A revealing study in the early eighties compared needlestick exposures between San Francisco General Hospital, which had a high prevalence of HIV infected patients, and Grady Memorial Hospital in Atlanta, which did not.¹² The exposure rate was much greater at Grady, suggesting that health care workers were more careful around the higher HIV population. The message should be that if all patients are considered potentially infected with HIV, safer techniques are practiced. Experience has shown that we are always careful around the documented HIV-infected patients, but not around those we don't suspect, which represents the greatest risk.

Screening

HIV Testing Guidelines

Individuals Recommended for HIV Testing

• Persons with STDs, TB, or hepatitis B (also HIV)
• Persons with present or past IV drug use (regardless of how long ago)
• Women of childbearing age who engage in commercial sex, have at-risk partners, or who live in communities with a high prevalence of HIV
• Persons who consider themselves at risk
• All pregnant women

With these demographics in mind, the following populations be screened for HIV: persons with STD's, past or present IV drug use, (regardless of how long ago the person claims to have stopped using), and persons who consider themselves at risk. A large percentage of people who come forward to be tested on their own volition may have a risk factor to which they may not readily admit, and adequate counseling should be provided. Other groups include selected women of childbearing age who use injecting drugs, engage in commercial sex, live in a community with a high prevalence of infection, or have at-risk sex partners.

This last category should be emphasized among physicians and counselors because it represents a significant risk category that is often not considered. Certain medical conditions that can suggest HIV infection, such as persistent fungal infections or zoster, or cause complications as a result of infection, such as tuberculosis, should prompt consideration for screening. Finally, for reasons that will be discussed shortly, all pregnant women should be screened.

The benefits of HIV testing are more relevant now than ever before, thanks to the development of more potent antiretroviral agents that have made a marked impact since September of 1995. Their efficacy is not only more durable when used as part of a first-line regimen, but are likely to be more effective overall when started in the early stages of infection, making timely diagnosis of disease all the more crucial.

Benefits of HIV Testing

• Allows early and aggressive treatment of HIV
• Allows early entry into clinical trials
• Provides opportunity for patient education
• Allows early contact notification
• Allows early prophylaxis for Pneumocystis jiroveci pneumonia
• Enables planning for health care management

HIV testing also provides the opportunity for patient education, particularly if the test result is negative. It allows for contact notification to reduce spread and permit early recognition of infection in others. Testing also enables persons to enter into health care management planning and thus reduce medical complications and address social issues that may have magnified the clinical problems.

One area that has made such a great impact in preventing infection that established guidelines are strongly recommended is that involving infected pregnant women. The ACTG 076 study found that providing zidovudine to HIV-1 infected pregnant women and their newborns reduces the risk of vertical transmission three-fold, from 25% to 8%. This has led many states to require that physicians ask ALL pregnant women under their care to be tested for HIV. ¹³

AIDS Clinical Trials Group Protocol 076
ACTG-076

A study of Zidovudine (ZDV) in Asymptomatic HIV-infected Pregnant Women N=477

• Average age                                 25 Yr
• Average CD4+ count                   550mm³
• Average gestation at entry         26 wk into study
• Reduced maternal-fetal        transmission from 25% to 8%   (P<0.001)

In situations where the woman is found to be positive, a three-part ZDV-containing prophylaxis regimen is initiated after the first trimester regardless of viral load and continued throughout the pregnancy. Women already on antiretroviral therapy who become pregnant should consider remaining on therapy. When feasible, ZDV should be part of the regimen. During labor, IV zidovudine, oral nevirapine or oral ZDV with lamivudine are options, followed by treatment of the newborn. ¹³

ACTG-076: Study Regimen of Zidovudine

During pregnancy:

• ZDV 100mg, po 5x/day, beginning @ 14-34 wk gestation and continued throughout

During labor:

• ZDV 1-hr loading dose, IV 2 mg/kg
• ZDV IV continuous infusion, 1 mg/kg/hr

For infant:

• ZDV syrup 2 mg/kg q 6 hr. beginning within 8-12 hr after birth and continued for 6 wk     
• If oral not tolerated, IV 1.5 mg/kg over 0.5 hr, q 6 hr

Recent studies involving pregnant women in developing countries have demonstrated that a single dose of nevirapine given just prior to labor is as or more effective than zidovudine in reducing perinatal transmission of HIV.