Transmission of HIV
Acute infection
Asymptomatic period
AIDS-related Complex, or ARC
The effects of HIV infection on the body have been studied thoroughly. Many studies have followed people who engage in high-risk behaviors, from before they were infected, through the entire course of the infection, to the final stage of AIDS. We now know the usual course of HIV infection with considerable precision.
In most people, HIV infection follows a clear course: transmission of the virus is followed by an acute infection that clears up spontaneously; then there is a prolonged period during which the person feels good and has no symptoms of infection, that is, is asymptomatic; the person
gradually develops the symptoms that are sometimes called AIDS-related complex, or ARC; eventually, the person develops the disease referred to as acquired immune deficiency syndrome, or AIDS, which is defined by the presence of a variety of other infections in many different parts of the body, the so-called opportunistic infections.
Based on extensive studies, researchers have determined the duration, on average, of each stage. Individual people, however, spend widely varying amounts of time in each stage. Some people with positive HIV blood tests have remained healthy for over ten years, though most have declining numbers of CD4 cells, suggesting some suppression of the immune system.
The course of HIV infection is generally as follows:
Transmission of HIV, usually by blood exposure or through sexual intercourse.
Two to six weeks: Acute infection, meaning the development of an infectious
mononucleosis-like illness from which people recover in one or two weeks. Some people do not even notice this stage.
Four to twelve weeks, sometimes longer: Seroconversion, that is, the body develops antibodies to HIV, and as a consequence, the results of the blood test for the presence of antibodies to HIV are positive.
Asymptomatic interlude, during which the person feels well and functions normally except for the psychological stress that accompanies knowledge of a positive test.
Five to eight years, with considerable individual variation: symptoms of AIDS-related complex, or ARC. Some people never develop ARC but progress directly to AIDS.
Eight to ten years: AIDS as defined by diagnosis of an opportunistic infection, opportunistic tumors, or AIDS dementia.

Type 1 diabetes is a genetically determined disorder, with an increased incidence in monozygotic twins and first-degree relatives or people with type 1 diabetes. Approximately 70% of monozygotic twins develop type 1 diabetes (with prolonged follow-up), and a first degrees relative of a person with type 1 diabetes has approximately one chance in twenty (5% risk) of developing the disease (vs. 1:300 in the general population). The responsible genes are within the major histocompatability complex (MHC) located on chromosome 6 (also called the HB locus). About 40% of the familial aggregation of autoimmune type 1 diabetes is explained by MHC genes, especially HLA class II molecules DQ and DR. Ninety-five percent of type 1 diabetics carry HLA D3, Dl or both compared with 45% of the general population. The presence! an aspartic acid residue at position 57 of the DQ 3 chain is protective for the development of type 1 diabetes. Clustering of long-term complications in families studied in the DCCT suggests that a genetic component contributes to vascular complications.

Cervical Cancer
The number of women this disease killed in the United States dropped from 8,487 in 1960 to 4,627 in 1990. A major cause was early detection with the help of Pap tests and treatment with surgery. There is controversy about the effectiveness of Pap tests, but deaths from cervical and uterine cancers have fallen more than 70 percent since the introduction of the tests in the 1950s, reports the College of American Pathologists. Sexually active women (especially those with more than one partner) would do well to have three successive yearly Pap tests. If each test result is negative, a test every three years is then advised.
Genital warts (papilloma) warn women to get a Pap test. The warts are caused by viruses that may also cause cervical cancer. Prompt removal of these warts is urged for men and women.

Ovarian Cancer
Can screenings detect ovarian cancer early enough to remove it? Dr. Eyre says researchers are trying to determine that answer: “We are testing the effectiveness of pelvic exams, a blood test for a substance called CA 125, as well as a sonar examination of the ovaries.”