solar disinfection of drinking water protects against cholera in children under 6 years of age - empty plastic drinking bottles
Background and purpose we have previously reported a reduction in the risk of diarrhea in children using solar to disinfect drinking water.
A cholera epidemic occurred in an area of Kenya, where a control trial for solar disinfection and diarrhea diseases in children under 6 years of age was recently concluded, an opportunity is provided to check the protection of cholera by solar disinfection.
Methods in the initial trial, all children under the age of 6 in the Maasai community were randomly assigned to their families: in the solar disinfection Group, the children put the sterilized water in a clear plastic bottle on the roof, while the control group put the water indoors.
We re-examined all the families involved in the initial trial.
Results there were 131 households in the test area, of which 67 were randomly assigned to solar disinfection (
Another 19 households were relocated due to severe drought).
There was no significant difference in the risk of cholera in adults or older children in families who were randomized to solar disinfection;
However, of the 155 children under the age of 6, only 3 were drinking solar disinfectant water, compared with 20 in the 144 controls.
Conclusion The results confirm the effectiveness of solar disinfection in reducing the risk of water-borne diseases in children.
Consumption point solar disinfection can be done with very few resources that are readily available and may be an important first-line response to cholera outbreaks.
Its potential in the fight against cholera deserves further study.
We have described these methods in detail before.
12 all families of children under the age of 6 living within approximately 400 square kilometres of the Kajiado district, extending south from Taporu to Lake Magadi, are randomly divided into solar disinfection or control
All families have enough 1.
5 liters of clear plastic bottles to ensure adequate drinking water supply for all children under 5 years of age.
Under solar disinfection conditions, the mother is instructed to maintain the supply of drinking water for children under 5 years of age in plastic bottles on the roof;
In the control family, the mother is instructed to keep the water indoors with plastic bottles.
All children under the age of 5 are instructed to drink only from these water supplies.
Another family was randomly grouped.
Maasai health workers or one of us visited all the families involved in the study within six weeks of the outbreak (MEM)
He speaks fluent Marseille and has been working in the region for the past 20 years.
Because there are few medical facilities in the study group's families, it is impossible to conduct a bacterial investigation of any case.
Therefore, it is necessary to establish an oral diagnosis on the basis of translating the clinical features of cholera into Maasai.
Three mothers and grandmothers were interviewed when necessary to determine whether someone in the family was seriously ill during the outbreak.
All interviews were completed within eight weeks of the outbreak.
If anyone has a sudden diarrhea disease, they or their mother (
In the case of children)
Someone asked him what he was sick.
Detailed questions were raised regarding all cases of massive watery diarrhea.
Cholera is diagnosed when the case meets these criteria:1)
Someone described it with the specific Maasai words of cholera used by the tribes of the people interviewed. (2)
It includes three typical features of cholera confirmed by Marseille: enkalokani-
A lot of dehydrated diarrhea, very water, there is a typical "cholera" smell, the taste is a bit bitter (aishamisham)
, And the texture of the milk that has recently changed sour, or the texture of the slurry made of och color nepuk --
Urine volume decreased significantly, usually accompanied by changes in skin tone, depressed eyes, wrinkled skin
The literal meaning is "calf muscles from the inside to the outside ";
Calf muscle cramps associated with diarrhea.
The disease must meet all four criteria in order to be rated as cholera.
The Maasai terminology used to describe the disease was recorded.
Cholera is diagnosed only when a child under 3 years of age has a typical medical history and at least one clear case in the child's family.
The analysis was carried out on the basis of intended treatment and, according to the initial randomized grouping, the family was classified as using solar disinfection or control.
While all householders claim to continue to deal with early childhood drinking water as directed, it is not possible to conduct an objective assessment of compliance, as no field staff visited these families during the outbreak.
Therefore, the protection effect proposed here must be considered as a minimum estimate.
However, due to the free-
This can be seen as evidence of the public health utility of solar disinfection in reducing the risk of cholera.
Because the use of solar disinfection was carried out randomly by the family, the robust variance estimates implemented in the svy program of Stata were used to adjust the variance and confidence intervals.
Each family enters as a cluster (
Primary sampling unit).
In addition, since there is a large difference in the risk of cholera among the seven sites involved in the study, the analysis is stratified by location.
Logistic regression with variance adjustment of clustering design (
Children randomly assigned by family)
Implemented in Stata's program svylogistic to express the relationship between the risk of cholera and the use of solar disinfection by children under 6 years of age.
4 As a result, in September 1997, we recorded data from 131 families, including 299 children who participated in the study of diarrhea diseases, so they were under the age of 6.
Another 19 families, including 50 children who participated in the diarrhea disease trial, have moved out of the area due to the drought that has affected the area in the past three years.
Thirty-one families have had cholera in line with the above definition.
Of the 24 families, two adults (
People over 15 years old)
Age is big of childrenaged 6–15)
Of the six families, only older children were affected and only adults were affected in one family.
Two elderly people aged 6 to 15 and two children died.
At the time of the outbreak of cholera, sixty-seven out of 131 households used solar energy to disinfect.
Cholera in children aged 6-15 years (23. 9%)
Of these families, with 14 (21. 9%)
Control households (Relative risk 1. 09, 95% CI 0. 58 to 2. 05).
Adult cholera in 14 years (20. 9%)
In households that have been disinfected using solar energy for 11 years (17. 2%)
Control households (Relative risk 1. 2, 95% CI 0. 59 to 2. 5).
There were 155 children under the age of 6 in households using solar disinfection and 144 children under the age of 6 in control families.
There were 3 cases of cholera in children using solar disinfection water, and 20 cases in control children, with a ratio of 0. 12 (95% CI 0. 02 to 0. 65, pu2009=u20090. 014).
Discussion about the cholera outbreak that occurred shortly after the end of the formal solar disinfection test provides a unique opportunity to study the effects of solar disinfection, which is neither practical nor practical, it is also not ethical ethics a prospective controlled trial because once an outbreak occurs, investigators are obliged to start preventive measures.
In fact, only young children in each household drink solar disinfection water, which also allows for stricter testing of the effect, because this should not occur in older children or adults.
Therefore, under the conditions of studying the usual occurrence of cholera, these data are as close as possible to the randomized controlled design.
Research data were collected through oral reports, not confirmed by bacterial surveys, which is the only realistic way to collect most of the cholera data
In sub-Saharan Africa, even if patients go to regional hospitals, laboratory facilities for validation diagnosis may not be available.
This is the case with the sites involved in this study where there is no facility in the feces to identify cholera.
However, it is worth noting that the cases are continuing, and on March 1999, health officials used the same case definition used here to investigate 43 cases found by health workers in Marseille, of these, 42 cases were identified as cholera.
In fact, the medical terminology of Masai is rich and precise in the classification of diarrhea diseases.
They are familiar with the outbreak of cholera in the region and have accurate vocabulary to describe its main features in their language.
Despite the diagnosis and treatment of severe cholera (cholera gravis)
As we all know, the problem of public health management becomes more complicated because infected patients rarely develop into serious forms of disease, and people over the age of 5 will have no symptoms.
Therefore, effective public health measures must be taken at the community level and emphasis must be placed on the use of disinfection as an important factor in Control and Prevention.
2 Solar disinfection provides the possibility of using low-cost or zero-cost interventions that communities can quickly implement as the first line of defense without waiting for help from the outside world, even in the poorest areas, empty plastic bottles become ubiquitous.
In addition, even in highly turbid water, bacteria can be significantly inactivated under relatively low optical radiation.
6 Solar disinfection may provide a way to reduce the risk of infection while finding more durable and effective solutions to water quality problems.
However, further work is needed to clarify the role of solar disinfection in the inactivation of the C-group cholera virus.
McKenzie and his colleagues reported that in high altitude areas (2850 metres)
Sunlight has a considerable sterilization effect, which is much smaller at 500.
7 There have also been concerns recently about the development of a "rugose" cholera virus that may be resistant to chlorine disinfection.
Although the results presented here do not provide exact evidence, it is no doubt that solar disinfection should be evaluated as a rapid response to cholera outbreaks in terms of reducing the risk of cholera, once anti-chlorine cholera becomes a public health problem,
Finally, our study highlights the potential of using detailed knowledge of national medical concepts to carry out field work in disease investigations.
Traditional culture is not a medical ignorance, but a complex classification of diseases that can be used to establish reliable oral diagnosis and screening procedures.
This traditional medical knowledge is an underutilized resource in health promotion and disease investigation.
In addition, the close combination of disease investigations with the traditional medical reference framework can pave the way for credibility of the results and for the community to take preventive measures.
The study was funded by the Royal College of Surgeons of Ireland.
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