Epidemiology provides a scientific basis for clinical and health practice., epidemiology can be used to show how we define, diagnose, and screen for diabetes, and describe the present and future load of diabetes, and to emphasize opportunities for involvement
. Type 1 diabetes mellitus (T1DM) is one of the most common metabolic condition in infancy. Data on incidence of childhood onset T1DM are very limited. Data from large epidemiological studies worldwide indicate that on an annual starting point, the generally enlarge in the occurrence of this metabolic disease is around three % and about 78, 000 children below age fifteen years develop T1DM globaly .
The worldwide geographic difference in the incidence of T1DM is outstanding. The overall consistent incidence varies from 0.1/100 000 per year in the in China to more than 40/100 000 per year in Finland in children beneath the age of fifteen years . the variation in incidence can hardly be explained by genetic factors alone. Environmental factors have long been implicated in the pathogenesis of T1DM both as originator and potentiators of pancreatic ?-cells destruction .
Among Eastern Mediterranean and Middle Eastern countries, the biggest contribution to the total amount of estimated childhood T1DM from Egypt which accounts for about a quarter of the region’s full amount. The incidence varies between 1/100 000 per year (Pakistan) and 8/100 000 per year (Egypt) in children below fifteen years.
Egypt is located on the northeastern place of Africa and has the largest resident population amongst the Arab countries.. Egypt is divided into 28 governorates, 9 of them located in the Nile Delta .
A diagnosis of T1DM was made in a total of 1,600 patients in the 0-18 year age at MUCH above a age of eighteen years starting on 1 January 1994 and ending on 31 December 2011. Annual numbers of diagnosed cases were found to increase over many years, getting peak levels in 2008, 2010 and 2011 . The mean age at T1DM diagnosis was recorded at 12 and 10 years in females and males, respectively. All patients originated from the Nile Delta governorates at Northern Egypt. The group included 1162 patient from Dakahlia (72.6%), 175 from Damietta (10.9%), 50 from Kafr el-Sheikh (3.12%), 155 from Gharbia (9.6%) and 58 patients were from other governorates (3.78%).

Screening
Childhood-onset T1DM is a serious, with severe complications, in addition to its health condition and resource implications. The present study enrolled 1600 patients in the 0-18 years age set by T1DM above a age of eighteen years (1994-2011) in the Nile Delta region, which is compactly peopled and urbane regions in Egypt. measured age-attuned T1DM incidence in 1996, 2006 and 2011 was 0.7, 2.0 and 3.1/105/year, respectively, while age-adjusted T1DM prevalence in the similar years was 1.9, 15.5 and 26.8/105/year, respectively
This study demonstrates that childhood T1DM incidence in the Nile Delta section of Egypt is like to that in the “near to the ground incidence” class of the WHO Diabetes Mondiale (WHO DiaMond) project categorization
In Egypt, epidemiological studies for infancy T1DM are incomplete. The occurrence of T1DM was estimated at 109/105 and 112/105 in children of school age in the Heliopiolis and El-Manial regionsof Cairo, respectively.
In Africa and Middle East, data concerning the epidemiology of childhood-beginning T1DM are also light. The incidence in our pediatric population from the Nile Delta section were lower than those reported from bordering countries including Sudan (10.1/105) , Libya (7.8/105) , Tunisia (6.76/105) , Saudi Arabia (27.5/105) ,Kuwait (20.1/105) and Turkey (7.2/105) .
The geographical variability in the incidence of T1DM may be explained by genetic variations. It is fixed that genetic factors, influence the susceptibility to T1DM; however, the increases in T1DM disease incidence observed in many countries in recent years cannot be explained by genetic factors only and T1DM incidence can vary a finding which emphasize the function of the atmosphere in disease evolution.
The low incidence of T1DM in the current study can be explained by the fact that the Egyptian population lives in areas with rich and tolerable exposure to sunlight all over the year. This theory is supported by the reported negative association between average daily ultraviolet B radiation (UVB) contact and subsequent endogenous vitamin D fabrication and the sequential incidence of T1DM . though, the finding in Sardinia -Italy’s high incidence of T1DM despite high levels of UVB contact- is not in agreement with this theory .
The occurrence of childhood T1DM is not same at all ages. In most registries, the classic pattern of T1DM occurrence by age showed that the incidence inmprove with age and peaks usually in the before puberty stage with the associated gender effect which starts 1-2 years earlier in girls compared to boys . In children under age 15, reported a higher risk of developing T1DM in the 10-14 year age group, while the age group 5-9 years had a medium risk and the age group 0-4 years had a lower risk. The age group 10-14 years had about double the threat of developing T1DM compared to children less than 5 years and this trend did not vary by gender. However, this is not a consistent observation since an enlarged incidence of childhood T1DM in the age group younger than 5 years compared to the older age groups has been reported in a multicenter study for childhood T1DM in Europe .
In our study population, more patients presented at twelve and ten years of age for females and males, correspondingly. In the total patient populace and as well in both genders, T1DM occurrence increased significantly with age, reaching a peak in the age group 6-10 years, before declining to a much lower rate in the age group 11-18 years.
However, information from Tunisia , Kuwait and Turkey (males only) showed that the occurrence of T1DM peaked in the age group 10-14 years and peaked in five -nine years in Turkishe females only
Although boys and girls in general have a like risk of T1DM under age 15 ,some reports from Europe suggest a female majority in lower-risk people and slight male overload in the high-risk groups .In a recent data analysis, additional males were start to develop T1DM at younger ages, even as females predominated throughout the peripubertal age.
The current study show a significant female preponderance among the total patient population in both rural and town areas, but only in the age group 6-10 years. Our results appear to be in line with literature data where female predominance was significant among Libyan Saudi and Turkish T1DM patients. merely a slight and not noteworthy superior incidence of T1DM in Sudanese females and Kuwaiti males was reported, while no gender difference was observed among Tunisians
In the literature, there is conflicting evidence as to whether the prevalence of T1DM is lower or higher in children living in rural areas. We suppose that definite environmental and not yet identified, vary between urban and rural areas and probably explain these differences in the prevalence
In the present study, the significantly higher T1DM occurrence in rural areas can possibly be attributed to accidental exposure of children living in these areas to certain environmental ?-cell toxins such as organophosphorus compounds (OPCs) including insecticides, rodenticides and pediculicides (malathion). This explanation is supported by the reported epidemiological evidence that exposure to certain environmental chemicals is implicated in T1DM pathogenesis through direct ?-cells destruction or initiation of T1DM autoimmunity in humans
In a recent preliminary study conducted for the first time in pediatric patients (age group 1,2-10 years) at our part for assessment of the possible relationship between T1DM in children and contact to pesticide, the authors demonstrated measurable amounts of several pesticide remains in the serum of newly detected T1DM Egyptian children and malathion was reported like the most prevalent pesticide encountered
In the present study, the rate of T1DM diagnosis was relatively high and even among the months of November and March (equivalent to winter and early spring). In addition, a peak was observed in July in urban areas in male patients. The lowest rate of newly diagnosed T1DM children was documented in May. The month of May is the start of the summer holidays and the lack of school stress could provide an explanation for this low rate. However, we cannot explain the peak of T1DM occurrence observed in male urban boys. Seasonality in T1DM diagnosis has been extensively studied, but the results are conflicting. Some studies have found evidence for seasonality, while others have not). Seasonality in T1DM diagnosis was confirmed in our study between the total patient inhabitants and in both genders singly during the winter-autumne period. However, this model of seasonality was evident only in the age group 6-10 years and female predominance was observed only in winter and spring. Our result appears to be in line with the outcome of studies accounted among Sudanese , Libyan ,Tunisian), Saudi and Kuwait children where more new cases were diagnosed as T1DM in the cooler months of the year. In contrast to our observations, older age groups and males appear to be more prone to exhibit seasonality in T1DM occurrence in some studies .Different suggestions were made to explain seasonality in T1DM diagnosis; seasonal viral infections (e.g. enteroviruses, rotavirus, mumps, rubella, cytomegalovirus) have been implicated in the etiology of T1DM). Higher food intake and less exercise have also been suggested to play a precipitating role in T1DM occurrence in winter period).
Endly , the outcome of the present study indicate that T1DM occurrence and frequency showed a progressive increase over period of eighten years among children from zero to 18 years in the Nile Delta district. elevated T1DM incidence was pragmatic in rural areas and female predominance was evident. Seasonality in T1DM diagnosis was documented with a crest occurring in winter. Our remarks confirm the need to develop a nationwide registry for T1DM and the need for furtherr epidemiological investigate studies wrapping the whole country to classify the countrywide T1DM incidence and the related health data in Egypt.