The Michigan Daily - Friday, January 27, 1995 -3 Detection methods help control spread of deadly virus Stories By Kelly Feeney Daily Staff Reporter The HIV-antibody test is the one test that can be called the ultimate "killer." Uncontested in the fear, anxiety and stress it causes, the test's eventuality cannot be avoided. Living in the age of AIDS, the reality is that someone we know - and perhaps our- selves included - will someday have to be tested for this deadly virus. The HIV-antibody test, commonly referred to as the AIDS test, is a blood test that detects HIV antibodies produced when the body has been infected with the Human Immuno-defi- ciency Virus (HIV). Because HIV is the virus that can develop into AIDS (Acquired Immuno Deficiency Syndrome) the results - either HIV-positive or HIV-negative - can have profound affects on a person's future. In 1992, 2.7 million HIV-antibody tests were administered at public clinics in the United States. Since the test was approved in 1985, the number of tests has annually in- creased and has entered the mainstream of health concerns. At University Health Services (UHS) in 1993, 1,049 people were tested for the virus - with 75 to 80 percent of the tested persons being students. The HIV-antibody test is important not only because it detects the presence of HIV - which, if detected early, can stop the threat of AIDS developing - but also because of the preventative measures the test takes. As part of the testing process, patients receive counseling on HIV risk factors, how HIV is spread and safer sex guidelines. Stud- ies have shown this counseling increases a patient's knowledge of HIV transmission, which can decrease the transmission of the virus and other sexually transmitted diseases. For college students, whose sexual prac- tices are often "risky" - having multiple sex partners and not practicing safe sex - the HIV test takes on special importance. It not only helps to educate, but it serves the imme- diate need of allaying the fear of possibly being infected. The idea of being tested for a virus that can cause death doesn't sit well with many stu- dents-mortality and youth have never mixed. Yet understanding how the HIV-antibody test works is crucial. As the number of AIDS rcases increases and a vaccine is still to be found, knowing who carries the virus is the only way to curb its spread. Students and Testing at the "U" Since 1987, University Health Services has provided free HIV-antibody testing and coun- seling to students. Conducted anonymously or confidentially, the test from the initial blood work to lab analysis takes two week. "Most of the students we test are average college students, who have a sophisticated knowledge as to how AIDS is transmitted," said Jen Stewart, a health promotions officer who oversees testing and counseling at UHS. Stewart indicated that students know how Detecting a Debilitating Disease Two tests for detecting HIV, the virus that causes AIDS, have become the first steps in recognizing the disease. Both tests work off the theory that when HIV enters a person's body, the immune system immediately responds by forming antibodies. Here's how they use the information. The ELISA test The enzyme-linked immunosorbent assay test detects the presence of HIV-1 collectively labeled HIV, in the patient's blood serum. Actual HIV antigens are produced in laboratories and used to coat the inside of a test tube. v'~' /' Blood serum from the patient is added to the test tube. If HIV antibodies are present, they will bond to the antigens. t and HIV-2 antibodies, An anti-human antibody, which is labeled with an enzyme, is injected into the test tube and will bond with the HIV antibodies. 6 u4 lust a Review Here are some of the important terms when talking about AIDS. AIDS - Acquired Immune Deficiency Syndrome. It attacks the body's - immune system, making it impossible to fight off even the simplest infections. HIV - Human Immunodeficiency Virus, the disease that causes AIDS. It is spread through bodily fluids and cannot survive outside the body for any extended period of time. Antigen - Produced by the body to fight a virus. Appear early, but are expensive to detect. Antibody - Work through antigens to kill a virus. Develop later, but are much easier to find in chemical tests. Where to get tested University Health Services, 207 Fletcher St., Ann Arbor. 763- 1320. Planned Parenthood, 3100 Professional Dr., Ann Arbor. 973-0155. Washtenaw County Health Dept., 555 Towner, Ypsilanti, 484-6760. AIDS Hotline, 1-800- 342-AIDS(24 hour). CDC AIDS Hotline, 1- 800-342-2437. A substrate, which "locks" to the enzyme, is added to the serum specimen and causes the solution to change color. By measuring this color change, doctors can detect the HIV antibodies. The Western Blot test This test, used to confirm a positive ELISA test result, also relies on a color change. Electric current is passed through the sample, which causes the HIV antigen fragments to separate with the larger, darker bands to float to the top of the sample. The distance travelled by the dark band determines if the sample contains HIV antigens. False Positives While these tests have become more accurate over the last few years, they are still only about 99 percent effective, meaning that 1 of every 100 tests will come back incorrect, possibly resulting in a positive test for someone who is HIV negative. Much rarer is a negative for someone who is HIV positive. False readings may also occur if the test is performed less than six months after possible exposure. Doctors strongly recommend anyone who tests positive seek medical evaluations. JONATHAN BERNDT/Daily to have safe sex, but "putting it into practice" is where they have difficulty. Consequently, students get tested because they have doubts and concerns that they may be infected. Many students UHS tests indicate they've had unprotected sex once or sex while under the influence of alcohol. Some have had unpro- tected sex numerous times. Some couples get tested together before beginning a sexual rela- tionship. Before any blood is drawn and analyzed, students are required by state law to receive counseling. UHS offers m ost both a half- hour pri- vate and an hour-long averag e,, group session. In each session, students and sophisic counselors discuss -i ways to reduce risk fac- tors of becoming in- fected, safer sex meth- ods and any other con- cerns or questions the student has. Ninety-five percent of students are tested anonymously. No personal information is re- quired of the student who chooses to be tested anonymously, and no written record of the test is kept. Test results are obtained by the student using a number as identification. If the student needs written confirmation of the test, usually for employment purposes, a confidential test in which the results are only released to the stu- dent and kept in his/her's medical chart is administered. One LSA student, who was being tested anonymously, expressed anxiety at not know- ing whether she was HIV-positive. She decided to take the test to confront reality and her fears. "Knowing that I'm being ignorant is what's making me get tested," said the student, who had unprotected sex. One night, about six months ago, after hav- ing unprotected sex in a monogamous relation- ship, the student sat up all night "checking my calendar so that I could mark the date, six months later, when I could be tested," she said. She realized that she had to face reality her partner's previous sexual relationships may have infected him, and then her, unknowingly. The reality that she might have HIV was too overwhelming and stupid not to confront, she said. UHS tests results mirror the national aver- age - about two in every 1,000 people test positively. Even though nearly all tests result nega- tively - only 49 HIV-positive cases have been reported to UHS during the past eight years - the actual number of HIV cases may of the students we test college students who ht ated knowledge as to h fitted. " UHS Hf be higher, and increasing, but the people who have it may not be getting tested. And though a 1990 report issued on the prevalence of HIV among college students found the rate of infection to be only 0.2 percent, no one knows for certain the magni- tude of the virus' threat. "We can know the number of tests admin- istered and the results, but we don't know the prevalence in the population," Stewart said. Though she said that not knowing the preva- lence in the population is "the crux of testing," she said the test can help people to learn their status and more importantly can educate them. "But the important thing is to give people the opportunity to learn. The key to prevent- ing HIV is education," she said. The Test and Results The HIV-antibody blood testis not an AIDS test - and the result, if it is positive, is not a diagnosis for AIDS. The test only detects HIV antibodies. Clinical procedure of the test involves drawing a small blood sample from the patient, upon which two different tests are conducted. The ELISA (Enzyme-Linked Immunosorbent Assay) is the first test run on the blood sample. As a sensitive screening test, ELISA tests blood serum for HIV-I and HIV-2 antibodies. If antibodies are detected, the test is re- peated a second time on a different blood sample. If the second examination indicates that antibodies are present, there is a high probability that the person has been infected with HIV. But a sec- ond test is needed to are confirm the ELISA result. ave a The Western Blot test is the con- ow AIDS firming factor in de- tecting the presence of HIV-antibodies in - Jen Stewart the blood serum. It not only detects the V-testing officer presence of antibod- ies mounting, but it also gives insight into what antigens the body has produced in re- sponse to the virus entering the body. A positive Western Blot result confirms that the body has been infected with HIV and is producing an antibody reaction. A negative results mean antibodies are not present. Because the Western Blot test is the more conclusive of the two tests, a negative West- ern Blot result can negate an ELISA positive result. Though rare, an initial indication of HIV-antibodies reported with the ELISA test can turn out to be false. In the beginning days of HIV testing the discrepancy between the two test results was greater. Today, the two tests give correct result 99.8 percent of the time. At UHS, Stewart said if a person tests positively, another test is conducted to con- firm the results, and partners can be notified anonymously to learn if they are infected. Yet, patients should beware of a negative test result - they are not yet clear from risk. Research indicates that a majority of people will begin developing antibodies within three months after infection - yet it can take up to six months for antibodies to appear. If a person is tested during the "window period" - a time too early to begin detecting antibodies - he or she may mistakenly think the virus has not infected the body when'it may have. "During that window period, people think that they're home free, but that might not be true," said Barry England, director of the Ligand Assay Laboratory at University Hqs- pitals. "You may be infectious and infect someone else when you think that you're safe. "Most people don't get tested until they think they may have been exposed and in- fected," England said. But, he warned, "If you get exposed, that's it. "The implications are that you have to be extremely careful all the time. What's so terrible about the disease is that in the early stages there are no symptoms," England said. Also during the early stages, particularly during the primary two months, a person is most infectious, according to a study released by a team of University researchers earlier this month. If a person engages in sexual activity, it is important to realize the risk and plan to get tested. If not, according to the study, the person has a higher chance of spreading the virus to more people if risky behavior contin- ues. "The most dangerous person is not seropositive. The most dangerous person is seronegative who is having outside relation- ships," said James Koopman, a professor of epidemiology and one of the three University researchers who completed the study. Until a cure is found ... AIDS may well in fact prove to be the curse of generations to come - and its presence today seems to affect more and more people's lives. With a cure and vaccine still still to be found, the only way to stop the spread AIDS is through prevention. The HIV-antibody test doesn't have to-be a "killer" - but can be if people don't learn the lessons of prevention. AIDS Stats 'U' students trained in AIDS risk assessment Number of tests administered at public clinics (1992): 2.7 million Approximate number of people with HIV:1 million Number of AIDS cases reported to the Center for Disease Control (June 30, 1994): 401,749 Number of cases, ages 13-19: 1,768 Number of cases, ages 20-24: 15,204 Number of cases, ages 25-29: 60,042 Total AIDS related deaths: 243,23 Talking about sex with a stranger makes many people feel uncomfort- able- even when that stranger is a doctor. Because of the uneasiness and tension felt by both patient and doctor toward the subject, the sexual history examination is one of the most uncomfortable aspects of as- sessing AIDS risk. Sometimes thought of as "uncar- ing" and "cold" in their medical pro- cedure, doctors face even more scru- tiny when examining a patient's the medical students to hone their communication skills. The program, titled "Introduc- tion to the Patient," runs throughout the four years of medical school. The second year emphasizes taking patient sexual histories and making AIDS risk assesment. "It's well known that it is diffi- cult to broach this kind-of subject," said Dr. Andrew Zweifler, one of the program's coordinators, adding that students must be able to over- take in their own lives to decrease the risk of infecting, or becoming infected, with HIV and other sexu- ally transmitted diseases. A simulated sexual history inter- view with "patient instructors" - who are usually other University students - allows the medical students to prac- tice different techniques. During the interview, doctors must ask the "patient" questions about his orher sexual history, which has been created for them. and understand the problems the patients are facing. AIDS risk aware- ness is also very important on the patient-instructors' eyes. Lisa Lowery, a medical student in the program, agreed. "You have to remember that there is a person behind the patient," she said. For her, the interview is stress- ful, but it provides a great opportu- nity to practice the skills she and her classmates are going to need in the future. A 1 nn ., a1. 1 . i .,s. , rA