Census, Mapping and Demographic Survey in an Urban Area of Uganda

1
Census, Mapping and Demographic Survey in an
Urban Area of Uganda
Jennifer Davis University of California, San
Francisco, MS4
2
Background

• Malaria remains a significant global health
  problem with 1 million deaths each year in
  sub-Saharan Africa.
• Control is threatened by growing resistance to
  anti-malarial drugs and low utilization of
  prevention measures
• The burden of malaria is best assessed by
  longitudinal cohort studies offering a
  multidisciplinary approach to explore complex
  interactions between host, parasite and the
  environment

3
Background

• Urbanization is occurring rapidly in sub-Saharan
  Africa.
• Differences
• Socioeconomic demographics
• Improved access to diagnosis and treatment
• Lower transmission intensity
• Focal breeding sites
• Variable prevalence rates

• Existing strategies used to control and treat
  malaria may need to be tailored in urban
  environment.

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Census and Survey

• Purpose To create a sampling frame for a
  longitudinal study of malaria incidence and
  combination anti-malarial treatment in urban
  Ugandan children
• (AQSP vs. AQAS vs. Artemether-lumafantrine)
• Provide a detailed characterization of malaria
  risk
• Confer a baseline for future longitudinal studies
  in this community.
• Identify covariates influencing the relationship
  between predictor variables and clinical outcomes
  of malaria incidence and response to therapy.

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Area of Concentration in Global Health

• Finding an excellent mentor ? Grant Dorsey
• Designing Clinical Research course
• Preparing a study proposal ? Census and Survey
• Global Health Area of Concentration core course
• Fifth year extension for research project
• Including travel abroad, data analysis and
  manuscript writing in San Francisco
• Legacy Survey design and two published
  manuscripts
• Optional MD with Thesis

6
Methods

• Description of Study Site
• Malaria is meso-endemic
• Mulago III parish
• Typical urban slum
• Near Mulago Hospital
• Primarily residential, with high population
  density
• Petty commercial activities and small-scale
  subsistence farming

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Census and Survey

• From July to October 2004, a census was conducted
  to generate a sampling frame for recruitment
• Covering the entire parish on foot, all
  households were identified and enumerated

• After verbal consent, a demographic survey was
  administered to collect information on
  inhabitants, home construction and bednet use.

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Mapping the Study Area

• Households were mapped using handheld global
  positioning system receivers linked to pocket
  personal computers.

• Systematically searching the area on foot,
  similar readings were taken for
• - boundaries of parish
• - roads, foot paths
• - mosquito breeding sites
• - health facilities
• - other points of interest

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Population Density 18,824 persons/km2
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Census Results
5171 Households in Mulago III Parish
.
174 (3) Households vacant
4997 Households occupied

66 (1) Households not interviewed 40 (0.8) Not
interested 24 (0.5) No household member gt 18
years2 (0.04) Adult unable to answer
questionnaire

4931 Household occupied and interviewed (16,172
persons)

2176 Households with at least one child lt 10
years of age (4,058 children lt 10 years)
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Census Results

• Median family size 3 persons (1-16)? 40
  inhabited by single or two adult residents
• Median of rooms 1 room (1-17)
• Female 48

K

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Census Results
70
60
Bednet
50
ITN
Bednet Use ()
40
30
20
10
0
lt 1
1 - 5
6 - 10
11 - 17
gt 18
Age (years)

• Among adults, females were significantly more
  likely than males to use a bednet (54 vs. 41,
  Plt0.0001) or ITN (16 vs. 11, Plt0.001)

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Recruitment of Study Participants

• Probability sampling at the level of the
  household was used to to recruit a random sample
  of 600 children aged 1 to 10 years
• From October 2004 to April 2005, experienced home
  visitors conducted door-to-door interviews to
  identify households with at least one child aged
  1 to 10 years
• All children from a single household were
  eligible for enrollment

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Screening of Study Participants

• Eligibility criteria
• Age 1 to 10 years
• Agreement to come to study clinic for any illness
• Agreement to avoid outside medications
• Agreement to remain in Kampala
• Absence of known chronic disease
• No history of side effects to the study
  medications
• Informed consent provided by parent or guardian
• Children underwent a history and physical
  examination
• Blood was collected to determine baseline
  parasitemia and for routine laboratory testing
• Children with weightlt10kg, severe malnutrition,
  life-threatening laboratory results or homozygous
  hemoglobin SS were excluded

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Household Survey

• A detailed survey was administered to the primary
  caregiver of the enrolled child at their home
• Detailed demographic information about study
  participant, primary caregiver, household
• Shaped after standardized surveys (DHS)
• Direct data entry into a into a digitally coded
  form on handheld PDA/computers

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Recruitment
2176 Households with at least one child lt 10
years of age (4,058 children lt 10 years)
Random Sampling
582 Households approached for recruitment
209 (36) Households not eligible for
recruitment 116 (20) No child between ages 1 to
10 years 65 (11) Not interested 28 (5)
Vacant or destroyed home
373 Households with at least one child screened
for enrollment
743 Children screened
51 (9) Households screened with no children
enrolled
142 (19) Children excluded
322 Households with at least one child enrolled
in the study
601 Children enrolled
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Comparison of Eligible and Enrolled Households
and Children
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Description of Enrolled Children
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Multivariate Analysis

• Factors that decreased risk of mild anemia (Hb
  lt11g/dL)
• Increasing age (OR 0.62 for each 1 yr
  increase, 95 CI 0.56-0.68, P lt 0.001)
• Bednet use (OR 0.58, 95 CI 0.38-0.91, P
  0.02)
• Gender, G6PD activity, and sickle cell trait were
  not associated

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Multivariate Analysis

• Factors that decreased risk of parasitemia
• Low G6PD activity (OR 0.33, 95 CI 0.15-0.77, P
  0.009)
• Bednet use (OR 0.64, 95 CI 0.41-0.99, P
  0.045)
• Gender and sickle cell trait were not associated
  with parasitemia
• Increasing age (OR 1.08 for each yr, 95 CI
  1.00-1.17) was associated with a increased risk
  of parasitemia (P 0.06).
• Children who were parasitemic at enrollment were
  much more likely to also be mildly anemic (OR
  3.89, 95 CI 2.28-6.65, P lt 0.001)

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Summary

• Reported net use in this urban area
• Higher than levels commonly reported for rural
  areas
• Higher in children less than five years of age
• Cross-sectional analysis reveals bednet use
  lowers the risk of anemia and parasitemia
• BUTITN use is far below the goal set by African
  leaders at the Roll Back Malaria Summit in Abuja
  in 2000
• Goal 60 of those at risk of malaria, especially
  children under five years of age and pregnant
  women, to have access to ITNs by 2005

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Summary

• Conducting a census in an urban African setting
  provides useful descriptive data and a method for
  recruiting representative cohorts in this
  increasingly important population
• Advantage of GPS
• Benefit of Local Council involvement
• Obstacles smaller urban adult households,
  transient population, lower recruitment
  efficiency
• Need a broad study area and sizeable recruitment
  strategy for population based random sampling for
  pediatric studies in urban areas

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Webale!
AcknowledgementsMU-UCSFGrant DorseySarah
StadekePhil RosenthalSarah KembleDamon Francis