Trade related infections: farther, faster, quieter

Abstract

Modern global trading traffics large volumes of diverse products rapidly to a broad geographic area of the world. When emergent infections enter this system in traded products their transmission is amplified. With truly novel emergent infections with long incubation periods, such as Human Immunodeficiency Virus (HIV) or variant Creutzfeld Jacob Disease (vCJD), this transmission may silently disseminate infection to far distant populations prior to detection. We describe the chronology of two such "stealth infections," vCJD and HIV, and the production, processing, and distribution changes that coincided with their emergence. The concept of "vector products" is introduced. A brief case study of HIV incursion in Japan is presented in illustration. Careful "multisectoral" analysis of such events can suggest ecologically critical pathways of emergence for further research. Such analyses emphasize the urgency of implementing safety measures when pathogens enter globally traded products.

The Positive Feedback Advantages of Combining Buying and Investing

“…To test whether the composition of the Board could be changed significantly without a crisis-essentially, by an increase in connectivity strength alone-the program remained in the first learnt state for 500 steps and then the weighting on the connections between Club members-and only between Club members-was suddenly increased 20-fold. This resulted in a change in the composition (Figure 2) with the number of Club members on the Board increasing from 11 (6,12,22,24,30,37,40,49,59,71,85,98) to 17 (12,19,22,24,30,37,38,40,49,59,71,75,85,87,89,97,98). Importantly, this increase was achieved without a period of bad responses to the Market necessitating re-learning, that is, the composition of the Board was changed without incurring a drop in performance.…”

“…It has been noted that "streamlining of production for efficiency and cost savings may have a role in emergence of new infections when biological materials are the basis for product formulation" with the example of the manufacture of blood factor concentrates via pooling plasma from many donors such that "the entire pool could be contaminated by a single unit from an HIV-infected donor". Dr. Michael Rodell, former vice-president of the Armour Pharmaceutical Company, estimated that four infected persons could contaminate the entire world supply of factor VIII [12]. On a bigger scale, a yielding to the pressure for short-term profit was behind the pooling of animal products and their redistribution in the form of bone and marrow meal (along with changes to the rendering process); this led to the number of people potentially affected with Mad Cow Disease estimated, at one time, at several orders of magnitude [13].…”

Large multistate outbreak of norovirus gastroenteritis associated with frozen strawberries, Germany, 2012

“…This report exemplifies the risk of large outbreaks in the era of global food trade. Today, unprecedented volumes of produce (here 22 tonnes) are distributed to a large number of markets throughout the world [33], thereby increasing the risk for food safety. Public health surveillance needs to adapt to these challenges, e.g.…”