Your mileage may vary

I t was 1973. Because of an OPEC oil embargo, there were long lines surrounding gas stations. Over a few years, people became increasingly interested in the gas efficiencies of their vehicles. The US government began publishing information about the fuel economy of cars and trucks. These published fuel economy ratings were based on a computer program that simulated “typical” driving conditions in cities and on highways and, with measurement of wheel rotation to determine distance and the presence of carbon in engine exhausts as a means to measure fuel consumption, the government estimated the fuel economy of each vehicle. With the public increasingly focused on gas consumption, these numbers became integral parts of advertising by car and truck manufacturers. A problem with these numbers was soon identified, with the numbers found to be inaccurate for a variety of reasons, including the realization that the computer-based driving simulation did not reflect the real driving habits of the public, who accelerated and decelerated much more quickly than those in the simulation. The true fuel economy numbers actually measured by the public were much less than the government estimates. To protect themselves from lawsuits, legal departments of car and truck manufacturers began to issue disclaimers in their advertisements that warned the customer that their fuel economy may differ from the published estimated fuel economy ratings. In this issue, McCullough and colleagues from five university hospitals and Cerus Corporation report the results of a study investigating costs that might be affected with universal adoption of pathogen reduction for apheresis platelets (PLTs) using amotosalen and UV light. The bottom line of their analysis appears in the abstract and concludes that adoption of pathogen reduction may result in a total potential cost savings of $141.65/unit. While an analysis to estimate the total value of pathogen reduction is certainly useful and timely, some may question several of the underlying assumptions of the analysis and whether each of the identified cost savings can be realistically and universally applied to all units. The authors used relevant information from their institutions to determine staff costs, equipment costs, reagent costs, and patient costs, to estimate the total costs of current tests (West Nile virus, syphilis, cytomegalovirus [CMV]) that could be eliminated with the implementation of pathogen reduction. Their cost of infectious disease testing, however, is calculated on a per-unit basis despite the fact that samples for infectious disease testing are taken before splitting of an apheresis collection into double and triple units. Thus in their analysis, there is a doubling and tripling of the actual costs incurred for West Nile virus, syphilis, CMV, automated blood culture, Babesia, and dengue testing from double and triple units, respectively. The reduction of testing costs by sampling apheresis collections rather than units is significant. In the United States, approximately 1.9 apheresis PLT units are manufactured from each collection. Curiously, the authors do not fail to recognize the savings that are generated on the cost of amotosalen bag sets for apheresis collections that are split into double units. While West Nile virus and syphilis tests are performed on every unit, CMV testing is performed based on the practice of the physician or hospital; some leukoreduced units are transfused without testing because, depending on a patient’s medical status, CMV risk reduction obtained by leukoreduction alone may be considered adequate. The authors performed their calculations assuming that all blood is universally CMV tested. Therefore, the actual savings from not performing CMV testing because of pathogen reduction will likely be less among practices solely relying on leukoreduction for CMV mitigation than those reported by the authors. Babesia testing costs were determined by cost recovery charges for current investigational new drug testing in New England and the upper Midwest. Current thinking is that a regional approach to testing will be proposed. If a regional approach is eventually adopted, it is possible that actual savings from Babesia testing by implementing pathogen reduction in nonendemic states may be considerably less than those proposed by the authors. Dengue, while endemic in Puerto Rico, has not yet widely spread to the continental United States. The authors correctly point out that isolated autochthonous outbreaks have occurred in southern Florida, Texas, and Hawaii. While it would be prudent to implement dengue testing in the continental United States should the disease become more frequent in the mainland, the mosquito vectors of dengue, Aedes aegypti and Ae. albopictus, currently have a range predominantly in the Eastern sector of the United States and limited areas of the Southwest. If dengue becomes more common in the continental United States, it is possible that a regional testing approach would again be adopted and doi:10.1111/trf.13226