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Frerichs, R.R. Routine Hospital HIV Testing and Prophylactic AZT

SEA-AIDS Network, December 3, 1997

R.R. Frerichs Posting

Internal disagreements often make it difficult for organizations or groups to focus on common goals. One clear example is HIV antibody testing, which some support but others feel is controversial and should only be done in special circumstances. In the debate on individual rights to avoid disclosure versus community rights to avoid further transmission, the broad goal of HIV control is often overlooked. Even defining criteria for HIV antibody testing has met with resistance, as people prefer to think about other topics that are less contentious and easier to resolve. Nevertheless testing issue will not go away, especially for countries like India, Myanmar, Thailand, Cambodia and parts of China and Vietnam where HIV is becoming increasingly common. Such countries must develop coherent testing policies if the epidemic is to be controlled.

Earlier I wrote to SEA-AIDS of the need to develop mechanisms for testing of pregnant women, so that efforts can be made to avoid mother-to-child transmission. Now in the current issue of the New England J of Medicine (i.e., NEJM 1997; 337, 1485-1490, 1542-1543) comes another reason for testing in countries where HIV is common. The case-control study of health care workers focuses on factors that contribute to the spread of HIV to health care workers from their HIV infected patients. The CDC-led team reported that there are four main factors associated with HIV transmission from patient to care giver:

  1. deep injury, injury with a device on which the source patient's blood was visible,

  2. a procedure involving a needle that had been in a source patient's artery or vein, and

  3. exposure to a source patient who died of AIDS within two months after the incident.

Most relevant to this posting, they found that zidovudine (AZT) prophylaxis is apparently protective, in that the case subjects (i.e., health care workers who became HIV infected) were five times less likely to have received zidovudine following exposure than control subjects (i.e., health care workers who did not become infected). This suggests that after inadvertent contact with the blood of HIV infected patients, immediate AZT use may reduce HIV transmission by up to 80%.

So how is a doctor or nurse to know that AZT should be immediately used? If they regularly treat themselves with AZT after every contact with blood, regardless of the HIV status of their patients, then both cost and viral resistance will become complicating factors.

Conversely if they routine test all patients at admission with newer rapid tests, they will know who to manage with greater care, and when to use prophylactic AZT if accidents happen. 

Medium to high HIV prevalence is what justifies routine HIV testing at hospital admission. Thus such testing would likely not be considered in countries where HIV is uncommon. What do health professionals in higher prevalence countries think about routine HIV testing of hospitalized patients? Is some level of accidental transmission from patient to physician or nurse acceptable, so as not to jeopardize patients' rights to have HIV status remain free from disclosure? Do patients who come into a hospital setting have such rights or is protection of hospital personnel of greater importance?

Please share your criteria for deciding if routine testing in medical settings is justified.