Dear Doctor, Under what circumstances should one consider going for an HIV test and how often should one take the test? What are the physical signs that could point to a person infected with HIV? The Centre for Disease Control and Prevention recommends testing for all people from 13-64 years at least once for HIV infection. High risk groups need more frequent testing. These include sex workers, partners of HIV infected persons, health professionals exposed to body fluids of HIV/AIDS patient and persons nursing an AIDS patient, among others. HIV testing is also routinely done during pregnancy to prevent mother to child transmission. Signs which are suggestive of HIV/AIDS include; unexplained weight loss and wasting, unexplained prolonged fever or diarrhoea,swelling of lymphatics in neck, arm pits and or groins, recurrent sore throat, ear infections, ulcers or sores in or around mouth, recurrent or persistent fungal infections in the mouth or on body. Underlying HIV infection is always considered as a possibility if somebody has grave and atypical infections like miliary TB, cerebral toxoplasmosis, pneumocystis pneumonia, etc. HIV patients are more prone to malignancy like lymphomas, kaposis sarcoma. In all such conditions, the patient is tested for HIV.