Background and aim of the study: Toxoplasmosis is one of the neglected infections which has a global distribution. Effective treatment against ‎toxoplasmosis is hard to accomplish. Accordingly, we tried to investigate the effect of using vitamin D₃ alone ‎and in combination with nitazoxanide in Toxoplasma gondii infected mice‎‎‎‎‎.
Materials and Methods: The study was conducted on 100 Swiss albino mice which were infected with the avirulent (ME49) Toxoplasma gondii strain. Mice were equally divided into 5 groups: (GI): Infected untreated control group; (GII): Infected and treated by spiramycin; (GIII): Infected and treated by vitamin D₃; (GIV): Infected and treated by nitazoxanide and (GV): Infected and received a (vitamin D₃ –nitazoxanide) combination. The therapeutic impacts of drugs were assessed using; parasitological, histopathological and immunological approaches.‎
Results: The study showed that the vitamin D₃- nitazoxanide combination induced a significant reduction in the parasitic load in the brain sections of the infected mice. We have also reported a delicate balance in the overall immune response against the parasite after using the drug combination. It was noted thatvitamin D_3, used alone, did not significantly reduce the parasitic load despite the notable improvement in the degree of inflammatory infiltration.
Conclusion: The present study revealed that the vitamin D₃–nitazoxanide combination was highly potent in restricting the parasitic load. It controlled the infection without the harmful immunopathological impacts. Thus, vitamin D₃ could be a valuable candidate, either as a sole agent or as an adjunct to other anti-parasitic therapies, in areas where toxoplasmosis is endemic‎‎‎‎‎‎‎.