Recurrent or chronic
fever is seen
in typhoid, tuberculosis, hepatitis, SLE, rheumatoid arthritis, Polyarteritis nodosa (PAN) and other auto immune disorders, UTI, drug fever, sinusitis, glandular fever, otitis media, IBS, HIV, STDs, endocarditis, parasitic infestations (like malaria), fungal infections, lymphomas and other cancers etc. It can even be diabetes and hyperthyroidism.
With repeated infection, I am sure your diabetes status has been checked.