Enteric fever, Dengue and malaria still remain diseases of public health importance in the tropics. Individuals residing in endemic areas are at risk of contracting these infections either concurrently or an acute infection superimposed on a chronic one. This study was undertaken to document patients showing co seropositivity for Enteric fever, Malaria and Dengue and to record the baseline Salmonella antibody titer in voluntary blood donors who represent general population of the area. The present study was conducted in the Department of Microbiology, J.J.M. Medical College, Davangere. Among the 824 febrile patients enrolled with positive serological test for either Typhoid, Dengue or Malaria, 189 patients were found to have co seropositivity to any two of the above diseases on subjecting their serum to Widal test, Dengue ELISA and malaria antigen detection by immunochromatography. A total of 189 patients showed co seropositivity for any of the above mentioned diseases accounting for 22.90%. Typhoid-Dengue was found in 9.83% Typhoid-Malaria in 6.67% and all the three in 0.48%. Dengue- Malaria co-seropositivity was recorded in 5.94%. The basal titer in healthy population was found to be <1:20. The co seropositivity rate in our study is 22.9% which poses a challenge in the diagnosis and treatment of such patients. As the gold standards culture and microscopy are time consuming and molecular diagnostic tools not a practical reality in many rural and developing primary health centers, simple, rapid and sensitive serological methods are being used as an alternative diagnostic tool in diagnosing atypical co infections which in some instance leads to overwhelming diagnosis of co infections and improper treatment.