Virulence and community dynamics of fungal species with vertical and horizontal transmission on a plant with multiple infections.

The virulence evolution of multiple infections of parasites from the same species has been modeled widely in evolution theory. However, experimental studies on this topic remain scarce, particularly regarding multiple infections by different parasite species. Here, we characterized the virulence and community dynamics of fungal pathogens on the invasive plant Ageratina adenophora to verify the predictions made by the model. We observed that A. adenophora was highly susceptible to diverse foliar pathogens with mixed vertical and horizontal transmission within leaf spots. The transmission mode mainly determined the pathogen community structure at the leaf spot level. Over time, the pathogen community within a leaf spot showed decreased Shannon diversity; moreover, the vertically transmitted pathogens exhibited decreased virulence to the host A. adenophora, but the horizontally transmitted pathogens exhibited increased virulence to the host. Our results demonstrate that the predictions of classical models for the virulence evolution of multiple infections are still valid in a complex realistic environment and highlight the impact of transmission mode on disease epidemics of foliar fungal pathogens. We also propose that seedborne fungi play an important role in structuring the foliar pathogen community from multiple infections within a leaf spot.

A pseudo-outbreak of Rhinocladiella similis in a bronchoscopy unit of a tertiary care teaching hospital in London, United Kingdom.

Outbreaks of fungal infections due to emerging and rare species are increasingly reported in healthcare settings. We investigated a pseudo-outbreak of Rhinocladiella similis in a bronchoscopy unit of a tertiary care teaching hospital in London, UK. We aimed to determine route of healthcare-associated transmission and prevent additional infections. From July 2018 through February 2019, we detected a pseudo-outbreak of R. similis isolated from bronchoalveolar lavage (BAL) fluid samples collected from nine patients who had undergone bronchoscopy in a multispecialty teaching hospital, during a period of 8 months. Isolates were identified by MALDI-TOF mass spectrometry. Antifungal susceptibility testing was performed by EUCAST broth microdilution. To determine genetic relatedness among R. similis isolates, we undertook amplified fragment length polymorphism analysis. To determine the potential source of contamination, an epidemiological investigation was carried out. We reviewed patient records retrospectively and audited steps taken during bronchoscopy as well as the subsequent cleaning and decontamination procedures. Fungal cultures were performed on samples collected from bronchoscopes and automated endoscope washer-disinfector systems. No patient was found to have an infection due to R. similis either before or after bronchoscopy. One bronchoscope was identified to be used among all affected patients with positive fungal cultures. Physical damage was found in the index bronchoscope; however, no fungus was recovered after sampling of the affected scope or the rinse water of automated endoscope washer-disinfectors. Use of the scope was halted, and, during the following 12-month period, Rhinocladiella species were not isolated from any BAL specimen. All pseudo-outbreak isolates were identified as R. similis with high genetic relatedness (>90% similarity) on ALFP analysis. The study emphasises the emergence of a rare and uncommon black yeast R. similis, with reduced susceptibility to echinocandins, in a bronchoscope-related pseudo-outbreak with a potential water-related reservoir. Our findings highlight the importance of prolonged fungal culture and species-level identification of melanised yeasts isolated from bronchoscopy samples. Possibility of healthcare-associated transmission should be considered when R. similis is involved in clinical microbiology samples.

Rastreio de leveduras patogênicas isoladas de fezes de pombos no Distrito Federal-Pombos: propagadores de fungos patogênicos? / Screening for pathogenic yeasts isolated from pigeon droppings in the Federal District-Pigeons: propagators of pathogenic fungi? / Detección de levaduras patógenas aisladas de excrementos de paloma en el Distrito Federal-Palomas: ¿propagadores de hongos patógenos?

Objetivo: Investigar a presença de fungos patogênicos isolados a partir de amostras de fezes de pombos, em locais de atenção a pacientes imunocomprometidos no DF. Método: As amostras foram coletadas em hospitais onde se oferta atendimento a pacientes HIV/AIDS e que tenha uma presença massiva de pombos. Colônias de leveduras foram previamente selecionados em meio Ágar Sabouraud Dextrose acrescido de cloranfenicol, seguindo-se com análise microscópica das estruturas leveduriformes. Colônias de leveduras com suspeita de pertencerem ao gênero Candida spp. ou Cryptococcus sp., foram inoculadas no meio Ágar Cromogênico para identificação das espécies de Candida e em meio Ágar quimicamente definido para indução dos fenótipos de virulência característicos de Cryptococcus sp. Resultados: 100% das amostras analisadas apresentaram crescimento de leveduras do gênero Candida spp. e Rhodotorula sp. No meio Ágar Cromogênico foram identificadas nas amostras C. krusei em 75%; C. tropicalis em 50% e C. glabrata em 15%. Em 15% das amostras foi identificado leveduras do gênero Cryptococcus sp. Conclusão: Dados deste estudo sugerem que fezes de pombo podem estar dispersando leveduras patogênicas e contribuindo com a incidência de infecções fúngicas no DF.

Objective: To investigate the presence of pathogenic fungi isolated from pigeon stool samples, in places of care for immunocompromised patients in the Federal District. Method: The samples were collected in hospitals where care is offered to HIV / AIDS patients and which has a massive presence of pigeons. Yeast colonies were previously selected on Sabouraud Dextrose Agar plus chloramphenicol, followed by microscopic analysis of the yeast structures. Yeast colonies suspected of belonging to the genus Candida spp. or Cryptococcus sp., were inoculated in the Chromogenic Agar medium to identify Candida species and in chemically defined Agar medium to induce the virulence phenotypes characteristic of Cryptococcus sp. Results: 100% of the analyzed samples showed growth of yeasts of the genus Candida spp. and Rhodotorula sp. In the chromogenic agar medium, 75% were identified in C. krusei samples; C. tropicalis in 50% and C. glabrata in 15%. In 15% of the samples, yeasts of the genus Cryptococcus sp. Conclusion: Data from this study suggest that pigeon feces may be dispersing pathogenic yeasts and contributing to the incidence of fungal infections in DF

Objetivo: Investigar la presencia de hongos patógenos aislados de muestras de heces de palomas, en los lugares de atención a pacientes inmunodeprimidos del Distrito Federal. Método: Las muestras se recolectaron en hospitales donde se brinda atención a pacientes con VIH / SIDA y que tiene una presencia masiva de palomas. Las colonias de levadura se seleccionaron previamente en Sabouraud Dextrose Agar más cloranfenicol, seguido de un análisis microscópico de las estructuras de la levadura. Las colonias de levaduras sospechosas de pertenecer al género Candida spp. o Cryptococcus sp., se inocularon en medio de agar cromogénico para identificar especies de Candida y en medio de agar químicamente definido para inducir los fenotipos de virulencia característicos de Cryptococcus sp. Resultados: el 100% de las muestras analizadas presentó crecimiento de levaduras del género Candida spp. y Rhodotorula sp. En el medio agar cromogénico, el 75% se identificó en muestras de C. krusei; C. tropicalis en 50% y C. glabrata en 15%. En el 15% de las muestras, levaduras del género Cryptococcus sp. Conclusión: Los datos de este estudio sugieren que las heces de las palomas pueden estar dispersando levaduras patógenas y contribuyendo a la incidencia de infecciones fúngicas en el DF.

Talaromycosis (Penicilliosis) Due to Talaromyces (Penicillium) marneffei: Insights into the Clinical Trends of a Major Fungal Disease 60 Years After the Discovery of the Pathogen.

Talaromycosis (penicilliosis) is a major fungal disease endemic across a narrow band of tropical countries of South and Southeast Asia. The etiologic agent is a thermally dimorphic fungus Talaromyces (Penicillium) marneffei, which was first isolated from a bamboo rat in Vietnam in 1956, but no formal description was published. In 1959, Professor Gabriel Segretain formally described it as a novel species Talaromyces (Penicillium) marneffei, and the human pathogenic potential of the fungus in Mycopathologia. The first natural human case of talaromycosis (penicillosis) was reported in 1973 and involved an American minister with Hodgkin's disease who lived in Southeast Asia. Sixty years after the discovery of the pathogen, talaromycosis caused by T. marneffei is recognized as an important human disease with the potential to cause high mortality in the absence of proper diagnosis and prompt treatment. Talaromycosis remains a significant infectious complication in HIV/AIDS patients and in patients with other immune defects. The disease is being recognized with an increasing frequency well beyond the traditional endemic areas. The natural reservoirs of T. marneffei in wild rodents are well-defined, which links the ecology with the epidemiology of talaromycosis in endemic areas. There is an urgent unmet need for rapid and affordable point-of-care diagnostic tests. We also need more clinical studies to define the best therapeutic options for the management of talaromycosis patients.

Sclerotinia minor Endornavirus 1, a Novel Pathogenicity Debilitation-Associated Mycovirus with a Wide Spectrum of Horizontal Transmissibility.

Sclerotinia minor is a phytopathogenic fungus causing sclerotinia blight on many economically important crops. Here, we have characterized the biological and molecular properties of a novel endornavirus, Sclerotinia minor endornavirus 1 (SmEV1), isolated from the hypovirulent strain LC22 of S. minor. The genome of SmEV1 is 12,626 bp long with a single, large open reading frame (ORF), coding for a putative protein of 4020 amino acids. The putative protein contains cysteine-rich region (CRR), viral methyltransferase (MTR), putative DEXDc, viral helicase (Hel), and RNA-dependent RNA polymerase (RdRp) domains. The putative protein and the conserved domains are phylogenetically related to endornaviruses. SmEV1 does not contain a site-specific nick characteristic of most previously described endornaviruses. Hypovirulence and associated traits of strain LC22 and SmEV1 were readily cotransmitted horizontally via hyphal contact to isolates of different vegetative compatibility groups of S. minor. Additionally, SmEV1 in strain LC22 was found capable of being transmitted vertically through sclerotia. Furthermore, mycelium fragments of hypovirulent strain LC22 have a protective activity against attack by S. minor. Taken together, we concluded that SmEV1 is a novel hypovirulence-associated mycovirus with a wide spectrum of transmissibility, and has potential for biological control (virocontrol) of diseases caused by S. minor.

Imported endemic mycoses in Spain: Evolution of hospitalized cases, clinical characteristics and correlation with migratory movements, 1997-2014.

Endemic mycoses are systemic fungal infections. Histoplasmosis is endemic in all temperate areas of the world; coccidioidomycosis and paracoccidioidomycosis are only present in the American continent. These pathogens are not present in Spain, but in the last years there has been an increase of reported cases due to migration and temporary movements. We obtained from the Spanish hospitals records clinical and demographic data of all hospitalized cases between 1997 and 2014. There were 286 cases of histoplasmosis, 94 of Coccidioidomycosis and 25 of paracoccidioidomycosis. Overall, histoplasmosis was strongly related to HIV infection, as well as with greater morbidity and mortality. For the other mycoses, we did not find any immunosuppressive condition in most of the cases. Although we were not able to obtain data about clinical presentation of all the cases, the most frequently found was pulmonary involvement. We also found a temporal correlation between the Spanish population born in endemic countries and the number of hospitalized cases along this period. This study reflects the importance of imported diseases in non-endemic countries due to migratory movements.

Contamination of cockroaches (Insecta: Blattaria) to medically fungi: A systematic review and meta-analysis.

INTRODUCTION: Fungal infections have emerged worldwide. Cockroaches have been proved vectors of medically fungi. METHODS: A systematic meta-analysis review about cockroach fungal contamination was investigated. Relevant topics were collected between January 2016 and January 2017. After a preliminary review among 392 collected papers, 156 were selected to become part of the detailed systematic meta-analysis review. RESULTS: Cockroaches contaminated to 38 fungi species belonging to 19 families and 12 orders. About 38, 25 and 13 fungal species were recovered from the American, German and brown-banded cockroaches, respectively with a variety of medical importance. Except the fungi isolated from German and brown-banded cockroaches, 15 species have been isolated only from the American cockroaches. The global world mean and trend of cockroach fungal contamination were 84.1 and 50.6-100%, respectively in the human dwelling environments. There is a significant difference between cockroach fungal contamination in the urban and rural environments (P<0.05) without a significant difference between hospital and household environments (P>0.05). The external and internal cockroach fungal contamination is more dangerous than entire surfaces, while the internal is more dangerous than the external surface. The German and brown-banded cockroach fungal contamination are more dangerous than the American cockroaches in the hospital environments. CONCLUSION: The study indicates that globally cockroach fungal contamination has been increased recognizing as agents of human infections and associating with high morbidity and mortality in immune-compromised patients. These facts, along with insecticide resistance emergence and increasing globally cockroach infestation, reveal importance of cockroaches and need for their control more than ever.

[The Importance of Vector Management for Prevention of Hospital Infections]. / Hastane Infeksiyonlarinin Önlenmesinde Vektör Mücadelesinin Önemi.

Many researches show that cockroaches, ants, some other arthropods and also rodents in hospitals, can act as potential vectors of medically important bacteria, fungi and parasites. The results of microbiological studies show that these animals play a significant role in the epidemiology of hospital infections. These vectors may be found inside of the kitchens, patient rooms, toilets, medicine stores, canteen and wards in health care environments. The importance of vector control in order to prevent the spread of nosocomial infections in healthcare facilities was discussed in this paper. This study also gives information on integrated control methods for vectors in hospitals.

Temporal distribution of tuberculosis in the State of Amazonas, Brazil

Tuberculosis (TB) is one of the infectious diseases that contributes most to the morbidity and mortality of millions of people worldwide. Brazil is one of 22 countries that accounts for 80% of the tuberculosis global burden. The highest incidence rates in Brazil occur in the States of Amazonas and Rio de Janeiro. The aim of this study was to describe the temporal distribution of TB in the State of Amazonas. Between 2001 and 2011, 28,198 cases of tuberculosis were reported in Amazonas, distributed among 62 municipalities, with the capital Manaus reporting the highest (68.7%) concentration of cases. Tuberculosis was more prevalent among males (59.3%) aged 15 to 34 years old (45.5%), whose race/color was predominantly pardo (64.7%) and who had pulmonary TB (84.3%). During this period, 81 cases of multidrug-resistant TB were registered, of which the highest concentration was reported from 2008 onward (p = 0.002). The municipalities with the largest numbers of indigenous individuals affected were São Gabriel da Cachoeira (93%), Itamarati (78.1%), and Santa Isabel do Rio Negro (70.1%). The future outlook for this region includes strengthening the TB control at the primary care level, by expanding diagnostic capabilities, access to treatment, research projects developed in collaboration with the Dr. Heitor Vieira Dourado Tropical Medicine Foundation .;Fundação de Medicina Tropical Dr. Heitor Vieira Dourado (FMT-HVD).; and financing institutions, such as the project for the expansion of the Clinical Research Center and the creation of a hospital ward for individuals with transmissible respiratory diseases, including TB.

Fatal Scopulariopsis infection in a lung transplant recipient: lessons of organ procurement.

Seventeen days after double lung transplantation, a 56-year-old patient with idiopathic pulmonary fibrosis developed respiratory distress. Imaging revealed bilateral pulmonary infiltrates with pleural effusions and physical examination demonstrated sternal instability. Broad-spectrum antibacterial and antifungal therapy was initiated and bilateral thoracotomy tubes were placed. Both right and left pleural cultures grew a mold subsequently identified as Scopulariopsis brumptii. The patient underwent pleural irrigation and sternal debridement three times but pleural and wound cultures continued to grow S. brumptii. Despite treatment with five antifungal agents, the patient succumbed to his illness 67 days after transplantation. Autopsy confirmed the presence of markedly invasive fungal disease and pleural rind formation. The patient's organ donor had received bilateral thoracostomy tubes during resuscitation in a wilderness location. There were no visible pleural abnormalities at the time of transplantation. However, the patient's clinical course and the location of the infection, in addition to the lack of similar infection in other organ recipients, strongly suggest that Scopulariopsis was introduced into the pleural space during prehospital placement of thoracostomy tubes. This case of lethal infection transmitted through transplantation highlights the unique risk of using organs from donors who are resuscitated in an outdoor location.

Aerially transmitted human fungal pathogens: what can we learn from metagenomics and comparative genomics?

In the last few decades, aerially transmitted human fungal pathogens have been increasingly recognized to impact the clinical course of chronic pulmonary diseases, such as asthma, cystic fibrosis or chronic obstructive pulmonary disease. Thanks to recent development of culture-free high-throughput sequencing methods, the metagenomic approaches are now appropriate to detect, identify and even quantify prokaryotic or eukaryotic microorganism communities inhabiting human respiratory tract and to access the complexity of even low-burden microbe communities that are likely to play a role in chronic pulmonary diseases. In this review, we explore how metagenomics and comparative genomics studies can alleviate fungal culture bottlenecks, improve our knowledge about fungal biology, lift the veil on cross-talks between host lung and fungal microbiota, and gain insights into the pathogenic impact of these aerially transmitted fungi that affect human beings. We reviewed metagenomic studies and comparative genomic analyses of carefully chosen microorganisms, and confirmed the usefulness of such approaches to better delineate biology and pathogenesis of aerially transmitted human fungal pathogens. Efforts to generate and efficiently analyze the enormous amount of data produced by such novel approaches have to be pursued, and will potentially provide the patients suffering from chronic pulmonary diseases with a better management. This manuscript is part of the series of works presented at the "V International Workshop: Molecular genetic approaches to the study of human pathogenic fungi" (Oaxaca, Mexico, 2012).

Current problems concerning parasitology and mycology with regard to diseases of the skin and its appendages.

Current issues concerning Parasitology and Mycology with regard to diseases of the skin and its appendages are presented. Aspects of diagnostics, clinical picture and therapy of skin and nail mycoses, as well as difficulties in the diagnosis and treatment of both native parasitoses (toxoplasmosis) and imported human tropical parasitoses (malaria, filariosis) have been emphasised. The clinical importance of environmental mould fungi in nosocomial infections and fungal meningitis, as well as selected properties of fungi isolated from patients with head and neck neoplasms treated by radiotherapy are discussed. Other mycological topics include the characteristics of newly-synthesized thiosemicarbazides and thiadiazoles as potential drugs against toxoplasmosis and their biological activity against Toxoplasma gondii tachyzoites, selected molecular mechanisms of resistance to azoles, Candida albicans strains and a new tool (barcoding DNA) for describing the biodiversity of potential allergenic molds. The importance of environmental factors in pathogenesis of mycoses and parasitoses is noted. The characteristics of pathogenic fungi isolated from natural ponds in Bialystok and potentially pathogenic yeast-like fungi isolated from children's recreation areas in Lodz are presented. The ongoing problem of anthropozoonoses is considered, as are the roles of stray cats and dogs in contaminating soil with the developing forms of intestinal parasites. The characteristics of the human microbiome, including population composition, activity and their importance in normal human physiology, are presented, as are the major goals of the Human Microbiome Project initiated by National Institutes of Health (NIH).

[Frequency of polyphasic health-care-associated outbreaks is highest in surgical departments - results of a systematic literature search]. / Chirurgen sind am häufigsten von mehrphasischen nosokomialen Ausbrüchen betroffen - Ergebnisse einer systematischen Literaturrecherche.

BACKGROUND: So-called polyphasic nosocomial outbreaks describe a situation in which additional infections occur after a certain case-free interval - despite the detection of the outbreak's source. This article summarises the results of a systematic search of the medical literature on polyphasic outbreaks. MATERIALS AND METHODS: For this purpose, the Outbreak Worldwide-Database, PubMed and reference lists of relevant articles were screened. RESULTS: A total of 124 polyphasic outbreaks (median duration of 50 weeks) was included in the analysis and then compared to 2089 monophasic nosocomial outbreaks. Surgical departments were significantly more often involved in polyphasic outbreaks than they were in monophasic events (33.9 % vs. 24.5 %; p < 0.05). Hepatitis B virus outbreaks were significantly more often seen as poly-phasic events. Either there had been more than one source initially, or a new source developed during the first phase of the outbreak and led to additional cases thereafter. CONCLUSIONS: Up to now, only little is known about polyphasic nosocomial outbreaks. Thus, there is a further need to close this gap of information in the future. Personnel on the ward as well as -infection control staff should always consider the possibility of the existence of more than one -source when investigating a nosocomial outbreak.

Trichosporon asahii as a prospective pathogen in solid organ transplant recipients.

Trichosporon spp. is not an important factor of mycotic infections in immunocompetent patients. It may be a cause of invasive mycoses with a high mortality rate in patients undergoing solid organ transplantation. We have analysed the antifungal agents' susceptibility of Trichosporon asahii and its frequency of occurrence as a prospective etiological agent of infections in liver, kidney and simultaneous pancreas-kidney transplant recipients. Clinical specimens (urine, blood, peritoneal fluid and swabs) were obtained from patients hospitalised in the Institute of Transplantation Medicine, Department of General and Transplantation Surgery, Medical University of Warsaw in 2005 and 2006. Microbiological tests were performed in Mycological Laboratory, Department of Microbiology, Medical University of Warsaw. A total of 475 strains of yeast-like fungi were isolated from clinical specimens taken from 263 liver, kidney and simultaneous pancreas-kidney transplant recipients and from 26 organ donors. Trichosporon asahii was found in 26 clinical samples taken from 18 patients and one organ donor. Positive cultures were obtained from 22 urine samples, one stoma fluid, one wound swab, one tracheal aspirate and one ejaculate. Isolates of Trichosporon asahii were found in 6% of total positive mycological cultures in the solid organ transplant recipients. Among cultured strains, 11 isolates were resistant to fluconazole, four to itraconazole and three of them demonstrated resistance to amphotericin B.

[Animals as a potential source of human fungal infections]. / Zwierzeta jako potencjalne zródlo zakazen grzybiczych u ludzi.

Changing environment is a reason, that many saprotrophic fungi became opportunists and in the end also maybe a pathogenic. Host specific adaptation is not so strong among fungi, so there are many common fungal pathogens for people and for animals. Animals suffering from dermatomycosis are well recognize as source of human superficial mycoses. Breeding of different exotic animals such as parrots, various Reptiles and Amphibians, miniature Rodents and keeping them as a pets in the peoples houses, have become more and more popular in the recent years. This article is shortly presenting which animals maybe a potential source of fungal infections for humans. Looking for the other mycoses as systemic mycoses, especially candidiasis or aspergilosis there are no data, which allow excluding sick animals as a source of infection for human, even if those deep mycoses have endogenic reactivation mechanism. Immunocompromised people are in high-risk group when they take care of animals. Another important source of potentially pathogenic, mostly air-born fungi may be animal use in experimental laboratory work. During the experiments is possible that laboratory workers maybe hurt and these animals and their environment, food and house boxes could be the possible source of microorganisms, pathogenic for humans or other animals. Unusual way to inoculate these potentially pathogens into the skin of laboratory personnel may cause granulomatous, local lesions on their hands.

Candidemia en niños y factores de riesgo asociados / Candidemia in children and associate factors of risk

Cada vez es más frecuente la adquisición de infecciones fúngicas intrahospitalarias, generando una mayor morbilidad y mortalidad, sobre todo en pacientes que presentan factores de riesgo. Determinar la prevalencia, en los pacientes hospitalizados en el Hospital de Niños "JM de Los Ríos" (Caracas-Venezuela), de infecciones sistémicas ocasionadas por las distintas especies de Candida en el período 2002-2006. Estudio retrospectivo, transversal, descriptivo y no experimental. Se ubicaron las historias clínicas de estos pacientes y se recopilaron de un formato los siguientes datos: edad, sexo, servicio de hospitalización, diagnóstico de egreso, factores de riesgo relacionados con la infección. Se utilizó como prueba de análisis estadístico medidas de tendencia central. Se logró el aislamiento de microorganismos en un 21,68 por ciento (7,14 por ciento correspondieron a cepas de Candida). El sexo masculino predominó con un 58,61 por ciento, los lactantes fueron el grupo más afectado con un 38,14 por ciento. El uso de antibióticos de amplio espectro predominó entre los factores de riesgo. El 71,16 por ciento de los aislamientos correspondieron a cepas del grupo de Candida no albicans, representando las especies de Candida parapsilosis y Candida tropicalis casi las dos terceras partes de los aislamientos y asociándose con mayor frecuencia al uso de catéteres venosos centrales. El 75 por ciento de las cepas de Candida aisladas en hemocultivo han sido reportadas como sensibles a fluconazol y anfotericina B por la literatura médica mundial.

Epidemiology of neonatal infections.

The World Health Organization estimates that more than 4 million neonates die each year and 98% of these deaths occur in developing countries. Infections are among the main causes of neonatal mortality. The neonatal health is intrinsically linked to the mother's health and the care she receives before, during and immediately after delivery. If in resource-rich countries improvements in perinatal conditions, prevention and management of fetal-neonatal infections have reduced the burden of neonatal morbidity and mortality, in resource-limited areas they have only just improved and many barriers remain still to be overcome. Prematurity is often due to fetal infections and represents a significant risk factor for nosocomial infections.

Virulence, horizontal transmission, and sublethal reproductive effects of Metarhizium anisopliae (Anamorphic fungi) on the German cockroach (Blattodea: Blattellidae).

Virulence of Metarhizium anisopliae (Metschnikoff) Sorokin strain EAMa 01/121-Su against the German Cockroach, Blatella germanica (L.), was determined using four concentrations ranging from 4.2 x 10(6) to 4.2 x 10(9) spores per milliliter. The LD50 value was 1.4 x 10(7) spores per milliliter (56,000 spores per cockroach) and LT50 values were 14.8 days and 5.3 days for 4.2 x 10(8) and 4.2 x 10(9) spores per milliliter, respectively. An experiment was conducted to evaluate whether a fungal transmission could exist among infected and healthy cockroaches. Percentage mortality at a ratio of 1:10 of infected to unexposed cockroaches was 87.5% and LT50 was 12.2 days, which indicated the potential of this strain to be horizontally transmitted and to rapidly spread the infection in the insect population. The effect of a sublethal dose (ca. LD60) of M. anisopliae EAMa 01/121-Su strain, applied topically on German cockroaches, was studied by reciprocal crossing. Othecal production, oothecal hatchability, and nymphal production declined upon exposure to M. anisopliae EAMa 01/121-Su strain. The mean number of oothecae laid by female was progressively and significantly reduced by fungal treatment from second oviposition period onwards. Oothecal hatch of fungally challenged females was reduced by 46-49%, oothecal viability by 48-85%, and nymphal production by 22-35%. Only treated females showed an effect on oothecal production, oothecal hatch, and nymphal production, although oothecal hatch was also governed by treated males at a higher significance level. Our results on virulence and horizontal transmission of fungal conidia of M. anisopliae EAMa 01/121-Su strain and its sublethal reproductive effects on German cockroach females are discussed in terms of its potential to decrease the pest status of B. germanica in the short and long terms.