Hello, thanks for using health care magic Fever in most cases indicates an infection which could be bacterial or parasitic like in the case of malaria. It would have been more helpful if you listed all the tests you have done so far and the results. C-reactive protein is an important test to rule out bacterial infections together with white blood cell count. The malaria test you did, if it was microscopy then there is a chance of having a false negative result unlike if the test that was done was a rapid diagnostic test. You should do C-reactive protein test, if its positive with an elevated white blood cell then its a bacterial infection. On the other hand if they are negative then you should do a rapid test and consider treating for malaria. Rare causes of fevers are tumors. Hope this helps you. Dr Achuo