If an HIV infected person misses taking their antiretroviral medications (ART) as prescribed by their doctor, they are likely to develop 'resistance'- meaning that the drugs may stop working against the virus.
What happens now? As the virus starts growing in number, the individual may unwittingly transmit the resistant virus to someone else. Soon many of the symptoms of a weakening immune system begin again- frequent episodes of sickness, weight loss, feelings of tiredness etc. If the person is not monitored and the drug regimen switched, the person will quickly progress to AIDS.
Two tests are required to detect and solve the problem of drug resistance in this person: a viral load to measure the amount of virus and a drug resistance test which will identify exactly which drugs will and will not work against the resistant virus.
The drug resistance genotype can only be run if the viral load is close to or greater than 1000 copies/ mL of plasma. Once the genotyping is complete, the report generated will contain information about the virus' susceptibility to various antiretroviral medications as seen in the picture above.