Discuss the testing strategies for detecting infection with human immunodeficiency virus (HIV)
What will be an ideal response?
The earliest markers to appear in blood after infection with HIV are viral antigens and viral nucleic acid. The most
sensitive antigen test available is for the p24 antigen. Since HIV is sequestered in T helper cells during its
replication phase, nucleic acid and antigen from HIV are present in very small amounts. Once antibody to HIV
develops, it is in higher concentration and easier to detect. Thus antigen and nucleic acid testing are generally
reserved for testing specimens negative for anti-HIV when there is a concern that the person has been exposed but
has not yet seroconverted. Standard antibody screening employs enzyme immunoassay with recombinant viral
antigens to capture antibody in specimens. False positives can occur if the specimen contains antibodies to the cell
lines used to produce the recombinant antigens. Therefore, to be interpreted as positive, specimens must test
repeatedly positive by enzyme immunoassay and also positive by Western blot/immunoblot. In later stages of HIV
infection, CD4+T helper cell counts are useful to quantify immune system impairment.
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One factor that has been shown to decrease demand for cigarettes is _____.
A. an increase in cigarette cost B. a higher concentration of nicotine in cigarettes C. the popularity of filtered cigarettes D. the popularity of pipes
An incision into a vein with a needle to withdraw blood for analysis is known as:
A) intravenous. B) phlebotomy. C) phlebitis. D) phlebectomy.
The medical term for suffocation is:
A. asphyxia B. epistaxis C. URI D. tuberculosis
Gtt ____________________
Fill in the blank(s) with correct word