Serum samples from 15 species of rodents and 33 species of birds were tested for agglutinins against Coxiella burnetii by the microagglutination test. Of 759 rodents tested, 21 (3%) were seropositive. Antibody positive rodents included muskrats, Ondatra zebethica, (11%), Rattus spp. (10%), Beechey ground squirrels, Otospermophilus beecheyi, (6%), wood rats, Neotoma fuscipes, (5%), and Peromyscus spp. (2%). Of 583 birds tested, 118 (20%) were seropositive. This included white crowned sparrows, Zonotrichia leucophrys, gold crowned sparrows, Z. atricapilla, and English sparrows, Passer domesticus, (68% in the composite); coots, Fulica americana, (29%); blackbirds, Euphagus cyanocephalus, (33%); crows, Corvus brachyrhyncos, (29%); robins, Turdus migratorius, (16%); pigeons, Columba fasciata, (10%); and mallard ducks, Anas platyrhynchos, (7%). There was a tendency for the seropositive animals to have been collected in the vicinity of endemically infected livestock.
From the Department of Epidemiology and Preventive Medicine, School of Veterinary Medicine, University of California, Davis, California 95616, USA.
Department of Community Health, School of Medicine, University of California, Davis.
Institute of Ecology, University of California, Davis.
Wildlife and Fisheries Biology, University of California, Davis.