Nutritional Status and Asymptomatic Infection in Young Children in Two Different Endemic Areas after Seasonal Malaria Chemoprevention Campaign in Mali

Undernutrition represents an additional burden in Mali where malaria remains a major public health problem. A cross sectional survey was carried out in November 2018 and 2019 at the end of the Seasonal Malaria Chemoprevention (SMC) campaign to investigate the association between asymptomatic infection and nutritional status. A total of 541 children aged 6 to 59 months were included, 233 (43.0%) in Koila Bamanan (in an irrigated area with longer seasonal malaria transmission) and 308 (57.0%) in Kita. Data on parasitemia and nutritional status were collected and analyzed using logistic regression. Overall, underweight prevalence was 16.9% in Kita vs. 14.6% in Koila (p = 0.4); 25.6% vs. 40.8% (p = 0.001) for stunting and 14.9% vs. 10.7% (p = 0.001) for wasting in Kita and Koila, respectively. The prevalence of asymptomatic infection was 17.9% in Kita vs. 6.2% in Koila among children 6-23 months (p = 0.045). In multivariate analysis, anemia was associated with underweight (adjusted OR = 2.92; 95%IC [1.59-5.38]), and stunting (adjusted OR = 3.17, 95%IC [2.02-4.98]). Asymptomatic infection was associated with underweight (adjusted OR = 2.41, 95%IC [1.21-4.80]. Stunting was higher in children living in Koila (adjusted OR = 2.44, 95%IC [1.60-3.71]. However, the reduction in stunting was observed in children 24-59 months (adjusted OR = 0.44 95%CI [0.28-0.96]). A significant correlation was observed between parasite density and underweight in Kita (0.049). Undernutrition remains high among children in both areas and was associated with asymptomatic malaria infection.

Among factors associated to undernutrition occurrence in children under five years, infectious disease, especially malaria and geohelminth were mainly reported in sub-Saharan Africa countries [4][5][6]. Undernutrition and malaria are common in children under 5 years old, mutually worsen each other especially in malaria endemic areas. Their coexistence has a negative impact on child's learning, cognitive and physical development and responsible of most death in target population [5,7,8].  [9]. The authors reported that SMC has effective, safe and cost-effective to prevent malaria in target population [10][11][12] and could improve children's nutritional status in malaria endemic areas during it implementation period. This study was carried out in two endemic areas: Koila village, endemic malaria area Northeast from Bamako and Kita, another endemic area West from Bamako; to investigate the association between nutritional status and malaria after the last round of SMC and the possible effect of SMC in nutritional status in perspective to combine the two diseases control interventions ongoing.

Study Site and Participants
This study is part of pilot study on SMC implementation in

Study Design & Data Collection
The cross-sectional survey was carried out in November 2018 in Kita and 2019 in Koila, one month after the last round of SMC campaign to investigate association of children's nutritional status and malaria infection. The study protocol has already been approved by Ethical Committee of Faculties of Medicine, Pharmacy and Odontostomatology of University of Sciences, Techniques and Technologies of Bamako. After obtaining written inform consent from the parents/guardians, temperature, age, weight and height were measured in each child during physical examination, blood sample were collected to perform blood smear and measure hemoglobin level.
Blood smear was used to determine parasitemia by microscopy.
The thick blood films were stained with 10% Giemsa and examined under the ×100 oil immersion objective lens of a light microscope.
The number of asexual parasites was counted on 200 leucocytes and sexual parasites on 1000 leucocytes. Hemoglobin level was measured from whole blood using Hemocue 301. Electronic thermometer was used to determine axillary temperature. Malaria infection was defined as having a positive blood smear with Plasmodium, anemia by Hemoglobin (Hb) <11g/dl and the fever for any temperature >37.5°C. Each case of malaria or undernutrition has been referred to community health center for best management.

Sample Calculation & Data Analysis
Sample size has been estimated from the national prevalence of undernutrition among children under five years (23.1%) in Mali, assuming a confidence level at 95%, cluster effect at 2 and 10% of lost to follow up, a sample size was 542 participants. Data on parasitemia and nutrition were collected by using electronic data capture and exported in Excel 2010 and analyzed with STATA 14. Anthropometric indices were calculated with ENA for SMART.
Logistic regression was used to determine association between nutritional status of children and malaria infection. Pearson correlation was used to determine the correlation between parasite density and z-score of anthropometric indices with a significant p value at 0.05.

Asymptomatic malaria infection was defined as having
Plasmodium falciparum in blood smear without fever, and anemia was defined as Hemoglobin (Hb) <11g/dl. The undernutrition was defined by z-score < -2 standard deviation for height/age (stunting), weight/age (underweight) and weight/height (wasting) [13].

Copy@ Drissa Konaté
A significant correlation was found between parasite density and z-score of underweight children in Kita (r=0.30, p=0.049) ( Figure 1). This correlation was not significant in wasting children ( Figure 2), but a trend of small decrease in parasite density in children having stunting in both study sites was observed ( Figure   3).

Discussion
Malaria and undernutrition are frequently associated Malian children under five years and are a major cause of their mortality [14]. This study was carried out to investigate undernutrition and their association with malaria infection among children living in two endemic areas after SMC campaign. Children aged 24 to 59 months were the most represented in both sites (Table 1) (Table 1).
Undernutrition situation remains a major concern in terms of public health in both sites [3], despite the efforts of the Non- African malaria endemic areas [16,17].
Children living in a pathogenic environment where they are exposed to repeat infectious diseases contribute to nutrient deficit, leads food imbalance and thereafter undernutrition [7,14]. Also, a repetitive infectious disease quickly induces malnutrition among children already underweight in those areas [18][19][20]. A small significant correlation was found between parasite density and underweight in Kita (r=0.3, p=0.049) (Figure 1). Any significant correlation was not found between parasite density and others stunting and wasting according to anthropometric indices, but a small trend in parasite density decrease in children having stunting was observed in both sites ( Figure 3). In Plasmodium falciparum endemic areas, children having stunting and underweight were more infected by Plasmodium, but parasite density remains lower [21,22].
Seasonal malaria chemoprevention with SP/AQ decrease malaria infection and reduce Plasmodium falciparum parasite density in children. All children in this study received four rounds of SMC during malaria season. Combine nutritional interventions to seasonal malaria chemoprevention in malaria endemic areas could reduce parasite density and improve nutritional status in children [23]. Other parameters as family income, mother's characteristics, other pathologies were not investigated and could be influenced children nutritional status [24][25][26] are the limit of this study.

Conclusion
Undernutrition remains high among children in both sites and was associated with asymptomatic malaria infection. More studies are required to assess the treatment compliance during SMC and investigate another factor associated with nutritional status in children.

Declaration
Ethic approval and Consent to participate. This study as part of the ICEMR protocol was already approved by ethical committee of Faculty of Medicine, Pharmacy and Odontostomatology, University of Sciences, Techniques and technology of Bamako under N⁰2019/04/FMPOS revised. All participants given their agreement before data collection.

Consent for Publication
i. All authors read and approved the final version of the manuscript before submission.
ii. Availability of data and materials iii. Contact the corresponding author for any information about data availability.

Conflict of Interest
The authors declare any competing interests.

Funding
This study as part of ICEMR project, sponsored by the National