The daily emergence of the cercaria of Schistosoma mansoni
Maldonado, J.F.
Boletin de la Asociacion Medica de Puerto Rico 51: 336-339
1959
ISSN/ISBN: 0004-4849 PMID: 14420251 Document Number: 700067
Using a technique for the recovery of cercariae from large volumes of water essentially that described by Rowan Maldonado found that in a concrete pond in the Rio Piedras area of San Juan, Puerto Rico, Schistosoma mansoni cercariae emerged from Australorbis glabratus during the daytime and accumulated until approximately 6.00 p.m., after which time the numbers decreased. Light intensity did not appear to affect cercarial emergence. Each snail shed approximately 500 cercariae per day. The life-span of cercariae, calculated to be about ten hours, appeared to be shortened with increase in water temperature. J.w.s.