Final answer:
Tests used to detect the presence of a virus include EIA/ELISA, RT-PCR, PCR, and Western blot, each identifying different viral components or immune responses.
Step-by-step explanation:
Tests used to detect the presence of a specific virus include enzyme immunoassays (EIA), reverse transcriptase polymerase chain reaction (RT-PCR), standard polymerase chain reaction (PCR), and Western blot. Each of these serves to identify different components of the virus or the body's response to it. EIA, also known as ELISA (enzyme-linked immunosorbent assay), looks for antibodies or antigens in the sample. PCR and RT-PCR are nucleic acid tests that amplify the genetic material of the virus to detectable levels, suitable for identifying viruses with known sequences. The RT-PCR is specifically used when the virus is RNA-based, as it involves reverse transcription of RNA to DNA prior to amplification. The Western blot is a confirmatory test to identify specific proteins, often following an initial positive result from another test such as EIA/ELISA.