Individuals with HIV may remain symptom free for a number of years. The first signs of infection are usually enlarged lymph nodes. Other signs will develop over time due to decreases in immunity. These infections include thrush in the mouth or upper throat, shingles involving two episodes in more than one skin area, pelvic inflammatory diseases and listeriosis among others. The number of illnesses increases as the CD4 count falls. HIV infected individuals are also at risk for many malignancies including cervical cancer and primary brain lymphoma.