(1) Interruption of therapy was individually timed to occur after two HIV RNA measurements of less than 50 copies/ml without any viral load measurements greater than 400 copies/ml in between; these interruptions increased from 2 to 4 to 6 wk sequentially.

Until the viral load measurements were introduced, the CD-4 count was the main laboratory test used to follow an individual's course and to guide therapy.

While receiving ART some patients with undetectable viral load measurements may experience an increase in viral load, to a low level (usually less than 500 copies/mL blood), and then returned to an undetectable level.

Consideration should be given to the comparative risk represented by the exposure and information regarding the exposure source, including history of and response to antiretroviral therapy based on clinical response, CD4+ T-cell counts, viral load measurements, and current disease stage.

If you are receiving antiretroviral therapy: A viral load measurement is taken before you start treatment.

Another viral load measurement is taken 4 to 8 weeks after you start treatment to determine your response to the medicines.

Your doctor may consider your viral load measurement along with your CD4+ count to decide when to start antiretroviral therapy.

When the source-person is available for interview, his or her history of antiretroviral medication use and most recent viral load measurement should be considered when selecting antiretroviral medications for nPEP.

This initial measurement serves as the baseline, and future viral load measurements will be compared with the baseline.