DIARRHOEA ACCOUNTS FOR HIGH LEVELS OF MORALITY IN YOUNG CHILDREN IN DEVELOPING COUNTRIES IN NIGERIA
Chapter 1
Introduction
1.1 Background
Diarrhoea disease accounted for 4.6 Billion cases and 2.16 Million deaths worldwide in the year 2004 of which more than 50% were from low income countries and most of the cases were children under five years. In the year 2004, one of the two leading cause of burden of disease was diarrhoea, also diarrhoea accounted for 32,203,037 DALYS in Africa and the majority of which are children under the age of Five years61.Also in meta analysis of 60 studies of diarrhoea morbidity and mortality in between1990 to 2000 diarrhoea accounted for 21% of all deaths of children under five years annually and mostly from developing countries 65
Africa and South East Asia countries accounted for 75% of all deaths; Tanzania according to Boschi-Pinto 4 was among the 15 countries that accounted for 75% of all deaths.
World health organization estimates that 88% of all diarrhoea diseases are due to unsafe water supply, inadequate sanitation and poor hygiene practices. For the year 2002 alone an estimated 1.1billion people lacked access to improved water sources 59, 8
It was found that infectious agents associated with diarrhoea are transmitted mainly through faecal oral routes, which are bacteria, viruses and protozoa excreted in the human faeces causes’ diarrhoea 5. Also most of the pathogens that cause diarrhoea are transmitted through ingestion of contaminated water38. Experts in water quality and safety have developed many interventions for water treatment, these include Physical removal of pathogens (Filtration, adsorption and Let it stand and settle),Chemical treatment (assisted Let it stand and settle, chemical disinfection and ion exchange), heat and ultra violet UV radiation 63.These efforts of improving the quality of water also included steps of maintaining residual disinfection and improved storage thus the United Nations Mission of reducing to half of the 1.5billion people without access to safe water 58
Meta analysis of 67 studies found that improved water quality may results into median reduction of 16% of diarrhoea morbidity 32
Another finding indicated that even the safe water can become contaminated during collection, transport and drawing in the home 17.The low cost intervention of improving and preserving household water quality should be adopted 64
WHO has formulated and sponsoring an international Network for the promotion of safe household water treatment and safe storage.
A brief analysis of 21 controlled field trials over the last 20 years dealing specifically with interventions designed to enhance microbiological quality of drinking water at household level showed a median reduction in endemic diarrhoea diseases by 42% compared with the control group 63
Normally Children with poor nutritional status and overall health, as well as those exposed to poor environmental conditions including unsafe drinking water, are more susceptible to severe diarrhoea and dehydration than healthy children. Children are also at greater risk than adults of life-threatening dehydration since water constitutes a greater proportion of children’s bodyweight. Young children use more water over the course of a day given their higher metabolic rates, and their kidneys are less able to conserve water as adults 65
Interventions to improve water quality at the source, along with treatment of household water and safe storage systems, have been shown to reduce diarrhoea incidence by as much as 47 per cent 61
Millennium development Goals 7, Target 10, calls for reducing by half the proportion of people without sustainable access to safe drinking water by 2015. Reaching this target implies that we need to tackle both the quantity (access) and quality (safety) dimensions to drinking water provision.
1.1.1 Household Point of use water treatment technologies
According to WHO there are about 37 different technologies for use at household level for treatment of drinking water in the home 14 Few have been assessed for microbial and health impact performance. In Tanzania the following are common in different places of Country.
1.1.2 Chlorination
This is the most widely-practised means of treating water at the community level; apart from boiling, it is also the method used most broadly in the home. The source of chlorine can be sodium hypochlorite, chlorinated lime, or high test hypochlorites (chlorine tablets) which are usually available and affordable. The sodium hypochlorite solution is packaged in a bottle with directions for users to add one full bottle cap of the solution to clear water (or two caps to turbid water) in a standard-sized storage container; agitate; and wait for 30 minutes before drinking. Chlorine must be added in sufficient quantities to destroy all pathogens but not so high that taste is adversely affected. At doses of a few mg/l and contact time of about 30minutes, free chlorine inactivates more than 99.99% of enteric pathogens, the notable exceptions being Cryptosporidium and Mycobacterium species. Its impact in reducing diarrhoeal diseases has been documented 1
1.1.3 Filtration
Household filters potentially present certain advantages over other technologies. They operate under a variety of conditions (temperature, pH, turbidity), introduce no chemicals into the water that may affect use due to objections about taste and odour, are easy to use, and improve the water aesthetically, thus potentially encouraging routine use without extensive intervention to promote behaviour change. Higher quality ceramic filters treated with bacteriostatic silver have been shown effective in the lab at reducing waterborne protozoa by more than 99.9% and bacteria by more than 99.9%, and their potential usefulness as a public health intervention has been shown in development and emergency
settings 22,23
The improving quality of locally-fabricated silver coated ceramics is particularly promising as a sustainable and low-cost alternative 3Slow-sand filters remove suspended solids and microbes by means of a slime layer (schmutzdecke) that develops within the top few centimetres of sand are capable of removing 99% of enteric pathogens if properly constructed, operated and maintained. Bio-sand filter is a simpler but more advanced version designed specifically for intermittent use and is more suitable for household applications. It has been tested both in the laboratory and the field 13, 16
1.1.4 Combination Flocculation and Disinfection (Aqua tabs)
The most challenge for household-based treatment is how to treat high turbid water, solids normally use up free chlorine and other chemical disinfectants. Turbidity can be managed by simple Let it stand and settle and pre-treatment. The use of alum can be effective and low-cost option for assisted Let it stand and settle but again disinfection is required such forms of assisted Let it stand and settle have been shown to reduce the levels of certain microbial pathogens, especially protozoa which may otherwise present a challenge to chemical disinfectants. Certain manufacturers have combined flocculation and timereleased disinfection in a single product that is sold in sachets for household use. One such product has been shown to reduce waterborne cysts by more than 99.9%, viruses by more than 99.9% and bacteria by more than 99.99% 15
1.1.5 Boiling
Boiling or heat treatment of water with fuel is effective against the full range of microbial pathogens and can be employed regardless of the turbidity or dissolved constituents of water. WHO recommend bringing water to a rolling boil for 1minute; this is mainly intended as a visual indication that a high temperature has been achieved; even heating to pasteurization temperatures (60º C) for a few minutes will kill or deactivate most pathogens. However, the cost and time used in procuring fuel, the potential aggravation of indoor air quality and associated respiratory infections pose a threat to public health.
1.1.6 Straining in cloth
Pouring turbid (cloudy) water through a piece of fine, clean cotton cloth will often remove a certain amount of the Suspended solids contained in the water. If the cloth is dirty, additional pollutants may be introduced! Purpose-made monofilament filter cloths can be used in areas where guinea worm disease (dracunculiasis) is endemic. Such cloths are effective in straining out the copepods in the water. These tiny water creatures act as intermediate hosts for the larvae which transmit the disease. Some guinea-worm eradication projects supply a large-diameter drinking straw with a filter mesh on one end so that copepods are strained out when water is sucked up the straw.
1.1.7 Storage and settlement
Storing water for just one day can result in the die-off of more than 50per cent of most Bacteria; conditions in storage vessels are usually not conducive to their survival! Longer periods of storage will lead to further reduction.
The cercariae, which are an intermediate host in the life cycle of schistosomiasis, can only live for 48 hours after leaving a snail if they do not reach a human or animal host. So storing water for more than two days effectively prevents the transmission of this disease
1.2 Statement of the problem
Diarrhoea was defined as having loose or watery stools at least three times per day, or more frequently than normal for an individual. Though most episodes of childhood diarrhoea are mild, acute cases can lead to significant fluid loss and dehydration, which may result in death or other severe consequences if fluids are not replaced at the first sign of diarrhoea.
Between 2004 and 2009 the diarrhoeal disease in Tanzania affected about 2.5Million children under five years and caused 3191 deaths with Case Fatality Rate (CFR=0.12%), which is an average of 430,314 cases and 532 deaths per year and the period prevalence of 588/10,000 population of under five years. In Tanzania, a child gets about 5 episodes of diarrhoea per year and the most frequently affected regions in the country are Shinyanga, Mara, Rukwa, Dodoma, Mbeya, Pwani and Kigoma 66
Diarrhoea was the fourth contributor of Outpatient visit and the fifth cause of Mortality among children under the age of five years in the year 2009 in Tanzania. 67 Mkuranga was among the top ten districts in Tanzania leading for diarrhoea among under five children despite improvement in water, hygiene and sanitation by AMREF since 2001
In Mkuranga diarrhoea among children under the age of five years was among the top ten causes of outpatient and inpatient attendance with the Outpatient prevalence of 12% 68
Children with poor nutritional status and overall health, as well as those exposed to unsafe drinking water are more susceptible to severe diarrhoea and dehydration than healthy children. Children are at greater risk than adults of life-threatening dehydration since water constitutes a greater proportion of children’s bodyweight
Young children use more water over the course of a day given their higher metabolic rates, and their kidneys are less able to conserve water as adults 65
Most pathogens that cause diarrhoea have similar mode of transmission – from the stool of one person to the mouth of another. This is known as faecal-oral transmission.
Interventions to improve water quality at the source, treatment of household water and safe storage systems, have been shown to reduce diarrhoea incidence by as much as 47 per cent.
Out of Tanzanian total population of 34.5 million people, access to safe drinking water among rural and urban populations are 42% and 73% respectively this is in accordance to Population and Housing Census of 2002. In that case a large population relies on water from ponds, rivers and other unsafe sources of which there rarely treated or disinfected.
Poor health associated with consumption of untreated drinking water at household level is one of the most significant concerns in Tanzania and other developing countries. Water, sanitation and hygiene related diseases claim many of the childhood illness in Tanzania.
The Tanzania National strategy for growth and reduction of poverty has indicated that the proportion of Urban and rural household using water from unprotected sources are 53% and 47% respectively and that water is rarely treated or disinfected.
In Mkuranga district more than 68% of the households depend on water from shallow wells which are not treated regularly by authorities due to constrain of budget 68
Millennium Development Goals (MDG) target 7 call for reduction by half the proportional of people without sustainable access to safe drinking water by 2015.Reaching this target imply tackling both quantity(access) and quality (safety) dimensions. Household interventions especially household water treatment and safe storage can make immediate contribution to the safety component of this target and would significantly contribute to
MDG.
Household water treatment also known as point of use water treatment (POU) has been shown to be an effective means of reducing diarrhoea and other diseases associated with unsafe drinking water 14
In 2005 systematic review, researchers concluded that diarrhoea can be reduced by 39% through household water treatment and safe storage (HWTS) 11
Despite the gain in health due to household water treatment indicated in various research works still there is low coverage of household water treatment in Tanzania ranging from 30% in rural areas to 52, 5% in urban areas 69
Numerous studies on drinking water treatment and diarrhoea have been undertaken outside Tanzania have shown relationship between general diarrhoea and household water treatment. Data are scarce on factors associated with diarrhoea among Children under the age of five years in relation to household water treatment and Safe storage. It is therefore necessary to consider the role of household water treatment and safe storage on diarrhoea among children under the age of five years. This study attempted to fill the gaps created by earlier studies in view of providing a more appropriate framework on the relationship between household water treatment and safe storage and diarrhoea among children under the age of five. These data generated by this study will help to design important intervention on diarrhoea in the community by promoting the use of existing technologies to treat drinking water the study have also documented the microbial contamination of drinking water.
1.3 Rationale of the study
The significance of this study was to understand the relationship between under five diarrhoea and Household water treatment and safe storage. Also to generate information of what people do to make their drinking water safe by understanding different local water treatment options and to what extent they reduce the bacterial load in drinking water. Therefore with this information the government and communities can build upon popular and effective water treatment technologies and storage options which are effective and acceptable.
1.4 Research questions
1. Why people do not treat their drinking water as the measure of reducing diarrhoea in the community.
2. What is the association between reported diarrhoea and bacterial contamination of drinking water?
3. What is the relationship between reported diarrhoea and reported water treatment?
4. What are other risk factors which are associated with microbial contamination of drinking water?
