DEMOGRAPHIC

AND

HEALTH

RESEARCH

DHS WORKING PAPERS

2010 No. 74

Olufunke A. Fayehun

October 2010

This document was produced for review by the United States Agency for 

International Development.

Household Environmental Health Hazards 

and Child Survival in Sub-Saharan Africa
The DHS Working Papers series is a prepublication series of papers reporting on research in progress that 

is based on Demographic and Health Surveys (DHS) data. This research is carried out with support 

provided by the United States Agency for International Development (USAID) through the MEASURE 

DHS project (#GPO-C-00-08-00008-00). The views expressed are those of the authors and do not 

necessarily reflect the views of USAID or the United States Government. 

MEASURE DHS assists countries worldwide in the collection and use of data to monitor and evaluate 

population, health, and nutrition programs. Additional information about the MEASURE DHS project can 

be obtained by contacting MEASURE DHS, ICF Macro, 11785 Beltsville Drive, Suite 300, Calverton, 

MD 20705 (telephone: 301-572-0200; fax: 301-572-0999; e-mail: reports@measuredhs.com; internet: 

www.measuredhs.com).
Household Environmental Health Hazards and Child Survival 

in Sub-Saharan Africa 

Olufunke A. Fayehun 

ICF Macro 

Calverton, Maryland, USA 

October 2010 

Corresponding author: Olufunke A. Fayehun, Department of Sociology, University of Ibadan, Nigeria; E-mail:

funke.adesanmi@mail.ui.edu.ng 
ACKNOWLEDGEMENT 

The author wishes to thank Shea Rutstein, Fred Arnold, Sunita Kishor and other MEASURE 

DHS reviewers for their comments on the draft manuscript. The constructive comments of 

Ayorinde Fayehun, Uche Isiugo-Abanihe, Ezenwa Nwokocha and Obafemi Omololu are also 

appreciated. 

Suggested citation: 

Fayehun, Olufunke A. 2010. Household Environmental Health Hazards and Child Survival in 

Sub-Saharan Africa. DHS Working Papers No. 74. Calverton, Maryland, USA: ICF Macro.
ABSTRACT 

Most deaths of children under age five in sub-Saharan African and other developing 

countries have been linked to the household environment. This study, therefore, hypothesized 

that variations in household environments among sub-Saharan countries could affect children’s 

survival chances. Using secondary data from Demographic and Health Surveys (DHS) in eight 

sub-Saharan countries, the study broadly categorized the selected countries into low and high 

under-five mortality groups. The study found that high-mortality countries are at a relative 

disadvantage on basic household environmental variables. There are significant relationships 

between the household environment and child survival. Some of the differences in childhood 

morbidity and mortality between low and high under-five mortality countries can be explained 

by levels of household environmental health hazards and by maternal socioeconomic status. 

1

INTRODUCTION

This study systematically examines health hazards within the household environment as 

they affect child survival chances across sub-Saharan Africa. The distinctive physiological nature 

of children under age five predisposes them to a variety of health hazards within and around the 

household, including unsafe sources of water and poor sanitary conditions. Thus providing safe 

drinking water and access to improved sanitation within the household environment can reduce 

the risk of mortality and morbidity among children under age five (WHO, 2009). This fact has 

been demonstrated in some developed countries, where childhood mortality has declined through 

interventions such as the provision of safe drinking water and adequate sanitary facilities 

(Rutstein, 2000). Although some parts of the developing world are in the process of achieving 

substantial lower childhood mortality due to such interventions, the situation remains critical in 

sub-Saharan Africa, where about half of the population has no access to safe drinking water and 

improved sanitation (WHO, 2009). 

Literature Review 

Decline in under-five deaths in Africa has been slow, despite various approaches to 

improving child health (WHO, 2005). Although there are large variations across regions and 

countries in the developing world, mortality rates among children under age five in African 

countries are higher compared with other less developed societies. Out of 20 countries identified 

as having high under-five mortality, 19 are in sub-Saharan Africa (United Nations, 2002; 

Mutunga, 2004; Balk et al, 2004; Mason, 2004; WHO, 2005). 

In developing countries maternal, demographic, and socioeconomic factors have been 

found to be important determinants of childhood mortality (Mosley and Chen, 1984; Mutunga, 

2007; Rutstein, 2000; Gyimah and Fernando, 2002). Nutritional deficiencies, illnesses such as 

malaria, diarrhea, and acute respiratory infection (ARI), as well as vaccine-preventable diseases 

are also recognized as causes of under-five mortality in most countries in sub-Saharan Africa 

(Caldwell, 1979; Boerma and Bicego, 1992; Rutstein, 2000; Gyimah, 2002). Adetunji (2000) 

also observed a reversal of improvements in under-five mortality in countries with very high 

adult HIV prevalence (greater than 5%); mortality rates among children of HIV-positive mothers 

are much higher, by two to five times, than among children of HIV-negative mothers. 
2

Most of the factors identified from various studies on childhood mortality in developing 

countries have followed the Mosley and Chen (1984) framework, which is based on the idea that 

the factors that affect childhood mortality work through a set of "proximate determinants." Five 

other premises were also suggested, along with the basic premises: (i) under optimal conditions, 

child survivability rates for newborn infants can be expected to reach 97 percent; (ii) in the real 

world, this rate is lowered by social, economic, biological, and environmental factors; (iii) 

socioeconomic determinants must operate through the proximate determinants in order to 

influence disease and disease processes; (iv) the proximate determinants can be indicated by the 

diseases and deficiencies of the surviving population; (v) child mortality is the result of the 

cumulative consequences of multiple disease processes. 

Proximate determinants, as defined by Mosley and Chen (1984), are divided into five 

categories: maternal and demographic factors; environmental health factors; nutrient deficiency; 

injury; and personal illness control. Maternal factors include age of the mother, parity, and birth 

interval. The demographic factors include sex of child, multiple births, and previous child death. 

Household environmental factors include the house’s construction material, sources of water, 

and presence/types of toilet facilities, as well as cooking facilities. In addition to the proximate 

determinants, Mosley and Chen posit that socioeconomic factors also affect childhood mortality. 

Manda (1999), however, has observed that the effect of the socioeconomic variables becomes 

greater as the child gets older. 

Although several factors are responsible for the survival of children under age five in 

developing countries, studies reveal that some childhood diseases that often result in mortality 

can be explained by well-known health hazards within the child’s household environment 

(Rutstein, 2000; United Nations, 2001). Indeed, environmental health hazards are threats to the 

health of millions of people in the settings where they live (World Bank, 2000; UNICEF, 2001). 

A variety of health hazards, including poor air quality, poor building standards, and 

contamination of water and food are present in the household environment (Racioppi, 2002). 

Studies have shown that sanitation, water supply, and hygiene are generally poor in developing 

countries; more than 1 billion people live without adequate shelter, about 1.4 billion people lack 

access to safe water, and over 2.9 billion people have no access to adequate sanitation (World 

Resources Institute, 1999; Rutstein, 2000; WHO, 2005; WHO, 2009). 
3

Children under age five are in the dynamic stage of growth. Their immune, respiratory, 

and digestive systems are still developing. The impact of an unhealthy environment is felt among 

them because they are always close to the ground, where many contaminants settle (WHO, 2003; 

Mutunga, 2004). Unlike more developed countries, where health hazards from the child’s 

household environment constitute little risk and hence cause little childhood mortality, 

developing countries still experience high childhood mortality due to diseases associated with 

poor water supply, sanitation, and personal and household hygiene (Woldemicael, 2000; 

Rutstein, 2000). The World Health Organization (WHO) (2003) reported that 75% of deaths 

from acute respiratory infections occur before the first birthday, and one-quarter of deaths among 

children under age five are linked to diarrhea. Studies in some developing countries have found a 

significant incidence of diarrheal diseases because of water shortage and contamination, early 

exposure to measles infections because of household crowding, and high risks of accidents or 

injury because of poor housing (Brockerhoff, 1995; Yassin, 2000; Macassa et al, 2004; Murray 

et al, 2007). 

Women and young children are at high risk of exposure to the smoke emitted from 

burning coal, firewood, and other sources of fuel, due to women’s traditional role in food 

preparation. Also, rapid urban growth often has outpaced the provision of safe water and 

sanitation, with crowded living conditions facilitating the spread of diseases that can affect child 

survival (Rutstein, 2000, Mishra and Retherford, 2007). Timaeus and Lush (1995) found that 

child morbidity and mortality have been strongly associated with household environmental 

conditions in urban areas of Ghana, Egypt, Brazil, and Thailand. 

Children in sub-Saharan Africa, as in other developing countries, are vulnerable to these 

health hazards from their household environment. According to World Health Statistics 2009 

(WHO, 2009), the regional average of the under-five mortality rate (145 deaths per 1,000 live 

births) falls short of World Summit for Children national goal of reducing the infant mortality 

rate to 50/60 deaths per 1,000 live births, and reducing under-five mortality to 70/80 per 1,000. 

Although some countries within sub-Sahara Africa have reached this goal, others still lag behind. 

This study, therefore, examined differences in the household environmental health hazards 

between low and high under-five mortality countries, and their subsequent effect on child 

survival. 
4

DATA AND METHODS 

This comparative study examines secondary data from Demographic and Health Surveys 

(DHS) conducted between 2003 and 2008 in eight selected sub-Saharan African countries. The 

surveys provide up-to-date information on population and health in more than 80 countries. The 

DHS samples include data on birth history, household characteristics, health service usage, and 

child health, based on information collected from women at the time of the survey. The 

individual women’s questionnaire was used to collect information from all women age 15-49. 

Birth files were generated from the eligible women’s responses on their birth history. 

The focus of this study is on how the differences in under-five mortality can be explained 

by household environments. Therefore, the selection for this study of eight countries is based on 

two criteria: the World Health Statistics 2003 to 2009 under-five mortality rates, and DHS 

surveys conducted between 2003 and 2008. Four of the selected countries are among the 2009 

World Health Statistics countries with the lowest under-five mortality rates, while the other four 

countries are among those with the highest under-five mortality rates in sub-Saharan Africa. The 

selected period was recent enough to ensure that household characteristics do not differ widely 

from current situations. Also, births in the five years preceding the survey and births to mothers 

who are de jure1

 residents of the household were selected for study. Table 1 shows the 

breakdown of the selected low and high under-five mortality countries, with the number of 

sampled women and births within the five years preceding the survey2. 

 

1 De jure residents are the usual residents in the household 

2

 Information about detailed sampling procedures are in the individual country reports and can be requested/ordered 

from www.measuredhs.com 
5

Table 1: Sample breakdown of the selected countries by region, U5 mortality rate and DHS year

Country Region

WHO 

statistics U5 

mortality rate

DHS recent 

survey year

Sampled 

women

Sampled 

births

DHS Births to de 

jure resident 

within 5yrs 

preceding survey

Low childhood mortality countries

Namibia Southern 68 2007 9,804 19,522 4,783

Lesotho Southern 84 2004 7,095 14,708 3,464

Zimbabwe Southern 90 2006 8,907 19,489 5.087

Swaziland Southern 91 2006 4,987 11,410 2,730

High childhood mortality countries

Niger West 176 2006 9,223 34,378 9,830

Nigeria West 189 2008 33,385 104,808 27,898

Burkina Faso West 191 2003 12,477 41,520 10,667

Mali West 196 2006 14,583 52,140 14,308

Source: DHS and World Health Statistics (2009)

Variable Measurement 

The dependent variables for this study are under-five mortality and recent childhood 

morbidity. Childhood mortality is measured by the mother’s response on whether a child born in 

the last five years is alive or dead. Childhood morbidities are measured by the occurrence of 

symptoms of diarrhea, fever, and acute respiratory infection (ARI) within two weeks preceding 

the survey. The household environmental variables include sources of drinking water, time to 

water source, types of toilet facilities, main flooring material of the household, type of cooking 

fuel, and use of mosquito nets in the household. The socioeconomic factor is measured with 

variables such as the mother’s highest educational level, father’s highest educational level, rural 

or urban residence, and household wealth index. The key variables were re-categorized from 

DHS data for this study. 

Dependent Variables 

 Childhood mortality (Yes, No) - 

Response to question: Child is alive? 
6

 Childhood diarrhea (Yes, No) - 

Response to question: Had diarrhea in the last 2 weeks? 

 Fever (Yes, No) - 

Response to question: Had fever in the last 2 weeks? 

 ARI (Yes, No) - 

Response to questions: Had cough and had short rapid breathing in the last 2 weeks? 

Socioeconomic Variables 

 Mother’s highest educational level (None, Primary, Secondary, Tertiary) 

 Father’s highest educational level (None, Primary, Secondary, Tertiary) 

 Residence (Urban, Rural) 

 Wealth index (Low, Middle, High) 

Low – lowest and second quintiles; high – highest and fourth quintiles 

Household Environment Variables 

Source of drinking water: 

(1) Piped water - piped into dwelling; piped into yard/plot; public tap or standpipe 

(2) Other improved sources - protected dug well; protected spring; bottled water; 

rainwater; tube well/borehole 

(3) Unprotected dug well 

(4) Other unimproved sources - unprotected spring; cart with small tank/drum; tankertruck; surface water 

Time to water source: Regrouped from actual values in minutes to 

(1) On premises 
7

(2) Less than 15 minutes 

(3) 15-29 minutes 

(4) 30 minutes and above 

Toilet facility: 

(1) Improved flush - flush to piped sewer system; flush to septic tank; flush/pour flush to 

pit 

(2) Other improved facility - composting toilet; VIP latrine; pit latrine with a slab 

(3) Unimproved facility - flush/pour flush elsewhere; pit latrine without a slab/open pit; 

bucket; hanging toilet 

(4) No facility, or bush

Disposal of child’s feces: 

(1) Sanitary disposal - child used toilet/latrine; feces put/rinsed into toilet or latrine; 

feces buried; used disposable diapers; used washable diapers 

(2) Unsanitary disposal - feces put/rinsed into drain or ditch; thrown into garbage; 

rinsed away; left in the open 

Type of flooring material: 

(1) Finished - parquet; polished wood; vinyl/ asphalt strips; ceramic tiles; cement; 

carpet 

(2) Rudimentary - wood plank; bamboo 

(3) Natural - earth; sand; dung 

Type of cooking fuel: 

(1) Biomass fuel - wood; crop residue/dung cake; straw; lignite; charcoal 

(2) Non-biomass fuel - electricity; LPG; biogas; kerosene

Use of mosquito net for children under five years: (Yes, No) 
8

Furthermore, an index of the status of household environmental health hazards is derived 

from the responses on some household environmental factors. The household environmental 

health hazard variable is defined below. 

i. Source of drinking water: 

Improved source of drinking water (scored 1) 

Unimproved source of drinking water (scored 0) 

ii. Time to get to water source: 

 On premise or less than 30 minutes (scored 1) 

30 minutes and more (scored 0) 

iii. Type of toilet facility: 

Improved sanitation facility (scored 1) 

Unimproved sanitation facility and no facility (scored 0) 

iv. Main flooring material: 

Finished flooring (scored 1) 

Natural and rudimentary flooring (scored 0) 

v. Type of cooking fuel: 

Non-biomass fuel (scored 1) 

Biomass fuel (scored 0) 

The sum of the scores was further categorized into: non- health hazard (scored 5=2), low 

health hazard (scored 3-4= 1) and high health hazard (scored 0-2 = 0). 

The analysis involved the use of descriptive statistics to examine the distribution of 

household environmental health hazards in each country. Percentage distribution tables and 

graphs were used to provide a general overview of the different socioeconomic and demographic 

variables, household environment, and health hazards categories after weighing the samples. The 
9

Kaplan-Meier method was used to estimate risk of childhood mortality by household 

environmental health hazards. This is a descriptive procedure for examining the distribution of 

time to an event variable; separate analyses by levels of a stratification variable were compared 

across the countries. The Cox proportional hazard model was further used to understand the 

effects of household environmental health hazard on childhood mortality in the selected 

countries. Various studies have shown that the Cox model gives estimates consistent with those 

produced by the logistic model and the more restricted hazard model. This proportional hazard 

model assumes that the underlying hazard rate is a function of the independent variables 

(covariates). 
10

RESULTS AND DISCUSSION

Patterns of Household Environmental Health Hazards 

The physiological characteristics of children place them at risk of death due to an 

unhygienic household environment. Therefore, this study examined the patterns of household 

environmental health hazards in the selected sub-Saharan countries. There are differences in the 

sources of drinking water for the eight selected countries, shown in Table 2. In countries with 

low under-five mortality, as in Namibia and Lesotho, the proportion of children living in 

households with an improved source of drinking water is greater than in countries in the high 

under-five mortality group. In Namibia, 71% of households, and in Lesotho 55% of households, 

access their drinking water from improved sources (piped, covered well, or borehole). 

Conversely, in countries with high under-five mortality at least 40% of children live in 

households with an open well or surface water as their source of drinking water. 

The source of drinking water has a profound implication for the health outcomes of both 

mother and child. Improved sources of drinking water are less likely to be contaminated, while 

other sources, such as surface water and open wells, are more likely to carry disease-causing 

agents (NPC, 2004). The finding from this study corroborates several reports in developing 

countries on the relationship between household source of drinking water and childhood 

mortality; children under age five in households relying on open well/surface water have higher 

risks of death than those with piped water/borehole or covered well (Rutstein, 2000; Policy 

Project/Nigeria, 2002). 

Although the source of water may be improved and made hygienic, timely access to the 

water is also very important. If the source of the water is more than 15 minutes away from the 

household, there may not be sufficient water from that source, and unsafe water might be 

consumed at times. The time to source of drinking water examined among the selected countries 

shows that at least half of children under age five in Namibia, Zimbabwe, Swaziland, Nigeria, 

Burkina Faso, and Mali live in households with access to drinking water on the premises or 

within 15 minutes of the household. Conversely, in Niger more than 50% of children live in 

households that fetch their drinking water from a source more than 15 minutes away. 
Table 2: Household environment in sub-Saharan African countries with low and high levels of under-five mortality

Household environment 

variables

Low mortality countries High mortality countries

Namibia Lesotho Zimbabwe Swaziland Average Niger Nigeria

Burkina 

Faso Mali Average

Source of drinking water

Piped water 71.0 54.8 34.1 49.0 52.2 20.1 9.5 13.2 23.3 16.5

Other improved source 14.5 20.8 38.1 15.6 22.3 19.2 42.8 44.5 31.2 34.4

Unprotected dug well 4.0 22.1 16.1 10.7 13.2 59.2 23.0 28.5 41.6 38.1

Other unimproved source 10.5 2.3 11.7 24.6 12.3 1.6 24.6 13.9 3.9 11.0

Number of children 4,784 3,464 5,087 2,731 9,830 27,886 10,667 14,308

Time to water source

On premises 47.7 9.0 40.0 33.2 34.4 13.3 26.4 21.6 45.5 30.5

Less than 15 minutes 22.9 32.9 15.5 26.2 23.3 27.7 32.2 31.3 38.7 33.7

15-29 minutes 9.7 19.6 14.7 11.0 13.6 20.5 18.3 19.9 10.1 15.8

30 minutes or more 19.7 38.5 29.8 29.6 28.7 38.5 23.3 27.2 5.7 20.1

Number of children 4,720 3,455 5,071 2,724 15,971 9,804 27,574 10,643 14,289

Toilet facility

Improved flush toilet 32.2 1.0 28.5 12.5 17.3 0.8 12.8 1.2 1.6 3.6

Other improved facility 5.7 47.3 27.1 66.1 42.5 18.4 38.9 24.5 78.5 47.8

Unimproved facility 4.1 0.1 6.1 0.0 2.1 0.0 17.8 0.1 0.0 3.6

No facility 57.9 51.6 38.2 21.4 38.1 80.8 30.5 74.2 19.8 45.0

Number of children 4,783 3,458 5,078 2,727 9,824 27,769 10,651 14,274

Disposal of child's feces

Sanitary disposal 66.8 63.1 76.5 65.1 67.3 15.3 59.9 18.9 45.1 36.9

Unsanitary disposal 33.2 36.9 23.5 34.9 32.7 84.7 40.1 81.1 54.9 63.1

Number of children 3,971 3,074 4,503 2,349 9,274 25,338 10,088 13,299

Cont’d..

11
Table 2: Cont’d

Household environment 

variables

Low mortality countries High mortality countries

Namibia Lesotho Zimbabwe Swaziland Average Niger Nigeria

Burkina 

Faso Mali Average

Type of flooring material

Finished 45.8 53.6 59.6 87.2 66.7 11.7 54.9 34.2 23.1 29.4

Rudimentary 0.5 0.1 0.2 0.1 0.2 0.0 1.0 0.0 0.0 0.2

Natural 53.7 46.4 40.2 12.7 33.1 88.3 44.1 65.8 76.9 70.4

Number of children 4,784 3,462 5,086 2,728 9,823 27,837 10,659 14,277

Type of cooking fuel

Non biomass fuel 32.3 17.9 26.8 24.9 25.4 0.3 1.2 0.9 0.1 0.5

Biomass fuel 67.7 82.1 73.2 75.1 74.6 99.7 98.8 99.1 99.9 99.5

Number of children 4,776 3,460 5,080 2,050 9,807 23,108 10,635 14,284

Use of mosquito net

Yes 15.5 NA 7.9 0.9 6.3 18.0 14.4 24.1 48.7 30.8

No 84.5 NA 92.1 99.1 93.7 82.0 85.6 75.9 51.3 69.2

Number of children 4,232 NA 4,762 2,487 9,568 26,712 10,318 13,701

Household environmental health hazard

Non potential 26.9 11.8 26.1 21.2 21.4 0.2 0.9 0.8 0.1 0.4

Low potential 20.9 37.2 28.5 48.9 36.9 15.3 46.0 28.5 50.9 38.3

High potential 52.2 51.0 45.4 29.9 41.7 84.5 53.1 70.7 49.0 61.3

Mean (of 5 indicators) 2.8 2.6 2.8 3.3 2.9 1.3 2.4 1.9 2.5 2.1

12
13

An examination of the sanitary facilities within the household reveals that the use of flush 

toilet facilities is very low in all the selected countries, with Lesotho, Niger, Mali, and Burkina 

Faso at less than 2%. Although in Zimbabwe and Namibia more than 25% of children live in 

households with a flush toilet, this figure is still lower than might be expected. Except for Mali 

and Swaziland, about five in ten households in all the surveyed countries use unimproved toilet 

facilities, or have no toilet facility. 

Because lack of availability of a sanitary facility can be a public health concern and can 

have adverse implications for child health, the proper disposal of feces is also crucial. A large 

proportion of households in the selected low-mortality countries dispose of children’s feces 

properly. Conversely, most of the households in high-mortality countries, except for Niger, 

dispose of children’s feces in an unsanitary manner. Several studies in sub-Saharan countries on 

childhood mortality have found that improper disposal of excreta was definitely related to high 

incidence of childhood morbidity. There is increased prevalence of diarrhea and cholera in such 

households, which could contribute to childhood mortality (Ayeni and Oduntan, 1980; Tankins, 

1981; Trussell and Hammerslough, 1983; Obungu, Kizito, and Bicego, 1984; Jinadu et al, 1991; 

Rutsein, 2000). 

It has been observed that the type of materials used for flooring is an indicator of the 

economic situation of households and a source of exposure to disease-causing agents (NPC, 

2004). This study therefore examined the main flooring materials in households of mothers who 

gave birth within the five years before the survey. The results show that, although there are slight 

variations in the type of flooring material among the selected low-mortality countries, on average 

about 67% live in households with finished flooring material such as cement, carpet, or rug. 

While very few children in low-mortality countries live in households with natural or 

rudimentary flooring, most households in Niger, Burkina Faso, and Mali use natural flooring 

material, which is common among rural dwellers. The natural flooring materials include earth 

and sand, which could have an adverse effect on the health of children under age five, especially 

those who are still crawling. 

The type of cooking fuel used in the household is an important variable, as many children 

are exposed to toxic pollutants from the use of unprocessed biomass fuel from wood, charcoal, 

straw, and dung. Unprocessed biomass fuels have a high level of toxic indoor air pollutants that 
14

have been linked to reduced birth weight, ARI, nutrition deficiency, and child mortality (Mishra 

and Retherford, 2007). Studies have shown that mothers and their young children are at high risk 

of exposure to the smoke emitted from burning of coal, firewood, and other sources of fuel 

because of women’s traditional role in the preparation of food and childcare practices while 

cooking (Rutstein, 2000). More than 65% of children in the selected countries live in households 

where their mothers cook with firewood, charcoal, or straw. 

Malaria-carrying mosquitoes are another health hazard, responsible for many deaths, and 

the groups most vulnerable are children under age five and pregnant women (NPC, 2004). The 

DHS asked respondents about the use of mosquito nets by household members in the previous 

night before the interview. Despite high awareness of malaria prevention using mosquito nets for 

children under age five, findings show that such use was low among all the selected countries. 

Use of mosquito nets for children under age five is more prevalent in high under-five mortality 

countries than in low under-five mortality countries, with the highest level (48.7%) in Mali, a 

high-mortality country, and the lowest level (0.9%) in Swaziland, a low-mortality country. 

Overall, the results from the study show that in low under-five mortality countries 27%, 

12%, 26%, and 21% of children in Namibia, Lesotho, Zimbabwe, and Swaziland, respectively, 

live in a household environment classified as having non- health hazard. Though these 

proportions are quite low, they are much higher than the proportions in the high under-five 

mortality countries studied, where negligible numbers live in households with non- health 

hazard—about 0.2% in Niger, 0.9% in Nigeria, 0.8% in Burkina Faso, and 0.1% in Mali. 

Moreover, except for children in Swaziland, more than four in ten children under age five live in 

households classified as having high health hazard. This is unacceptably high and raises a serious 

concern about public health in Africa, especially for the four high-mortality countries studied, 

where about 99% of the children are exposed to at least one health hazard in the household. 

These results indicate that low-mortality countries have a higher proportion of 

households with improved sources of drinking water, improved toilet facilities, sanitary disposal 

of children’s feces, finished flooring, and use of non-biomass fuel for cooking. Countries in the 

high-mortality group are more exposed to the risk of under-five deaths in the household. A 

substantial proportion of households in high-mortality countries have unimproved sources of 

drinking water, lack basic sanitary facilities, and use more biomass fuel for cooking. This is 
15

reflected in the overall score of household health hazards. In the selected countries with high 

childhood mortality, 64% of sampled children live in households with high health hazards, 

compared with 42% in countries with low childhood mortality. 

Household Environmental Health Hazards and Background Characteristics 

There are significant associations between household environmental health hazards and 

background characteristics such as maternal education, paternal education, and rural or urban 

residence, as well as household wealth. Further measures of association for categorical rank 

variables—Spearman rank correlations—also show the magnitude and direction of these 

relationships (Table 3). As expected, the level of parental education is closely related to the 

household environments in this study; in all the selected countries, more than 90% of children 

whose mothers have tertiary education live in households with low or non- health hazards. In all 

the selected countries, the higher the parent's educational level, the lower the likelihood of a 

health hazardous household environment for children under age five (p<0.001). It is of note that, 

among the high under-five mortality countries, while all the children of mothers with tertiary 

education in Niger, Burkina Faso, and Mali live in a presumably safe environment, 8% of their 

counterparts in Nigeria live in households with high health hazards. 

This study also buttresses the association found in various publications on urbanization 

and household environment; it is evident in the literature that urban-rural residence influences 

good sanitation and housing environments (Woldemicael, 2000; Balk et al, 2004; Macassa et al, 

2004). The significant positive relationship observed in this study among all the selected 

countries implies that those living in urban areas are much less likely to have health hazards in 

their household environment. However, the pattern of household environmental health hazards 

differs among the low and high under-five mortality countries for both rural and urban areas. 

More than 9 in 10 children in urban Swaziland, Lesotho, and Zimbabwe live in households with 

non- or low health hazards. Children under age five living in rural areas in Africa are likely to be 

more exposed to household health hazards because of lack of basic infrastructure and amenities. 

The highest proportion is found in rural Niger, a high-mortality country, while the lowest 

proportion is found in rural Swaziland, a relatively low-mortality country. 
Table 3: Background characteristics and household environmental health hazards in low and high under-five mortality countries in SSA

Characteristics

Low mortality countries

Namibia Lesotho Zimbabwe Swaziland Overall

N/LPHH HPHH N/LPHH HPHH N/LPHH HPHH N/LPHH HPHH N/LPHH HPHH

Maternal highest education

None 22.7 77.3 18.0 82.0 21.3 78.7 52.7 47.3 29.2 70.8

Primary 28.8 71.2 40.9 59.1 32.1 67.9 60.5 39.5 38.6 61.4

Secondary 58.7 41.3 67.2 32.8 69.9 30.1 76.8 23.2 67.0 33.0

Higher 91.7 8.3 96.6 3.4 96.6 3.4 96.9 3.1 94.5 5.0

Spearman rank correlation 0.345** 0.298** 0.387** 0.250** 0.331**

Paternal highest education

None 24.7 75.3 21.4 78.6 20.3 79.7 47.9 52.1 26.0 74.0

Primary 32.9 67.1 49.1 50.9 29.2 70.8 56.4 43.6 41.2 58.8

Secondary 62.1 37.9 70.0 30.0 64.0 36.0 78.7 21.3 66.2 33.8

Higher 86.0 14.0 94.3 5.7 97.6 2.4 97.2 2.8 93.5 6.5

Spearman rank correlation 0.330** 0.353** 0.371** 0.327** 0.353**

Place of residence

Rural 21.9 78.1 41.8 58.2 36.0 64.0 62.1 37.9 38.8 61.2

Urban 85.1 14.9 92.7 7.3 100.0 0.0 98.0 2.0 92.5 7.5

Spearman rank correlation 0.528** 0.404** 0.569** 0.356** 0.485**

Wealth Index

Poor 1.8 98.2 8.6 91.4 11.9 88.1 43.7 56.3 13.5 86.5

Middle 49.6 50.4 60.7 39.3 73.0 27.0 79.1 20.9 63.6 36.4

Rich 98.9 1.1 92.6 7.4 98.8 1.2 94.3 5.7 96.7 3.3

Spearman rank correlation 0.837** 0.768** 0.793** 0.515** 0.752**

Cont’d..

16
Table 3: Cont’d

Characteristics

High mortality countries

Niger Nigeria Burkina Faso Mali Overall

N/LPHH HPHH N/LPHH HPHH N/LPHH HPHH N/LPHH HPHH N/LPHH HPHH

Maternal highest education

None 11.3 88.7 29.9 70.1 24.8 75.1 24.8 75.2 29.9 70.1

Primary 34.8 65.2 47.0 53.0 52.1 47.9 52.1 47.9 49.5 50.5

Secondary 77.2 22.8 69.2 30.8 87.6 12.4 87.6 12.4 71.7 28.3

Higher 100.0 0.0 91.8 8.2 100.0 0.0 100.0 0.0 92.2 7.8

Spearman rank correlation 0.396** 0.341** 0.290** 0.204** 0.329**

Paternal highest education

None 11.0 89.0 27.1 72.9 23.8 76.2 45.7 54.3 28.3 71.7

Primary 28.5 71.5 45.4 54.6 50.6 49.4 58.5 41.5 46.3 53.7

Secondary 57.6 42.4 62.8 37.2 81.7 18.3 83.1 16.9 65.3 34.7

Higher 91.0 9.0 77.3 22.7 98.8 1.2 92.8 7.2 79.1 20.9

Spearman rank correlation 0.367** 0.367** 0.338** 0.281** 0.340**

Place of residence

Rural 4.6 95.4 33.2 66.8 20.4 79.6 39.2 60.8 27.0 73.0

Urban 78.0 22.0 79.1 20.9 91.5 8.5 83.1 16.9 81.1 18.9

Spearman rank correlation 0.762** 0.406** 0.537** 0.396** 0.471**

Wealth Index

Poor 0.0 100.0 15.1 84.9 0.0 100.0 31.2 68.8 13.9 86.1

Middle 0.0 100.0 52.5 47.5 17.6 82.4 40.3 59.7 34.6 65.4

Rich 39.8 60.2 86.0 14.0 75.7 24.3 78.5 21.5 74.7 25.3

Spearman rank correlation 0.570** 0.628** 0.692** 0.416** 0.544**

** p<0.001; * p<0.05; HEHH: Household environmental health hazards; 

N/LPHH: Non/Low Potential health hazards; HPHH: High Potential health hazards

17
18

The household wealth index, categorized into highest, middle, and lowest, is another 

background characteristic examined in this study. It has been established in demographic studies 

that the wealth index is a good indicator of the influence of social class on the health of mother 

and child (NPC, 2004). The higher the wealth index, the greater is the likelihood of a good 

household health environment. Therefore, children from lower social classes may be more likely 

to be subject to ill health due to household environmental health hazards. For this study, there is 

a significant strong inverse relationship between being in households in the highest wealth index 

quintile and living in a poor environment, for all the selected countries. In Lesotho, Namibia, 

Zimbabwe, Niger, Nigeria, and Burkina Faso, over 80% of children living in households in the 

lowest wealth index quintile are exposed to high household environmental health hazards. 

However, in Swaziland 44% of children in poor households are in a non- or low health hazard 

environment. 

In addition, within the high wealth index category, there are substantial differences 

among the selected countries in the percentages with household environmental health hazards. 

The percentages of the high wealth index group living in a high health hazard environment are 

60%, 24%, 22%, and 14% in Niger, Burkina Faso, Mali, and Nigeria, respectively. Conversely, 

in this same wealth index group only 1% in Namibia and Zimbabwe, 6% in Swaziland, and 7% 

in Lesotho are in a high health hazard environment. Among the low-mortality countries, Lesotho 

has the largest percentage of the high wealth index group living in a more hazardous 

environment, while among the countries with high under-five mortality, the largest percentage is 

in Niger. 

Household Environmental Health Hazards and Childhood Morbidity 

Figure 1 shows the patterns of childhood morbidity in the selected countries. Three major 

patterns of childhood morbidity that were experienced in the two weeks preceding the survey 

were examined: diarrhea, fever, and ARI. Dehydration from diarrhea has been identified as one 

of the causes of death among children under age five. Among the analytical sample, data on 

childhood diarrhea in the last two weeks preceding the survey show that in Burkina Faso and 

Niger children under age five have the highest incidence of diarrhea. Two low-mortality 

countries, Swaziland and Lesotho, however, have a higher prevalence of childhood diarrhea than 
19

Nigeria, in the high-mortality group. Further examination of the household risk factor on 

childhood diarrhea using logistic regression (Table 4) reveals that the source of drinking water 

and the type of cooking fuel have a significant effect on diarrhea for the two mortality groups. 

However, type of toilet facility and flooring material are also significant household environment 

risk factors that can affect diarrhea in the high-mortality countries. 

Figure1: Prevalence of diarrhea, fever, and ARI in the past 2 weeks among children under age five 

in sub-Saharan Africa 

17%

13%

11%

7%

12%

8%

5%

4%

26%

28%

8%

17%

27%

37%

18%

16%

14%

14%

12%

12%

21%

21%

13%

10%

Lesotho

Swaziland

Zimbabwe

Namibia

Niger

Burkina Faso

Mali 

Nigeria

Diarrhea Fever ARI
20

Table 4: Risk of childhood morbidity by household environmental factors in low and high underfive mortality countries in SSA

Diarrhea Fever ARI

Low U5 

mortality 

group

High U5 

mortality 

group

Low U5 

mortality 

group

High U5 

mortality 

group

Low U5 

mortality 

group

High U5 

mortality 

group

Source of drinking water -

Improved source 0.815* 0.946* 0.886* 1.084* 0.847* 1.120*

Time to water source -

On premises/less than 30 minutes 0.971 0.968 0.838* 0.916** 0.773** 0.771**

Toilet facility -

Improved toilet facility 0.965 0.889** 1.066 0.800** 1.061 0.750**

Flooring material -

Finished flooring 1.038 0.598** 1.206* 0.824** 0.951 0.818**

Type of cooking fuel -

Non-biomass fuel 0.798* 0.622* 0.780** 1.124 0.621** 0.721

Disposal of child's feces -

Sanitary disposal 0.966 1.040 0.780** 0.839** 0.870* 0.836**

** p<0.001; * p<0.05 

It is evident in this study that if the drinking water of a household in the low under-five 

mortality group is from an improved source, the risk of diarrhea significantly decreases by 11%, 

while for the high under-five mortality group the risk decreases by 6%. Although there is a 

decrease in childhood diarrhea if the household drinking water is from an improved source, the 

expected high effect of source of drinking water on childhood diarrhea is likely to be distorted by 

other factors, such as fetching, storage, and treatment of the drinking water. Also, the high 

incidence of childhood diarrhea in Lesotho might be a result of other causes, since the country 

has the highest proportion of those with an improved source of drinking water. 

In a household where the cooking fuel is non-biomass, the risk of childhood diarrhea 

significantly decreases by 20% for the low-mortality group, and 38% for the high-mortality 

group, compared with households that use biomass fuel such as charcoal, firewood, and straw. 

Therefore, for all the selected countries a change in the household cooking fuel to non-biomass, 

such as electricity, gas, and kerosene, can reduce the risk of childhood diarrhea, especially 

among the high under-five mortality group. 

Children under age five in the high-mortality countries that live in households with an 

unimproved toilet, such as open pit, bucket, hanging toilet, pit latrine without a slab, or with no 
21

facility are significantly more likely to have episodes of diarrhea than others with an improved 

toilet facility. An unimproved toilet facility that is not constantly clean is a route for infection 

and germs that could affect young children. Likewise, children under age five in the highmortality countries living in households with natural and rudimentary flooring have higher risk 

of diarrhea than those in households with finished flooring, with particular consequences for the 

health of toddlers, who are likely to crawl and pick up dirty things on the floor. 

World Health Statistics 2009 (WHO, 2009) estimates that fever is a common childhood 

illness in developing countries, especially in sub-Saharan Africa, where about 15 of every 1,000 

children born die from malaria before age five. Consistent with the WHO report, this study found 

that, in seven of the eight selected countries, fever is the most common childhood illness within 

the two weeks preceding the DHS survey (Figure 1). The exception is Zimbabwe, where the 

prevalence of fever is only 8% in the two weeks preceding the survey. However, in Lesotho and 

Swaziland prevalence of fever is relatively high compared with the other two countries in the 

low-mortality group. 

In this study the prevalence of fever is highest in Burkina Faso. Burkina Faso also has the 

highest prevalence of childhood diarrhea. This is consistent with the assumption that a child that 

has diarrhea might likely have fever, because of lower immunity from dehydration. Another 

factor that might be responsible for this high prevalence is the overall low usage of mosquito 

nets, in spite of malaria awareness and prevention campaigns. Although all these household risk 

factors affect the incidence of fever, the level of exposure varies from one country to another. 

Acute respiratory infection, characterized by coughing and short rapid breaths, is also one 

of the major causes of childhood mortality in developing countries. Figure 1 shows that the 

prevalence of ARI is higher in the low-mortality countries, as measured within the two weeks 

preceding the survey. For example, 17% of children in Lesotho have symptoms of ARI, the 

highest prevalence among countries in this study, while Nigeria has the lowest prevalence of 

ARI, at 4%. Further analysis in Table 4 shows a similar pattern for fever and diarrhea on 

household risk factors that can predispose a child to ARI. 
22

Household Environmental Health Hazards and Childhood Mortality 

Table 5 shows the risks of childhood mortality according to household environmental 

health hazards. The findings reveal that in the group of countries with low under-five mortality, 

with the exception of Swaziland, there is increased risk of under-five mortality by the level of 

household environmental health hazards. Although the differences are not significant, the finding 

implies that, keeping all other factors constant, at the end of five years in low-mortality countries 

92% of children living in non- health hazard environments will survive, while 91% of those 

living in high health hazard environment will survive. 

Table 5: Risk of under-five mortality based on household environmental health hazard 

Country Non HEHH Low HEHH High HEHH

Low childhood mortality 92 91 91

Namibia 95 92 92

Lesotho 90 88 88

Zimbabwe 93 92 92

Swaziland 89 89 89

High childhood mortality ** 96 87 84

Niger** 95 90 85

Nigeria** 97 87 84

Burkina Faso** 95 87 84

Mali* 93 85 83

** p<0.001; * p<0.05; HEHH: Household environmental health hazards

Whereas, overall, the high-mortality group shows a 96% chance of children surviving to 

age five in non- health hazard household environments, children in high health hazard 

environments have an 84% survival chance. It is clear from these findings that children under 

age five in non- health hazard environments among the high-mortality group have more chance 

of survival than their counterparts in the low-mortality group of countries. Within a country, 

differences in household environmental health hazards and survival of children under age five 

are more distinct in the high-mortality group than the low-mortality group. In Mali, for instance, 

there is a 93%, 85%, and 83% chance of survival for non-, low, and high health hazard 

environments, respectively. 
23

Table 6 presents further analysis using the Cox hazard regression model. The regression 

analysis was based on the independent effect of the household environment on under-five 

mortality and an adjusted household score, after controlling for the background characteristics 

(education, residence, and wealth index) that could influence the level of exposure of children to 

household environmental health hazards, such that the actual household health hazards index is 

an intermediate variable—that is, household environmental health hazards are not independent of 

some background variables. The adjusted household environmental score as independent 

variable would reveal the effect on childhood mortality of the background variables, working 

through the household environmental health hazards. 

Table 6: Relative hazards of under-five mortality in selected SSA countries 

Country HEHH Adjusted HEHH

Low childhood mortality 0.974 0.956

High childhood mortality 0.913* 0.799**

Namibia 0.941 0.922

Lesotho 1.015 1.034

Zimbabwe 0.944 0.909

Swaziland 1.002 1.056

Niger 0.919** 0.866**

Nigeria 0.892** 0.776**

Burkina Faso 0.903** 0.836**

Mali 0.905** 0.787**

** p<0.001; * p<0.05; HEHH: Household environmental health hazards;

Adjusted HEHH: Household environment after controlling for education, wealth and residence

The result from the multivariate analysis shows that there is a significant effect of 

household environmental health hazards on under-five mortality for high childhood mortality 

countries. A unit increase in the household environment score will significantly decrease the 

relative hazard of under-five deaths by 9% (relative hazard-0.91), while a unit increase in the 

adjusted household environment score will significantly decrease the relative hazard of underfive deaths by 20% (relative hazard-0.80)3

. There is a similar pattern in all four of the selected 

 

3

 Hazard rate percentage calculated by {[(E(b) – 1.0)/1.0]*100} 
24

high-mortality countries. The independent effect of household environment in this study will 

reduce the relative hazards of under-five deaths in Burkina Faso, Niger, Nigeria, and Mali by 

10%, 8%, 11% and 10% respectively. However, when maternal education, residence, and wealth 

index is controlled on the household environment score, the relative hazards of death 

significantly reduce to 16%, 13%, 22%, and 16% in Burkina Faso, Niger, Nigeria, and Mali, 

respectively. 
25

CONCLUSIONS 

Disparities exist in the household environment of children in the selected sub-Saharan 

African countries; the high under-five mortality groups are at a relative disadvantage on basic 

household environmental variables that affect hygiene. There are also significant relationships 

between household environment and child survival in sub-Saharan Africa. Some of the 

differences in childhood morbidity and mortality in low and high under-five mortality countries 

can be explained by levels of household environmental health hazards. Socioeconomic status of 

mothers is salient in the reduction of childhood morbidity and mortality from health hazards 

within the household. 

In order to meet Millennium Development Goal 4—to reduce under-five mortality by 

two-thirds between 1990 and 2015—prompt attention should be given to various factors 

affecting the equal distribution of resources and facilities to every part of sub-Saharan Africa, 

especially the high-mortality countries. Policy should be redirected to programs that encourage 

household hygiene and sanitation. Interventions on water accessibility and basic sanitation 

should be jointly provided by different sectors, especially for countries where under-five 

mortality rates are high. Government, non-governmental organizations, and the private sector 

should seek to invest in programs that promote a healthy and hygienic household environment 

and increase access to clean water and good sanitation as part of community development efforts 

in sub-Saharan Africa. Women should also have more access to education and information on 

best childcare practices in the household environment, irrespective of their place of residence. 
26

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