Background
Anemia is the major public health problem and diagnosed as below the reference interval value of hemoglobin or hematocrit concentration for healthy individuals of similar age, sex, and race with similar circumstances [
1]. The threshold hemoglobin (Hb) level of under-five children for being anemic is less than 11.0 g/dl [
1]. Low consumption and malabsorption of iron-rich foods are the most common causes of under-five anemia [
2,
3]. It is prevalent in developing countries and results in poor in cognitive and motor development, low school performances, and exposes comorbid diseases [
4].
Under-five anemia is the global health problem both in its severity and prevalence. Globally, 1.6 million people were affected by anemia and 47.4% of them were preschool children [
5]. The prevalence of under-five anemia in Ethiopia was 56% [
6].
Based on study findings in Ethiopia [
7‐
22], the risk factors of anemia were stunting [
7‐
10], poor dietary diversity [
10‐
13], food insecurity [
8,
10‐
12], timely initiation of complementary feeding [
8,
11,
12], deworming [
13,
14], wasting [
7,
10], educational status [
7,
10], maternal weight [
7,
9], and antenatal care visits [
7]. From these factors, four factors (food diversity, household food security, deworming, and stunting) were sorted for designing adaptable intervention and control strategies to the local context. Additionally, these factors are more prevalent in Ethiopia and given more emphasis regarding the prevention aspects of anemia.
The report of the magnitude of under-five anemia in Ethiopia was not conclusive and consistent. The prevalence of under-five anemia was high in the Somali region (72%) [
13], whereas it was low in the Amhara region (13.06%) [
21]. There is a high discrepancy among studies and no comprehensive systemic review done on under-five anemia in Ethiopia. This review was conducted to explain and understand the differences in various studies with sex, age, and severity of anemia. Therefore, the purpose of this study was aimed to review sherd evidences regarding the magnitude of under-five anemia in Ethiopia. This study generates epidemiological data in each region of a country and it is important for program planners and policymakers.
Discussion
The prevalence of under-five anemia in this review was ranged from 13.06 to 72%. The highest prevalence of under-five anemia was from Somali region [
13] while the lowest one was from Amhara region (Gojjam) [
21]. The purpose of this review was to assess the pooled prevalence and associated factors of under-five anemia by reviewing the finding of available studies. The pooled prevalence of under-five anemia in Ethiopia was 44.83%. Anemia becomes a public health problem when the magnitude is above 5% of the population [
29]. According to World Health Organization (WHO) classifications of anemia, it is severe, moderate, and mild when the prevalence is above 40, 20, 5%, respectively [
29]. Thus, the level of under-five anemia in the current study was classified as severe. The findings of the current study is lower than studies done in Cape Verde, West Africa, 51.8% [
30] and Tanzania, 84.6% [
31]. This could be due to difference in practice of timely initiation of complementary feeding between Ethiopia and Tanzania. In Tanzania, about 84% of children were not exclusively breastfeed [
31]. Hence, early introduction of complementary feeding before six-months-old like cow milk should not replace iron-rich foods and which may result in iron deficiency anemia [
32].
This result is higher than studies done in China (22.4%) [
33], Uganda (37.2%) [
34], Colombia (27%) [
35], and Denmark (13%) [
35]. The possible explanation is in the current study area; there is a high prevalence of hookworm infestation, maternal and childhood malnutrition, malaria infection and a high number of low birth weight babies and stunted children. Additionally, it may be due to variations in socioeconomic status and infant feeding practices (such as exclusive breastfeeding and time of introductions of complementary feeding).
In subgroup analysis, the prevalence of anemia was higher among children under 2 years of age (50.3%) than for children 2–5 years of age (43.3%). This finding is supported by studies done in Ghana [
36] and Eastern Cuba [
37]. This may be because children born from malnourished mothers have poor stores of iron; infants are more susceptible to infections and diseases that result in poor absorption of iron [
38]; the low concentration of iron in breast milk and the introduction of complementary foods often occurs at this age group results high prevalence of anemia compared with children 2–5 years of age.
The finding of this meta-analysis revealed that male under-five children had a higher prevalence of anemia (31.3%) than females (26.8%). This finding is similar to a study done in India [
39], but not supported with a systematic analysis of the global anemia burden [
40]. This difference could be due to it appears almost entirely driven by the excess prevalence of male anemia resulting from hookworm while excess anemia in females at other ages was related to iron deficiency. Therefore, children should be restricted to barefoot during playing and avoid playing with mud.
In this study, anemia is the major public health problem of the population. The contributing factors for under-five anemia were poor food diversity, food insecurity, stunting, and not dewormed. Children who fed less than four food groups per day were 1.71 times more likely to develop anemia than their counterparts. Similarly, food-insecured children were 2.87 times at high risk to develop anemia than secured ones. This finding is supported in studies done in Italy [
41] and middle-income countries [
42]. This could be due to children from food insecurity households lack nutritious diets that have high protein quality, adequate micronutrient content and bioavailability, macro-minerals, iron, and essential fatty acids that increase the likelihood of childhood anemia [
43].
Children who were stunted were 2.54 times more likely had anemia compared with children who were not stunted. Additionally, children who were not receiving anti-helminthes were 2.34 times more likely to develop anemia than dewormed ones. This finding was consistent with studies done in Tanzania [
44], Vietnam [
45], Cambodia [
46], and Northwest Uganda [
47]. This is the general fact that stunting is a consequence of malnutrition and it is a significant risk factor for anemia. Similarly, helminths destroy red blood cells and decrease their lifespan, which is reaching in hemoglobin and finally results in anemia. Therefore, deworming infants every 6 months is the best option of the prevention mechanism of under-five anemia.
Conclusion
The pooled prevalence of under-five anemia was classified as severe. Therefore, supplementation and fortification programs of foods, periodic deworming, feeding diversified food, and secured food households are strongly recommended to alleviate under-five anemia.
Publisher’s Note
Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.