Naegleria fowleri in chick embryos. Effects of embryo age and incubation temperature, and the infectivity of embryo-derived amebae for mice.

Chick embryos were infected with Naegleria fowleri which was initially isolated from an ultimately fatal human case. Following inoculation of equivalent numbers of amebae on the chorioallantoic membrane, younger embryos died earlier than older embryos infected at the same time. Incubation of infected embryos at 32 degrees C prolonged survival only slightly in comparison with those at 37 degrees C. N. fowleri maintained for more than 25 serial passages in chick embryos retained infectivity for mice and the ability to convert to the biflagellate form in vitro.