Although the
cost of Lyme disease to society and third party payers has been
evaluated (71), there has been no published evaluation of the
cost effectiveness of Lyme disease vaccination. CDC has evaluated
the cost-effectiveness of vaccination from a societal perspective
(CDC, unpublished). At an assumed cost of vaccination of $100/individual/year,
a vaccine efficacy of 0.85, a probability of 0.85 of correctly
identifying and treating early Lyme disease, and an assumed incidence
of Lyme disease of 1,000 per 100,000 persons per year, the net
cost of vaccination to society was $5,692 per case averted and
$35,375 per complicated neurologic or arthritic case avoided.
Of the variables examined, the incidence of Lyme disease had
the greatest impact on cost-effectiveness of vaccination. Under
baseline assumptions, the societal cost of vaccination exceeds
the cost of not vaccinating unless the incidence of Lyme disease
is above 1,000 per 100,000. The impact of varying assumptions
on the cost-effectiveness of vaccination is shown Figure 2. The
likelihood of early diagnosis and treatment also has a substantial
impact on vaccine cost-effectiveness because of the reduced incidence
of sequelae when patients are diagnosed and treated early in
their disease.
Most endemic
states and counties report Lyme disease incidence rates that
are well below 1,000 per 100,00 persons per year. For example,
in 1997, the highest reported state incidence rate was 70 per
100,000 in Connecticut, and the highest reported county incidence
rate was 600 per 100,000 population in Nantucket County, Massachusetts.
However, some studies suggest that only about 10-15% of physician-
diagnosed cases of Lyme disease are reported to state authorities
in highly endemic areas (45,46). Epidemiologic studies of high
risk populations in the northeastern United States have estimated
annual incidence rates above 1,000 per 100,000 in several communities
(72-75).
