Background: Babesiosis in an entity transmitted by tick bite presented in our medium producing high morbidity and mortality in immunodepressed patients.
Methods: The prevalence of ticks infected with bovine Babesias was studied in a sample of 104 ticks collected from cattle for alimentation in the Sierra of the Autonomous Community of La Rioja.
Results: 3.84% of the ticks studied (3.3% of 89 Ixodes ricinus and 6.6% of 15 Dermacentor marginatus) presented Babesias in the hemolymph by Giemsa staining.
Conclusions: A sizable degree of parasitization by bovine Babesia was found in the ticks of the medium studied. Given the possibility of parasitization by these parasites, babesiosis must be included in the differential diagnosis of the febrile hemolytic conditions seen in our environment.