POSTING 3: MORE ON EARLY DETECTION 


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Frerichs, R.R. More discussion on early detection

SEA-AIDS Network, April 2, 1996

Posted in response to:

SEA-AIDS, March 31, 1996

In an attempt to 'compress' the discussion on the 1997 conference theme, several postings have been sent together.


From Nicholas Prescott, World Bank

I wish to endorse and emphasise the significance of Chris Green's comment highlighting the low probability that universal early detection of HIV might induce significant health improvements in a typical developing country context.

Based upon my recent research for the Thai MOPH on the affordability and cost-effectiveness of case management options for HIV/AIDS (in collaboration with Dr Jos Perriens, UNAIDS), I would assert that:

(a) no known chemotherapy regime involving treatment of opportunistic infections and antiretrovirals at any stage of HIV/AIDS offers an expected value of extended survival beyond about 1.25 years compared to no treatment;

(b) the likely out-of-pocket cost of any recognised treatment regime would be unaffordable by the private sector -- defined as exceeding the percapita nonfood household consumption expenditure -- by all except the top three deciles of the income distribution. This assumes that antiretrovirals are fully subsidised, and that users are charged only 1/3 of the unit cost of chemotherapy for opportunistic infections, as well as only 1/3 of the cost of delivery of associated inpatient and outpatient hospital services. Note that under these generous subsidy assumptions, universal coverage of the projected caseload in Thailand is unaffordable by the public sector under existing budgetary priorities. Thus both government and household budget constraints impose a major limitation on the case management response even in the economic environment of Thailand, which is significantly better off than any other heavily affected Asian population, including Indonesia to which Chris refers.

This combination of clinical and economic reality does preclude any large scale case management response to early detection, which constitutes one potential branch of its expected benefit.

The other major branch of expected benefit of early detection lies in the presumed behavioral response in preventing transmission by people living with HIV. Being uninformed about this literature, I wonder if there is significant empirical evidence of the likely magnitude and epidemiological effect of this behavioral response in typical Asian, as distinct from US, settings?

I would conclude that focusing the proposed theme of the conference on early detection alone could be unduly limiting. Instead I would suggest that a broader theme highlighting the key words of "Affordability and effectiveness" would be of deeper practical relevance.


From Nicholas Bates, AFAO

Dear Clive [refers to a previous message by Clive Wing],

Your two cents worth is indeed worth a lot more. Lets hope conference organisers listen to what people such as yourself have to say. Chaing Mai was a travesty in the way that it skirted around the difficult issues. What amazes me is that no one seems to question whether such conferences are actually of any use. We continue to go to great extremes and expense to bring together people in the vague hope that somehow it will be all be better and that government, communities (both medical and non medical) will work together.

Unfortunately that is not the outcome and many people leave feeling dissillusioned. Perhaps it is time that we started to question both the purpose and format of such conferences - if we are going to bring people together then I can't see the point of giving people ten minutes to give a presentation with virtually no time for questions or discussion. We need dialogue, particularly between the different sectors, we need to get honest about what's working and what isn't and we need to overcome the domination of the bio-medical which stops these conferences from taking off and developing some sort of identity more representative of what's happening in the real world.

Surely its crazy to continue to have conferences in the developing world with such a huge focus on medical treatments when so few people will have access to those treatments. Alternative therapies and lifestyle issues must be an integral part of such conferences.

Just looking at who has been responding to the request for conference themes is interesting in itself. Unfortunately its very difficult for us westerners to shut our big mouths and keep out it but we can at least encourage the organisers to canvas widely and hope that they don't just rely on those of us who have access to the internet.

Well, just my two cents worth.


From Chris W. Green, Jakarta, Indonesia

Thanks to Prof. Frerichs for bringing up the topic of home testing kits, a subject which doesn't appear to have generated much correspondence or information, at least over the last several months. I agree that we cannot overlook the benefits of such testing methods, although as others may have noted from my earlier post, I do have concerns over the cost of treatment following diagnosis.

However, there is one major concern which we have discussed among ourselves which does not appear to have generated any wider discussion, and this is the fact that these tests use saliva and urine.

As we try to preach acceptance and support of those infected by HIV, we constantly emphasize that there is no risk of transmission from casual or social contact. Some religious leaders have tried to make mileage out of the risks of kissing and this sometimes generates undue fear, particularly among young people. We are constantly battling the fear of transmission from toilets, from swimming pools, from coughs and sneezes, from sharing eating utensils and of course from kissing. I think we are making progress with this, but we all fear that once it becomes known that the virus can be identified in saliva with what will be seen as a relatively unsophisticated test kit, the automatic assumption will be that the disease can be contracted from saliva (and urine).

As I say, I have not seen this concern addressed yet. Have I missed something? Does anyone have ideas on how we can overcome this real concern?

R.R. Frerichs Posting

In asking for potential themes for the coming AIDS meeting, Dr. Evelyn Gacad has stimulated some interesting discussion. It seems that those of us who responded most quickly, put forward themes that reflect our own views of the epidemic, including me. Being an epidemiologists, I suggested a theme that has a strong epidemiological component. Others of you who are social scientists, put forward suggestions that more broadly reflect the social and cultural dimensions of the epidemic. Subsequently, testing and the cost and consequences of testing became element of discussion, encouraged by the debate over the proposed theme. The flow of correspondences intensified, so the site editor wisely decided to summarize the various messages into a "jumbo" message, sent out on Sunday, March 31 to all.

I will be responding to several issues raised in the March 31 set of messages, but do so with some hesitation. Mr. Nicholas Bates correctly notes that our exchange of ideas has not included many health professionals from the countries of Southeast Asia. I especially likely the honesty of his pointed refrain, "Unfortunately its very difficult for us Westerners to shut our big mouths and keep out [of] it, but we can at least encourage the organizers to canvas widely and hope that they don't just rely on those of us who have access to the internet." I am sure that Dr. Gacad and her colleagues will heed his advise and "canvas widely." In the mean time, I will try to have my say one more time, and then "shut my big mouth" (or at least my email responses).

With that said, I would like to leave the theme issue (the Philippine group now has many suggestions) and respond to the messages of Nicholas Prescott of the World Bank and Chris Green of Jakarta. I had not realized that Mr. Prescott was commissioned by the Ministry of Public Health (MOPH) in Thailand to study the cost-effectiveness of the case-management decisions they would have to face if HIV was more easily detected. This is clearly an important area, and I would like very much to receive a copy of this interesting report. I was intrigued by Mr. Prescott's introductory statement that seemed to say that early detection would likely not improve the health situation in a developing country setting (or at least, the probability of doing so is "very low"). Since few developing countries have been willing to commit to early detection (other than Cuba, of course), I am not sure what was the basis for his strong statement. Perhaps he could expand on his concerns and offer some supporting documentation.

In his detailed comments, Mr. Prescott appears to focus primarily on the high cost and marginal benefits of anti-retroviral and anti-opportunistic infection drugs. He does not address the benefits of avoiding further viral transmission to spouse or offspring. Nor does he address the potential benefits to HIV infected persons of avoiding opportunistic infections that may hasten death. Both of these benefits come with early detection. For the end of 1994, GPA/WHO had estimated there were 700,000 HIV infected adults in Thailand (see UNAIDS web site for details). If these infected persons are not detected, those who are married will likely transmit the disease to their spouse and some of their children. The infectivity of the HIV subtype E appears to be much greater than subtype B which we find in the US or Europe. Thus within a few years of marriage (with 100-120 coital events per year), the virus will probably move from the infected to the susceptible spouse.

If we accept Prescott's contention that case-management is too expensive to justify early detection, then Thailand will soon face one million HIV infected persons, followed by two and three million.

There is no long-term logic in avoiding case-detection, or at least attempting case-management. Such a short-term cost-savings strategy will result in long-term misery and death, and in high medical expenses as AIDS patients continue to accumulate. Of course efficiency experts will always find ways to reduce the cost of treating AIDS patients, and possibly compromising the quality of their care. What I am suggesting is that we move beyond helping AIDS patients, and find ways to reduce the transmission of HIV so that there will be fewer with this deadly disease. My sense is that early detection is one of the few strategies that has not yet been evaluated, and one that holds considerable promise if people can be encouraged to address the problem in an open, caring, and responsible manner. If we accept the excessive worrying about the immediate expense of case-management, we will stop even the smallest demand for experimentation.

Only if we do an objective evaluation in a field setting, will we know if Mr. Prescott's concerns are valid, or if they are based on unwarranted fear and pessimism, understandably brought on by this difficult epidemic.

My final comment is directed at the question Chris W. Green raised concerning the use of saliva-based tests. He suggests that having a saliva HIV test will confuse people into believing that there is risk of transmission from casual or social contact, with saliva being the transmitting medium.

I agree that some will likely believe that this is so. They will not understand the distinction between having HIV antibodies in saliva versus having infectious HIV in saliva. But isn't this what our public health education efforts are all about? If we have a good test that is easy to use and can quickly identify those who are likely to be infected, does this not justify the extra burden of educating the public?

If the need for early detection is accepted by various governments, then public health officials have at least four educational messages that will need to be delivered. The first is that HIV is a virus that is transmitted from one person to another by intimate sexual contact, contaminated blood, or from infected mother to child (i.e., HIV is a virus). The second is that HIV infected persons should be viewed the same as persons with hypertension, diabetes, cancer, heart disease or other life-shortening conditions (i.e., HIV is a chronic disease and not a sin). The third is that HIV transmission can be stopped with simple barriers if we know who is infected (i.e., HIV is not easily transmitted). The fourth is that simple tests that look for HIV antibodies can identify who is likely to be infected (i.e., all potential or current sexual partners should be tested).

Few developing countries, other than Cuba, can afford periodic widespread testing. Thus if testing is to become common in poorer settings, the public must share in the cost, as is typically done with other products in the marketplace.

If our goal is to have people buy and conduct tests of self- and sexual-partners, we cannot impose excessive constraints on them. This is why I favor the sale of HIV indicators, or simple saliva- or fingerstick-based tests that people can buy for use in the privacy of the home, with limited government interference. I believe in three notions that others out there may support as well:

  1. people have a right to know their own health status,

  2. neither governments nor other organizations should take this right away from them with bans on home testing or other more subtle restrictions, and

  3. governments should be responsible for setting standards for HIV tests and monitoring the quality over time.

This form of responsible regulation imposes and maintains standards necessary to avoid product fraud or deceit, but does not restrict use.

If others out there agree, than it is time that we start a demonstration project to evaluate the potential benefits and harms of an early detection strategy.

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