RESUMO
Background: Under-nutrition is a global problem associated with infectious diseases including malaria. In this study, we explored the association between the newly introduced malaria vaccine, RTS,S/AS01 and measles vaccine with under-nutrition in children. Methods: We conducted a case-control study using anthropometric data for children aged between 10 and 59 months in Siaya County, Kenya collected from September to December 2021. Malaria and measles vaccines were the exposure variables, and under-nutrition, which is a composite variable including stunting and/or underweight was the outcome. Chi-square was used to test association between under-nutrition and the two vaccines. Further, a binary logistic regression was used to assess association between the vaccines, and independent variables with a confidence interval set at 95%. Results: From a total of 1,701 children, 185 (16.8%) were undernourished. Among the undernourished children, 121 (11.0%) were stunted and 64 (5.81%) were underweight. The undernourished children were matched with children of normal nutritional status at a ratio of 1:1 giving a total of 370. Malaria vaccine coverage was low at 21.1% (39/370) and 17.3% (32/370) among undernourished and children with normal nutritional status respectively. Similarly, the measles vaccine coverage was 30.8% (57/370) and 36.2% (67/370) among cases and controls respectively. Neither exposure to malaria nor measles vaccines showed a statistically significant difference between the cases and controls. Conclusions: We found no statistically significant association between malaria vaccine and under-nutrition in children. While malaria vaccine is important in protecting children from the malaria disease effects, it is not a proxy intervention for under-nutrition.