| digenetic trematodes, acanthatrium sp. and lecithodendrium sp., as vectors of neorickettsia risticii, the agent of potomac horse fever. | neorickettsia (formerly ehrlichia) risticii, the agent of potomac horse fever (phf), has been recently detected in trematode stages found in the secretions of freshwater snails and in aquatic insects. insectivores, such as bats and birds, may serve as the definitive host of the trematode vector. to determine the definitive helminth vector, five bats (myotis yumanensis) and three swallows (hirundo rustica, tachycineta bicolor) were collected from a phf endemic location in northern california. bat ... | 2003 | 14627451 |