The pathogenic fungi of the spittlebug in Mexico. III. Innocuity ofErynia neoaphidis andConidiobolus major in experimental animals

Acute oral intragastric pathogenicity and toxicity in mice of Paecilomyces fumosoroseus isolated from whiteflies

“…The liver paleness could be due to the passage of fungal clusters within hepatic sinusoids, causing temporary microemboli that occlude blood circulation. In previous reports, confirming the safety of other entomopathogenic fungi (Toriello et al 1986;Mier et al 1989Mier et al , 1994, gross pathological changes following intraperitoneal and subcutaneous inoculation were nodules, abscesses and superficial adhesions, and the histopathological study disclosed a non-specific tissue reaction to a foreign body, both in mice with viable and dead fungi. This last reaction was not observed in our study but the histological images showed fungal structures, non-germinated conidia, in the liver, spleen, kidney, brain and lungs, suggesting that the microorganism can persist in mammalian tissues but does not seem to multiply.…”

“…with other entomopathogenic fungi, Erynia neoaphidis, Conidiobolus major (Toriello et al 1986), Hirsutella thompsonii (Mier et al 1989) and Verticillium lecanii (Mier et al 1994), no fungi were recovered from any organ tissue of the tested animals. These differences in fungal recovery from the inoculated animal tissue could be due to either the thermal tolerance of P. fumosoroseus strain EH-506/3 found during the heat-killed fungus inoculum process (20 CFU after 1 h at 50°C, 13 CFU after 1 h at 55°C, and even 9 CFU after 2 h at 55°C) or to the intraspecific diversity exhibited by this fungus (Cantone and Vandenberg 1998).…”

“…Opportunistic Paecilomyces species may occur as in some fungi belonging to the entomophthoralean group. For example, E. neoaphidis and C. major, entomopathogens for aphids and spittlebugs (Samson et al 1988), are innocuous for mice and guinea pigs (Toriello et al 1986), whereas another species, Conidiobolus coronatus, is a human pathogen (Kwon-Chung and Bennet 1992). This last fungus, when inoculated in mice and guinea pigs, showed hyphae surrounded by an eosinophilic sheath in tissue organs, the Splendore-Hoeppli phenomenon (Lo´pez-Martı´nez et al 1978), similar to the same pathogenic tissue reaction found in the human mycosis, rhinoentomophthoromycosis, produced by C. coronatus (Kwon-Chung and Bennet 1992).…”