Benefit Cost Scenarios of Potential Oral Rabies Vaccination for Skunks in California

Scenario-based analyses were computed for benefits and costs linked with hypothetical oral rabies vaccination (ORV) campaigns to contain or eliminate skunk-variant rabies in skunks (Mephitis mephitis) in California, USA. Scenario 1 assumed baiting eight zones (43,388 km2 total) that comprised 73% of known skunk rabies locations in the state. Scenario 2 also assumed baiting these eight zones, but further assumed that added benefits would result from preventing the spread of skunk-variant rabies into Los Angeles County, USA. Scenarios assumed a fixed bait cost ($1.24 each) but varied campaigns (one, two and three annual ORV applications), densities of baits (37.5/km2, 75/km2 and 150/km2), levels of prevention (50%, 75%, and 100%), and contingency expenditures if rabies recurred (20%, 40%, and 60% of campaign costs). Prorating potential annual benefits during a 12-yr time horizon yielded benefit-cost ratios (BCRs) between 0.16 and 2.91 and between 0.34 and 6.35 for Scenarios 1 and 2, respectively. Economic issues relevant to potentially managing skunk-variant rabies with ORV are discussed.

Tabula rasa

English philosopher John Locke proposed that the mind of the newborn infant is a tabula rasa, or blank slate, on which experience writes. Locke was an empiricist. Development, in the empiricist view, is the product of an active environment operating on a passive mind. One alternative to empiricism is nativism. Nativists propose that the human genetic heritage includes knowledge accumulated over the course of evolution. Thus the mind of the newborn, far from being a blank slate, represents the knowledge of generations. Development, in the nativist view, is a maturational process directed by the genes. It is genes, not environments, that account for developmental change.