The first entomophthoralean killing millipedes, Arthrophaga myriapodina n. gen. n. sp., causes climbing before host death.

A new species and genus of entomophthoralean fungus, Arthrophaga myriapodina kills polydesmid millipedes. This species was first seen over a century ago but never described. It is the first millipede pathogen known from the order Entomophthorales, species of which are best known as pathogens of a wide diversity of insects. The fungus induces pre-death climbing behavior in its hosts, enabling the fungus to broadcast its forcibly-discharged conidia from a high vantage, which presumably increases the fitness of the fungus. Study of herbarium specimens and photographic discoveries on the internet suggest the fungus occurs widely in eastern North America.

Mechanical Vectors Enhance Fungal Entomopathogen Reduction of the Grasshopper Pest Camnula pellucida (Orthoptera: Acrididae).

Mounting scientific evidence indicates that pathogens can regulate insect populations. However, limited dispersal and sensitivity to abiotic conditions often restricts pathogen regulation of host populations. While it is well established that arthropod biological vectors increase pathogen incidence in host populations, few studies have examined whether arthropod mechanical vectors (an organism that transmits pathogens but is not essential to the life cycle of the pathogen) influence host-pathogen dynamics. The importance of mechanical dispersal by ant scavengers, Formica fusca (L.), in a grasshopper-fungal entomopathogen system was investigated. We examined the ability of ants to mechanically disperse and transmit the pathogen, Entomophaga grylli (Fresenius) pathotype 1, to its host, the pest grasshopper Camnula pellucida (Scudder), in a series of laboratory experiments. Fungal spores were dispersed either externally on the ant's body surface or internally through fecal deposition. In addition, a third of all grasshoppers housed with fungal-inoculated ants became infected, indicating that ants can act as mechanical vectors of E. grylli. The effect of ant mechanical vectors on E. grylli incidence was also examined in a field experiment. Ant access to pathogen-exposed experimental grasshopper populations was restricted using organic ant repellent, thereby allowing us to directly compare mechanical and natural transmission. Ants increased grasshopper pathogen mortality by 58%, which led to greater pathogen reductions of grasshopper survival than natural transmission. Taken together, our results indicate that ants enhance E. grylli reduction of grasshopper pest numbers. Therefore, mechanical transmission of pathogens may be an important overlooking component of this grasshopper-fungal pathogen system.

Cutaneous fungal infection in a neonatal intensive care unit patient: a case report and literature review.

Fungal skin infections are not uncommon in healthy, premature or immunocompromised newborns. Healthy neonates usually develop fungal skin infections caused by dermatophytes, Candida and Malassezia species, whereas immunocompromised neonates are more susceptible to skin infections with opportunistic pathogens (Aspergilus, Zygomycetes). Therefore neonatal fungal skin infections can range from generally benign superficial lesions to potentially fatal, deep, necrotic forms with dissemination. We present the case of a premature neonate twin with cutaneous fungal infection in a neonatal intensive care unit. Because there were doubts concerning the correspondence of the clinical features with the cultured species in the newborn, a literature review was performed searching for similar clinical cases.

A zygomycetes-contaminated corneal graft harvested from a donor with signs of orbital trauma.

PURPOSE: To report the clinical features and histopathology of a transplanted cornea that was immediately replaced because of the possible diagnosis of lattice corneal dystrophy in the graft in which histopathologic examination revealed a Zygomycetes infection. METHODS: A 19-year-old patient with keratoconus underwent deep anterior lamellar keratoplasty (DALK) in the right eye. The operation was uneventful, transplanting a corneal graft without Descemet membrane, harvested from a donor with signs of orbital trauma. RESULTS: Three days after keratoplasty, multiple refractile lines involving the entire donor stroma were observed. With the potential diagnosis of lattice dystrophy of the donor cornea, the graft was replaced and sent for histopathologic analysis, which revealed a Zygomycetes graft infection. CONCLUSIONS: This case report introduces Zygomycetes as a cause of donor-to-host infection and also suggests that corneas harvested from donors with signs of orbital trauma may be a risk factor for donor-to-recipient transmission of such fungal infections.

Burn wounds infected by contaminated water: case reports, review of the literature and recommendations for treatment.

First-aid education for the management of burns advocates cool running water over burnt skin to limit soft tissue damage. However, the water used may itself constitute a risk. We report three cases of severe invasive and necrotizing infection in patients who used or immersed themselves in contaminated water in an attempt to extinguish the fire following acute major burns. Wound cultures from all patients yielded Aeromonas hydrophila and two yielded Bacillus cereus. One patient had a complex polymicrobial infection, including zygomycosis with Rhizomucor variabilis. All patients were treated aggressively with wound débridement, including one patient who required bilateral lower limb amputations to control progressive infection. All infections were successfully treated and all patients survived their burn injuries. We review the management of burns complicated by exposure to contaminated water leading to burn wound infections. We describe commonly reported organisms from various water sources, the appropriate initial empirical antimicrobial chemotherapy and present the clinician with a proposed algorithm for managing these serious infections.

Transmission of Pandora neoaphidis in the presence of co-occurring arthropods.

Transmission of the entomopathogenic fungus Pandora neoaphidis to the nettle aphid Microlophium carnosum was assessed in the presence of arthropods that co-exist with the fungus within the habitat but do not compete for aphid hosts. The presence of a parasitoid significantly enhanced transmission, and transmission rates were similar for both enemy and non-enemy parasitoids. Although herbivory of nettle leaves by Peacock butterfly (Inchis io) caterpillars indirectly reduced the number of M. carnosum by >30% due to a reduction in leaf area for feeding, the addition of I. io significantly increased transmission of P. neoaphidis in the remaining aphids. It is likely that enhanced transmission in the presence of A. rhopalosiphii and I. io is due to disturbance and subsequent movement of the aphid, resulting in contact with conidia deposited on the leaf surface. The presence and impact of co-occurring arthropods should be taken into consideration when assessing the transmission of fungal entomopathogens.

[Zygomycosis after hematogeneic stem cell transplantation--a current problem?]. / Zygomykosen nach Blutstammzelltransplantation--ein aktuelles Problem?

Zygomycoses are rare but often lethal mold infections predominantly affecting immunocompromised patients. Over the last years, several tertiary-care cancer centers reported an increase in the incidence of zygomycete infections in allogeneic blood stem cell transplant recipients. These observations are based on a small number of patients and should be considered in the context of a decades-long increase of mold infection rates. Diagnostic obstacles, including the difficult discrimination from the tenfold more frequent aspergilloses, may confound the reported incidences of zygomycete infections. These may be due to changes in frequency, severity and management of graft-versus-host disease promoting filamentous fungal infections, including zygomycoses. Hospitals applying long-term voriconazole prophylaxis in high-risk patients report a significant decrease in aspergillosis rates since the drug became available in 2001. The observation of increased frequencies of zygomycete infections during this period of time is not based on prospective evaluations. Therefore, the causes of these findings remain a matter of debate. Current multicenter trials on antifungal prophylaxis in high-risk patients promise to generate reliable data on the protective effect of antifungals active against molds, and the incidence of zygomycete infections in a controlled setting.

Pandora neoaphidis transmission and aphid foraging behaviour.

Pandora neoaphidis is an aphid-specific entomopathogen that produces infective conidia. As aphid movement increases, so does the likelihood of contact with conidia. Volatile distress signals released in response to aphid infestation as an indirect defence against herbivory may affect aphid foraging and, therefore, the fungus-aphid interaction. In this study, two different methods were used to investigate the effect of plant volatiles and P. neoaphidis-sporulating cadavers on (1) the colonisation of Vicia faba plants by Acyrthosiphon pisum and (2) P. neoaphidis transmission. This study indicates that A. pisum does not avoid bean plants containing P. neoaphidis and that transmission of conidia occurs during plant colonisation and, to a lesser extent, during in situ feeding. Although significantly more aphids were recovered from damaged plants compared to undamaged plants, the likelihood of infection was not affected by previous infestation by aphids.

Wide dispersal of aphid-pathogenic Entomophthorales among aphids relies upon migratory alates.

Entomophthoralean mycoses are of general importance in the natural control of aphids, but mechanisms involved in their dissemination are poorly understood. Despite several possible means of fungal survival, the dispersal of the mycoses in aphids has never been related to the flight of their migratory alates that are able to locate suitable host plants. In this study, aphid-pathogenic fungi proved to be widely disseminated among various aphids by their alates through migratory flight based on the following findings. First, up to 36.6% of the 7139 migratory alates (including nine species of vegetable or cereal aphids) trapped from air > 30 m above the ground in three provinces of China were found bearing eight species of fungal pathogens. Of those, six were aphid-specific Entomophthorales dominated in individual cases by Pandora neoaphidis, which occurs globally but has no resting spores discovered to date. Secondly, infected alates were confirmed to be able to fly for hours, to initiate colonies on plants after flight and to transmit fungal infection to their offspring in a laboratory experiment, in which 238 Sitobion avenae alates were individually flown in a computer-monitoring flight mill system after exposure to a spore shower of P. neoaphidis and then allowed to colonize host plants.

Geographical distribution and host range of entomophthorales infecting the green spruce aphid Elatobium abietinum Walker in Iceland.

Entomophthora planchoniana and Neozygites fresenii caused infection in populations of the green spruce aphid, Elatobium abietinum, in Iceland. On this aphid species En. planchoniana was exclusively found in the western part of Iceland, while N. fresenii was exclusively found in the eastern part of Iceland. This discrete and nearly nonoverlapping geographical distribution correlates with the distribution of two different populations of El. abietinum found in Iceland. On other aphid species N. fresenii, En. planchoniana, Pandora neoaphidis, and Conidiobolus obscurus were documented throughout the country. Transmission experiments showed that Pa. neoaphidis and En. planchoniana could infect the eastern population of El. abietinum, although they have never been found on this population in nature. This strongly indicates that there is little or no interaction among El. abietinum, other aphids, and their respective entomophthoralean fungi in the field. Furthermore, this study is the first to record epizootics caused by N. fresenii and En. planchoniana in the subpolar region.

Experimental exposure of Canadian toads to Basidiobolus ranarum.

Experimental transmission of the fungus Basidiobolus ranarum was induced in two treatment groups of Canadian toads (Bufo hemiophrys) and caused a fatal mycotic dermatitis. Seven of 10 (70%) toads that had their ventral skin mildly abraded and exposed to B. ranarum developed hyperemia, and sloughing of their ventral skin and died. Toads with abraded ventral skin or exposure to infected skin also were affected statistically at a higher rate than those with abraded skin and exposure to pure cultures of B. ranarum inoculated into their water source. Of toads showing clinical disease, B. ranarum was identified by both impression smears and histology in all cases, but not from toads that appeared clinically healthy. The organism was cultured from 5 of 7 (71%) toads with clinical disease but not from any toad that appeared clinically healthy (n = 28). This study documents methods of experimental transmission of B. ranarum, an organism responsible for causing a mycotic dermatitis that is fatal to toads.

Zigomicose: apresentações cutâneas e bucais / Zygomycosis: buccal and cutaneous presentations

A zigomicose é uma antes considerada rara, com tendência a aumentar, devido às condições de imunocomprometimento, em especial com o advento da Aids. Os autores apresentam revisão da literatura sobre as apresentações cutâneas e mucosas da doença. Tanto as manifestações tegumentares como bucais apresentam grande variabilidade nas lesões fundamentais. Para o diagnóstico são considerados o quadro clínico, os fatores predisponentes, a pesquisa fúngica e o exame histopatológico.