Vaccination for lyme disease: Cost‐effectiveness versus cost and value

Lyme disease was first described in the US in the mid-1970s (1), although aspects of the full spectrum of Borrelia burgdorferi infection had been identified in Europe at the end of the 19th century. In the last 30 years, Lyme disease has evolved in our view (1), from an epidemiologic peculiarity (an “epidemic” of “juvenile rheumatoid arthritis”) to a unique opportunity (a specific pathogen to explain a chronic rheumatologic syndrome) and then to a public health problem (a real disease, plus the anxiety surrounding claims of “chronic Lyme disease” and “antibiotic-resistant Lyme disease”). The first step in identifying the disease was made possible by careful scientific studies (both clinical and basic research), methodical analysis, and rational thinking. The creation of a public health problem has been accelerated by misinterpretations of terminology, empirical thinking, and confusion (2). In some circles, fears of Lyme disease and of the neighboring ecologies wherein one can acquire the infection from the bite of the tick vector have become part of day-to-day existence and have strongly influenced lifestyles and daily choices. The idea of developing a vaccine for Lyme disease has also evolved (3), from an interesting scientific challenge (how does one dissect the protein repertoire of B burgdorferi, perhaps to find an Achilles heel?) to an elegant inroad (the organism down-regulates outer surface protein A [OspA] upon entering the mammalian host [4,5], but—mirable dictu—anti-OspA antibodies enter the tick and destroy the organism, where it still expresses OspA [6]) and then to a potential public health approach (can OspA vaccine prevent erythema migrans and asymptomatic seroconversion/asymptomatic infection?). The first step was driven, at least in part, by an interest in developing the first human vaccine against a spirochetal pathogen, with the implicit promise that other spirochetes, including Treponema pallidum, might be future targets. The last step has been powered, in large measure, by concerns and anxieties about the disease that often do not survive rational analysis (7–12). Vaccination has become part of a powerful armamentarium that includes many weapons to avoid Lyme disease: the use of acaricides on peridomestic property and on the people who live there, clearing out brush at the edge of one’s property that borders the forest, deer exclosure fencing, the use of deer feeders equipped with acaricide-laden brushes that treat the deer’s necks, and hunting deer to thin out the herds (13–15). The immunogenicity, safety, and efficacy of the OspA vaccine have been established in adults (16–18), and the first two of these qualities have been demonstrated in children (19,20); the vaccine has entered general use for adults, although it is not yet approved for children. Elsewhere in this issue of Arthritis & Rheumatism, Hsia et al have provided an elegant decision-analysis model that demonstrates the cost-effectiveness of the vaccine when used in the proper setting—for prevention of the disease in individuals who live in truly endemic areas (21). As noted in Table 1 of that article, the incidence of cases confirmed by the Centers for Disease Control and Prevention is highest in Nantucket County, MA (1,510 cases per 100,000, or 1.5%); the counties with the next highest incidences are Dutchess, NY; Hunterdon, NJ; Washington, RI; and Columbia, NY. These counties report annual incidences of 0.4– 0.6%. Even assuming an annual incidence of 1%, there is a cost of $9,900 per case averted; the incidence must be 10% before effectiveness and cost savings are achieved (21). The results of the study by Hsia et al confirm previous findings on the subject. Shadick et al looked at vaccine cost related to quality-adjusted life years gained, Leonard H. Sigal, MD, FACP, FACR: Lyme Disease Center, University of Medicine and Dentistry of New Jersey—Robert Wood Johnson Medical School, New Brunswick. Address correspondence and reprint requests to Leonard H. Sigal, MD, FACP, FACR, Division of Rheumatology MEB484, 1 Robert Wood Johnson Place, New Brunswick, NJ 08903-0019. E-mail: sigallh@umdnj.edu. Submitted for publication November 20, 2001; accepted in revised form January 25, 2002.