The epidemiology and transmission of AIDS: a hypothesis linking behavioural and biological determinants to time, person and place

Lessons from previous predictions of HIV/AIDS in the United States and Japan: epidemiologic models and policy formulation

This paper critically discusses two previous studies concerned with predictions of HIV/AIDS in the United States and Japan during the early 1990s. Although the study in the US applied a historical theory, assuming normal distribution for the epidemic curve, the underlying infection process was not taken into account. In the Japan case, the true HIV incidence was estimated using the coverage ratio of previously diagnosed/undiagnosed HIV infections among AIDS cases, the assumptions of which were not supported by a firm theoretical understanding. At least partly because of failure to account for underlying mechanisms of the disease and its transmission, both studies failed to yield appropriate predictions of the future AIDS incidence. Further, in the Japan case, the importance of consistent surveillance data was not sufficiently emphasized or openly discussed and, because of this, revision of the AIDS reporting system has made it difficult to determine the total number of AIDS cases and apply a backcalculation method. Other widely accepted approaches can also fail to provide perfect predictions. Nevertheless, wrong policy direction could arise if we ignore important assumptions, methods and input data required to answer specific questions. The present paper highlights the need for appropriate assessment of specific modeling purposes and explicit listing of essential information as well as possible solutions to aid relevant policy formulation.

AIDS: safety, regulation and the law in procedures using blood and blood products

The purpose of this paper is to examine issues of regulation of the market for, and use of, blood and blood products. The situation has changed since the discovery of the Human Immune Deficiency Virus (HIV), the presumed cause of AIDS, because it was recognized that some haemophiliacs were infected with HIV from transfused blood and blood products before 1985. When the danger was realized in that year, regulations were introduced internationally to prevent this, but meanwhile some haemophiliacs developed AIDS. In several countries, governments have accepted responsibility, without liability, for possible transmission of infection, and paid compensation to victims. In France three health service officials have been convicted of fraud and criminal negligence. In March 1997 a trial began in Japan of three drugs company executives accused of promoting the sale of HIV-contaminated blood products. Since then there has been a class action in the USA resulting in awards. Further issues have arisen with regard to the outcome and treatment of asymptomatic infection with HIV. The implications for public safety, and for medical and legal practice, are far reaching and reveal a need for more effective monitoring of the existing procedure for supply and clinical use of blood and blood products.

The Viral Model for AIDS: Paradigmatic Dominance, Politics, or Best Approximation of Reality?

In 1981, a non-infectious disease hypothesis was offered by the Centers for Disease Control to explain the cluster of atypical pneumonias which had appeared among gay men in the United States. Although quickly supplanted by the now widely held viral hypothesis and largely ignored by professional and media sources, that view has persisted. This article raises the question of why one explanation for the epidemic of immune system suppression has dominated the discourse on AIDS, despite the anomalies attributed to it by the proponents of other viewpoints. Alternative responses to the question are set forth drawing upon literatures in the philosophy of science and public policy formulation. Some discussion is provided of what the consequences may be if one of the contrarian hypotheses proves to be the closer approximation to the truth about AIDS etiology.