Human rabies exposures and postexposure prophylaxis in South Carolina, 1993-2002

South Carolina mandates reporting of animal bites and manages distribution of biologics for rabies postexposure prophylaxis (PEP). Incidence and epidemiologic characteristics of potential human rabies exposures and preventive treatment in South Carolina from 1993 through 2002 were examined to help assess the burden of PEP in the state and determine if the incidence of rabies exposures has changed over time.

Data on animal exposure investigations and PEP administration at the state and county level were examined, and the annual incidences of potential rabies exposures and human PEP courses were calculated.

The incidence of animal exposures for which investigations were initiated was 297.9 per 100,000 population per year, and the incidence of PEP was 10.6 per 100,000 population per year. At the county level, the incidence of PEP appeared inversely correlated with the population density. Most courses of PEP were administered following exposures to domestic species, although these animals accounted for only a small proportion of rabid animals in the state. The annual PEP incidence was similar throughout the study period, but it was markedly higher than estimates from 1981 (< 5/100,000 population per year).

The incidence of PEP in South Carolina is higher than previously thought, and these findings suggest that incidence extrapolations for other states and at the national level may be underestimated. An accurate estimation of the incidence of PEP and an understanding of rabies epidemiology is important at the state level to allow for better public health planning.