Dr. Edward H. Kaplan, a management scientist with the Yale University School of Management, presents a paper with his findings at an international convention of the Institute for Operations Research and the Management Scientists (INFORMS) and the Operational Research Society of Israel (ORSIS) at Tel Aviv University on Monday, June 29 from 1 to 2 PM. He will present his findings again the same week at the 12th World AIDS conference in Geneva. He is the author of articles on this topic that have appeared in the British medical journal The Lancet and OR/MS Today, a publication of INFORMS.
Risk is one infection in 10 years
Dr. Kaplan uses mathematical modeling employed by operations researchers and management scientists to show that the actual risk of HIV infection in blood accepted from Ethiopian immigrants to Israel is only a single instance in 10 years.
Those who supported the ban — which has since been modified — note that the AIDS infection rate among Ethiopian immigrants is 50 times that of the rest of the Israeli population. Americans are roughly 25 times more likely to be infected with HIV than Israelis.
False Negatives
These statistics, he says, don’t tell an accurate story. In his research, Dr. Kaplan examines the question of whether Israel's Ethiopian blood ban was justified from a cost/benefit perspective.
Since all blood donations in Israel are screened for the presence of HIV antibody, blood is only accepted from donors who test HIV negative. Thus, the number of infectious donations prevented by the ban equals the number of donations from infected Ethiopian donors that tested antibody negative. At issue are false negatives, which occur in newly infected individuals.
While false negative tests can and do occur, the fraction of all antibody negative donations that are actually infectious is small. In the case of donations from Ethiopian immigrants to Israel, the rate of new infections has been estimated as at most 2.9 infections per 1,000 uninfected persons per year. Roughly one infectious donation would occur in every 5,000 antibody negative donations accepted.
According to the Navon Commission, which was formed to deal with issues raised by the blood ban, Ethiopian donors averaged only 485 donations annually. An estimated 1.3% of such donors test positive for HIV antibody, enabling roughly 480 antibody negative donations from Ethiopian immigrants per year. Of 480 antibody negative donations annually, one in every 5,000 would be infectious, implying that only 0.1 infectious donations were prevented each year, or equivalently one infectious donation every 10 years, not a major public health achievement, says Dr. Kaplan.
A similar analysis for non-Ethiopian Israelis reveals that of 221,960 antibody negative donations per year, 1.1 in one million would be expected to be infectious, for an infectious donation rate of 0.24 infectious donations per year, or roughly one every four years.
Those favoring exclusion argued that since Ethiopian donors exhibit a much greater HIV risk on a per donor basis, the exclusion decision was correct. Dr. Kaplan argues that given thepercentage of Ethiopian donations — only 480 compared to 221,960 — accepting a donation from an Ethiopian is beside the point. What is required is a willingness to accept blood from a supply of antibody negative donations, of which only 0.2% come from Ethiopian immigrants.
Therefore, the benefits of the ban, Dr. Kaplan says, can be viewed as preventing at most 0.1 infectious donations a year. The costs, he argues, were much higher, considering the damage done to relations with the Israeli Ethiopian community and a drop in blood supply coupled with protests that led to 70 injuries after the ban became known.
Of greater importance, Dr. Kaplan laments, is a lost opportunity to check the infection of AIDS: If Israeli officials working in Ethiopia with Jews preparing to immigrate had educated them about the spread of HIV, he believes, much heartbreak could have been averted.
Invisible but Essential
Operations researchers —also known as management scientists — are little known but indispensable experts who use math and science to better decision-making, management, and operations. Operations research practitioners work at Tel Aviv University, IBM, the military, and throughout business, government, and academia. Impressively, they make sense of millions of details. For example, operations research is responsible for the math models used to book the complex web of passenger reservations and discount tickets at busy airlines.
The theme of the conference is "Management Science and Operations Research in an Emerging Region." The convention will include sessions on topics applied to a wide number of fields, including information technology, health care, the Internet, energy, marketing, real estate, securities, and telecommunications. Nearly 700 papers are scheduled to be presented at the four-day conference. The General Co-Chairs of the convention are Professor Jacob Hornik of Tel Aviv University and Professor Benjamin Lev of the University of Michigan - Dearborn. Additional information is online at http://www2.informs.org/Conf/TelAviv98/.
The Institute for Operations Research and the Management Sciences (INFORMS) is an international scientific society with 12,000 members, including Nobel Prize laureates, dedicated to applying scientific methods to help improve decision-making, management, and operations. Members of INFORMS work primarily in business, government, and academia. They are represented in fields as diverse as airlines, health care, law enforcement, the military, the stock market, and telecommunications.
The Operational Research Society of Israel (ORSIS) was founded in 1966 to promote and enhance the research and practice of operations research in Israel. It publishes a biannual newsletter and holds a national conference every year at a chosen location in Israel. Of the 300 members, one third are academics and the rest are in industry, business, and the public sector.