or equal to 6 months 46.9%

DURATION OF BREASTFEEDING• Age when stopped breastfeeding

– Less than 12 months 4.3%– Greater or equal to 12 months 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

05

101520253035404550

Preschool children(n=157)

Women (n=165) Men (n=161)

%SugarOilMaize flourComplementary foods

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

0

10

20

30

40

50

60

70

80

90

100

Preschool children(n=157)

Women ofchildbearing age

(n=165)

Adult men (n=161)

%

Previous day

Past 7 days

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

59.2

38.3

57.4

38.0

0

10

20

30

40

50

60

70

Preschoolchildren (n=476)

School children(n=603)

Women ofchildbearing age

(n=464)

Adult men(n=135)

%

Note: Cut-offs for VAD were <20mcg/dL for all subjects

Vitamin A Supplementation IntakePreschool 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*

0102030405060708090

100

6-11.9 mos 12-23.9 mos 24-35.9 mos

%

<= 6mos since last dose <=12 months since last dose

*Among children who received a vitamin A supplement at least once

National Vitamin A supplementation resultsWomen 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

79.7

22.327

13

0102030405060708090

Preschoolchildren

Schoolchildren

Non-pregnantwomen

Men

%

Anemia Stratified by Malaria Parasitemia Status

91

27.2

40.1 41.5

21

62.5

17.924.3

17.6 16.9

0102030405060708090

100

Preschoolchildren

Schoolchildren

Non-pregnant

WCBA

Pregnantwomen

Men

%

With malaria

No malaria

Prevalence of iron deficiency by target group

0

10

20

30

40

50

60

70

Preschoolchildren

Schoolchildren

Non-pregnantwomen

Men

%

ZincProtoprophyrin

Transferrinreceptor

Prevalence of iron deficiency anemia by target group

0

10

20

30

40

50

60

70

Preschoolchildren

Schoolchildren

Non-pregnantwomen

Men

%

Hemoglobin & Zinc Protoporphyrin

Hemoglobin & Transferrin receptor

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 supplements90.2% daily2.8% regularly1.5% weekly

SUMMARY OF FINDINGS

Summary of findings - Preschool children

0102030405060708090

100Infectious

illness

Micronutrient deficiencies

Anthropometry

%

Summary of findings – School children

0102030405060708090

100

Malar

ia

Hookw

orm

Roun

dwor

m

Schistos

oma man

soni

Urinar

y sc

histos

omiasis

Vita

min A

defi

cienc

y

Anem

ia

Iron

defi

cien

cy (Z

P)

Iron

defi

cien

cy (T

fR)

Infectious illness Micronutrient deficiencies

%

Summary of findings Non-pregnant women of childbearing age

0102030405060708090

100

Malar

ia

Vita

min A defi

cien

cy

Anem

ia

Iron

defi

cienc

y (Z

P)

Iron

defi

cienc

y (T

fR)

Low BMI (

<18.5)

Overw

eigh

t (25

-30)

Obese

(>30

)

Infectious illness

Micronutrient deficiencies

%

Anthropometry

Summary of findings - Men

0102030405060708090

100

Malar

ia

Vita

min A defi

cien

cy

Anem

ia

Iron

defi

cienc

y (Z

P)

Iron

defi

cienc

y (T

fR)

Infectious illness

Micronutrient deficiencies%

Zikomo kwambiri!!!