Volume 3, Number 2—June 1997 Seroepidemiologic Studies of
Hantavirus Infection Among Wild Rodents in California A total of
4,626 mammals were serologically tested for antibodies to Sin
Nombre virus. All nonrodent species were antibody negative.
Among wild rodents, antibody prevalence was 8.5% in murids, 1.4%
in heteromyids, and < 0.1% in sciurids. Of 1,921 Peromyscus
maniculatus (deer mice), 226 (11.8%) were antibody positive,
including one collected in 1975. The highest antibody prevalence
(71.4% of 35) was found among P. maniculatus on Santa Cruz
Island, off the southern California coast. Prevalence of
antibodies among deer mice trapped near sites of human cases
(26.8% of 164) was significantly higher than that of mice from
other sites (odds ratio = 4.5; 95% confidence interval = 1.7,
11.6). Antibody prevalence increased with rising elevation
(>1,200 meters) and correlated with a spatial cluster of
hantavirus pulmonary syndrome cases in the Sierra Nevada. In
spring 1993, a cluster of unexplained severe acut