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Frerichs, R.R. Response to Acceptance of HIV Personal Screening.

SEA-AIDS Network, June 19, 1998.

Posted in response to:

SEA-AIDS, June 17, 1998

From Andrew Hobbs, Lusaka, Zambia

  1. How exactly will couples "take into account the 6-12 week antibody window period"? when they are using their litmus papers in the dark?

  2. Does social diffusion theory take account of the economic forces (e.g. drug companies) behind any innovation? Good ideas sometimes spread - profitable ideas (good or bad) always spread.

Andrew Hobbs


R.R. Frerichs Posting

This posting is in response to Andrew Hobbs from Lusaka, Zambia, appearing in SEA-AIDS on June 17, 1998. He posed a question, "How exactly will couples take into account the 6-12 week antibody window period when they are using their litmus papers in the dark?" The answer, of course, is that they will not unless they are cautious and test each other twice over a three month period.

Fortunately, the window period (i.e., when the HIV test is negative but the person is infective to others) on average lasts only a few months, a small time when considering the 108-120 months when the potential sexual partner is HIV infected but shows no sign of the virus. If a couple wants to be extra safe, they would consistently use condoms until two sets of tests are negative, done 3-4 months apart.

Some will be able to do this and they will be able over a long life to have risk-free sexual intercourse with each other. Others will not, and some of them will become HIV infected.

The second point raised by Mr. Hobbs is more provocative. He mentions, "Good ideas sometimes spread - profitable ideas (good or bad) always spread." I agree.

What will make personal HIV screening profitable in the United States and Europe is the availability of effective (but usually expensive) therapy. You cannot treat what you cannot find. Thus the desire of HIV infected persons in such societies to live will stimulate widespread testing. Since clinic based testing will be considered too cumbersome, inconvenient or intrusive for frequent use, personal HIV screening will catch on as a viable alternative in most developed countries. Those concerned with public health, however, will also benefit from personal screening, since detection will likely lead to behavior change, which will reduce secondary transmission. Thus the good idea of personal screening will spread in wealthier societies, with the "profit" being financial for drug companies and humanitarian for public health officials.

In the developing world, the good idea of personal screening may not spread because there is less incentive on the treatment side for case-finding. What is most curious in poorer societies is not the reaction of physicians and their patients to testing, but rather the neglect of testing that occurs among many in the public health community. The humanitarian benefits of testing (that is, the good of saving lives by avoiding further transmission) are the same around the world. Wealthier societies, however, have the added benefit of financial profit that comes to those who manufacturer or distribute drugs against HIV. Can public health professionals find satisfaction in testing to avoid further transmission? If the answer is "yes," then personal screening will likely be viewed as a viable intervention and prevention strategy. If the answer is "no" then epidemic will continue as before with no new options for prevention.

The fundamental question raised by the Hobbs enquiry is, "Will the good idea of testing to avoid further transmission spread on its own merit, or will effective therapy be a necessary component before detection is acceptable?" I leave this to my public health colleagues in the developing world to answer.