A CD4 count is not required in conjunction with every viral load test. Viral load testing is a better indicator of a patient’s response to therapy. CD4 monitoring is not necessary for patients who have stable viral suppression. For the first two years after treatment initiation, the CD4 count should be monitored every three to six months. After two years, if the viral load is undetectable, the CD4 count should be measured yearly if it is 300–500 cells/mm3. If it is consistently above 500 cells/mm3 then further monitoring is optional.