Maggot Extract Interrupts Bacterial Biofilm Formation and Maturation in Combination with Antibiotics by Reducing the Expression of Virulence Genes.

Biofilms are aggregates of bacteria encased in an extracellular polymer matrix that acts as a diffusion barrier protecting the microbial community. Bacterial communication occurs by small signaling molecules called quorum sensing (QS) factors, which are involved in the activation of virulence genes and formation of biofilms. Larvae of the green bottle blowfly Lucilia sericata remove necrotic tissue by mechanical action (debridement) and proteolytic digestion. We produced a freeze-dried storable powder from larval extract and investigated its therapeutic effect on biofilms. Larval extract in concentrations of 6 and 12 mg/mL in combination with 0.5% antibiotics (≙50 U/mL penicillin and 50 µg/mL streptomycin) diminished free-floating (planktonic) Pseudomonas aeruginosa maintenance, while it showed no effect on Staphylococcus aureus and was not toxic to dermal cells. We established an ex vivo human dermal wound model. Larval extract in concentrations of 24 and 75 mg/mL in the presence of antibiotics (0.5%) significantly destroyed the biofilm stability of both P. aeruginosa and S. aureus biofilms. Furthermore, SEM analyses revealed crack and gap formations on P. aeruginosa. biofilm surface and decreased expression of P. aeruginosa biofilm maturation and virulence genes (lasR, rhlR and rhlA) was observed after treatment by larval extract in combination with antibiotics.

Histological technique to detect the physiological age of the malaria vector mosquito Anopheles pharoensis (Diptera: Culicidae).

The risk of malaria recurrence increases due to the main vector, Anopheles pharoensis. The physiological age of the mosquito population is needed to expect malaria vector dynamics. The number of completed gonotrophic cycles is of great importance in determining the physiological age of females. A technique has been described that focuses on the number of dilatations remaining in the ovarioles after each oviposition to determine how many blood meals have been taken. At each gonotrophic cycle, the chances of infection of the vectors are repeated. The histological changes that occur immediately in the ovarioles and ovulation itself were studied. Under the influence of the contractions of the ovarian muscles, the eggs begin to move over the distal end of the ovariole into the inner oviduct. The terminal pedicle is markedly dilated near the diameter of the eggs. After the expulsion of the mature eggs, ovariole dilations were found at the point of their development in the terminal pedicle due to the accumulation of nurse cell remnants and follicular epithelium. The results were used to develop epidemiological localization and to evaluate the effectiveness of antimalaria interventions. The ovarian inspection often provides a technique to distinguish nulliparous from parous female anophelines. In addition, this study can provide basic entomological knowledge on the physiological age of mosquitoes by considering the histological changes in the ovaries, which allow the evaluation of vector management strategies in the field.

Morphological Re-Description and 18 S rDNA Sequence Confirmation of the Pinworm Aspiculuris tetraptera (Nematoda, Heteroxynematidae) Infecting the Laboratory Mice Mus musculus.

Aspiculuris tetraptera is a heteroxynematid nematoda infecting most of the laboratory animals, occasionally mice which represent the mostly used animal for biological, medical, and pharmacological studies. The present study aimed to investigate the prevalence of nematode parasites infection in the laboratory mice Mus musculus in Egypt. Morphologically, this oxyurid possessed four distinct cephalic papillae on a cephalic plate, with three small rudimental lips carrying two sessile poorly developed labial papillae and one pair of amphidial pores. Esophagus divided into cylindrical corpus and globular bulb. Distinct cervical alae interrupted at the level of esophago-intestinal junction forming an acute angle. At the caudal end, twelve caudal papillae in male worms while an ovijector apparatus opening and a vulva surrounded by protruded lips in females were observed. The general morphological criteria include this nematode with other Aspiculuris species which were compared in the present study. Molecular characterization based on 18SSU rDNA sequencing performed to confirm the taxonomic position of this species and to documents the morphological data. Sequence alignment detects a percent of identity up to 88.0% with other Heteroxynematidae species. Phylogenetic analysis showed that the present recorded is a putative sister taxon to A. tetraptera recorded in a previous study. The SSU rDNA sequence has been deposited in the GenBank under the accession no. MG019400.

Light microscopic study of four plagiorchiid trematodes infecting marine fish in the south-eastern Mediterranean Sea, Alexandria City, with descriptions of two new species.

During the present investigation, a total of 220 fish specimens belonging to three different species, namely, little tunny Euthynnus alletteratus, African snook Lates niloticus, and striped red mullet Mullus surmuletus, were collected from January-November 2016 from the coasts off Abu Qir landing site, Alexandria City, south-eastern Mediterranean Sea, Egypt. The collected fish samples were dissected and examined for the presence of helminth parasites. Twenty-three out of 220 (10.45%) fish specimens were found to be naturally infected with four species of trematode parasites belonging to three different families of the order Plagiorchiida. The recovered parasite species were collected and identified by applying light microscopic examinations. The present study recorded two new parasite species, namely, Stephanostomum alletterani sp. nov. and Bathycreadium mulli sp. nov., belonging to the families Acanthocolpidae and Opecoelidae and infecting E. alletteratus and M. surmuletus, respectively and re-descriptions of the two remaining species, namely, Acanthostomum spiniceps and Aponurus mulli of the families Acanthostomatidae and Opecoelidae, respectively, to clarify the measurements of some body parts. Morphological and morphometric characterizations revealed some differences between the present species and other related species detected previously. Future studies are recommended to include advanced molecular characteristics for these species.

Nanoparticles as effective acaricides against ticks-A review.

Ticks serve as vectors of a wide range of infectious agents deleterious to humans and animals. Tick bite prevention is based to a large extent on the use of chemical repellents and acaricides. However, development of resistance in targeted ticks, environmental pollution, and contamination of livestock meat and milk are major concerns. Recently, metal, metal oxide and carbon nanoparticles, particularly those obtained through green fabrication routes, were found to be highly effective against a wide array of arthropod pests and vectors. We summarize current knowledge on the toxicity of nanoparticles against tick vectors of medical and veterinary importance. We also discuss the toxicity of products from botanical- and bacterial-based as well as classic chemical nanosynthesis routes, showing differences in bioactivity against ticks based on the products used for the fabrication of nanoparticles. Further research is needed, to validate the efficacy of nanoparticle-based acaricides in the field and clarify mechanisms of action of nanoparticles against ticks. From a technical point of view, the literature analyzed here showed little standardization of size and weight of tested ticks, a lack of uniform methods to assess toxicity and concerns related to data analysis. Finally, an important challenge for future research is the need for ecotoxicology studies to evaluate potential negative effects on non-target organisms and site contamination arising from nanoparticle-based treatments in close proximity of livestock and farmers.

Morphological re-description and phylogenetic relationship of five myxosporean species of the family Myxobolidae infecting Nile tilapia.

Freshwater fish have a major economic and nutritional importance worldwide. Myxosporeans are highly dangerous parasites that infect different fish species, causing severe damage to a large number of economically important species, especially in aquaculture. We conducted a survey of myxosporean parasites infecting Nile tilapia Oreochromis niloticus (Perciformes: Cichlidae) collected from different localities along the River Nile passing through Giza province, Egypt. Out of 100 fish specimens collected, 45 were found to be naturally infected with these parasites in the region of the trunk kidney. Light microscopic examination revealed the presence of 5 distinct myxosporean species belonging to 2 different genera, viz. Myxobolus and Triangula, belonging to the family Myxobolidae; all 5 species have been previously described. Morphological characteristics, host specificity and geographical distribution, tissue tropism, and molecular analysis of the partial sequence of small subunit ribosomal DNA gene revealed that the recovered myxosporean species described herein were genetically distinct from other myxozoan species but had 95% sequence similarity to M. cerebralis. Also, phylogenetic analysis placed the present myxosporean species in the freshwater Myxobolus clade, which is a sister group of freshwater Myxobolus/Henneguya species.

Morphological description of Cosmocerca sp. (Nematoda: Cosmocerdidae) from the Mascarene grass frog Ptychadena cf. mascareniensis (Amphibia: Ptychadenidae). A light and scanning electron microscopic studies.

The Mascarene grass frog Ptychadena cf. mascareniensis is a species of frog with a vast area of distribution in Africa. A total of 300 frog specimens were collected from different localities at El-Giza province, Egypt; then dissected and examined for the presence of parasitic infection. Only eighty six (28.66%) specimens were found to be naturally infected with nematode parasite. Seasonally, the prevalence of infection was reached its maximum value of 74.66% during summer and minimum values of 26.66% (20/75), 13.33% (10/75) during spring and autumn, respectively; while no records were observed during winter season. The morphology of the recovered parasite was studied by using light and scanning electron microscopy. The adult worm characterized by anterior extremity with small mouth opening being surrounded by three lips provided with four sub-median cephalic papillae and one pair of lateral amphids. Body measurements showed that male worms were smaller than females measuring 1.22-2.43 (2.21 ± 0.1) mm in length and 0.21-0.34 (0.29 ± 0.01) mm in width. Females measured 1.9-3.7 (2.8 ± 0.1) mm in length and 0.24-0.42 (0.38 ± 0.01) mm in width. Comparing the present parasite with other species of the same genus described previously, several similarities were observed. However, peculiar new characteristics such as the arrangement of plectanes and somatic papillae, the presence of gubernaculum, the position of nerve ring, excretory pore, and vulval opening make it reasonable belongs to the family Cosmocercidae and identified as Cosmocerca sp. In addition, the present study was the first report for occurrence of cosmocercid species from the Mascarene grass frog in Egypt.

Morphological re-description of Electrotaenia malapteruri (Cestoda: Proteocephalidae) and Dujardinnascaris malapteruri (Nematoda: Heterocheilidae) infecting the Electric catfish Malapterurus electricus and heavy metal accumulation in host and parasites in relation to water and sediment analysis in Lake Manzala, North Delta, Egypt.

Parasites are one of the most serious limiting factors in aquaculture. The Electric catfish Malapterurus electricus was subjected to study the prevalence and mean intensity of parasitic infections throughout the whole year of 2015. Heavy metals accumulation in host fish and parasites were determined in relation to water quality and sediments of two different sites of Lake Manzala (Manzala and Bahr El-Baqar), Egypt. A total of 100 specimens of Electric catfish were collected and examined for the presence of helminth parasites. Two parasite species were recovered and morphologically identified. These were cestoda Electrotaenia malapteruri and nematode Dujardinnascaris malapteruri. Heavy metal analysis in water and sediments showed that measured heavy metals in Bahr El-Baqar were found in risky levels higher than permissible limits and Manzala site. Sediments were found to contain a higher level of metals than water samples. Heavy metals accumulation in recovered parasites and their host were also determined and showed significantly higher concentrations in parasites compared to their host tissues. According to bioconcentration factors, E. malapteruri showed that highest accumulation rate for all recorded elements up to 302. Essential elements like Cu and Fe were found in significantly higher concentrations in D. malapteruri, whereas E. malapteruri accumulated elements Cd, Pb, Ni, Mn, Zn and Ca to a significantly higher degree. Accordingly, the ratios (C[D.malapteruri]/C[E. malapteruri]) for most essential elements were higher than 0.5. Therefore, fish cestodes can be regarded as useful bio-indicators more than nematodes when evaluating the environmental pollution of aquatic ecosystems by heavy metals.

Acute larvicidal toxicity of five essential oils (Pinus nigra, Hyssopus officinalis, Satureja montana, Aloysia citrodora and Pelargonium graveolens) against the filariasis vector Culex quinquefasciatus: Synergistic and antagonistic effects.

Mosquito vector control is facing a number of important and timely challenges, mainly due to the rapid development of pesticide resistance and environmental concerns. In this scenario, screening of botanical resources for their mosquitocidal activity may offer effective and eco-friendly tools against Culicidae vectors. Culex quinquefasciatus Say (Diptera: Culicidae) is a vector of lymphatic filariasis and of dangerous arboviral diseases, such as West Nile and St. Louis encephalitis. In this study, the chemical composition of five essential oils obtained from different plants, namely Pinus nigra J.F. Arnold var. italica (Pinaceae), Hyssopus officinalis L. subsp. aristatus (Lamiaceae), Satureja montana L. subsp. montana (Lamiaceae), Aloysia citriodora Palau (Verbenaceae) and Pelargonium graveolens L'Hér (Geraniaceae), was investigated by GC-MS analysis. Furthermore, it was evaluated their acute toxicity on larvae of C. quinquefasciatus. Then, the most effective oils were selected, in order to focus on the potential synergistic and antagonistic effects, testing them in binary mixtures on C. quinquefasciatus larvae. Results showed that the higher effectiveness was obtained by S. montana subsp. montana essential oil (LC50=25.6µL·L-1), followed by P. nigra var. italica (LC50=49.8µL·L-1) and A. citriodora (LC50=65.6µL·L-1), while the other essential oils showed LC50 values higher than 90µL·L-1. The larvicidal effectiveness can be enhanced by preparing simple binary mixtures of essential oils, such as S. montana+A. citriodora (ratio 1:1), which showed higher larvicidal toxicity (LC50=18.3µL·L-1). On the other hand, testing S. montana+P. nigra (1:1) an antagonistic effect was detected, leading to a LC50 (72.5µL·L-1) higher than the LC50 values calculated for the two oils tested separately. Overall, our results add useful knowledge to allow the employ of synergistic essential oil blends as effective, cheap and eco-friendly mosquito larvicides.

Malaria relapses were already known before 1900-a discussion.

For a long time, only two phases of the life cycle of the agents of malaria parasites were known: the cycle inside the mosquito body and the cycle in the red blood cells of humans as intermediate hosts. A possible tissue development cycle inside humans, however, had already been proposed before 1900. In general, Pieter Klaesz Pel is considered the first scientist who has described such a tissue cycle. However, a closer look at Pel's work shows that he still followed an old (conservative) way of thinking, since he still referred to "malaria poison and malaria miasma." Thus, the first idea of a possible tissue cycle must be searched in the work of earlier scientists. Referring to their observations on malaria, Vassilij Danilevsky, Arman Ruffer, Camillo Golgi and Battista Grassi suspected developing parasites in internal organs, before they can be found in the bloodstream.

Morphological and ultrastructural characteristics of Myxobolus ridibundae n. sp. (Myxosporea: Bivalvulida) infecting the testicular tissue of the marsh frog Rana ridibunda (Amphibia: Ranidae) in Egypt.

Myxozoans are one of the most economically important groups of protozoan parasites causing many serious diseases of their hosts. In the present study, a total of 60 live adult male specimens of the marsh frog Rana ridibunda have been randomly captured during the period of January-December 2015 in different areas at Kafr El-Sheikh Governorate, Egypt and were examined for infection by myxosporidian parasites. A total of 48 (80.0 %) out of 60 frog specimens were found to be infected with Myxobolus species. Parasitic infection was restricted to the testicular tissue of the examined frogs. Macroscopic cysts (plasmodia) which heavily infested different parts of the testes were recovered. Morphological and ultrastructural characteristics of these myxosporidian species were carried out using light and transmission electron microscopy. Plasmodia measured 0.16-0.53 (0.34 ± 0.01) mm in diameter. Mature spores appeared oval in frontal view, measuring 8.9-11.5 (9.6 ± 0.1) µm in length and 7.5-9.1 (8.4 ± 0.1) µm in width containing 5-6 turns of polar filaments. Morphometric characterization revealed that the very small size of the present Myxobolus species was the most distinctive feature that separates them from all previously described Myxobolus species. Ultrastructural analysis showed that the plasmodia are surrounded by a plasma membrane with numerous pinocytotic protrusions extending toward the host cell. The generative cells and the different developmental stages are arranged at the periphery of the plasmodia, while immature and mature spores are centrally located. Sporogenesis, capsulogenesis, valvogenesis, and spore maturation of the present parasite are also described. The present species is described as Myxobolus ridibundae and represents a new species.

Application of ethnobotanical repellents and acaricides in prevention, control and management of livestock ticks: A review.

Ticks transmit at least the same number or even more pathogens than any other group of blood-feeding arthropods worldwide affecting humans and animals. The eco-friendly control and management of tick vectors in a constantly changing environment is a crucial challenge. Besides the development of vaccines against ticks, IPM practices aimed at reducing tick interactions with livestock, emerging pheromone-based control tools, and few biological control agents, the extensive employment of acaricides and tick repellents still remain the most effective and ready-to-use strategies. However, the former is limited by the development of growing resistances as well as environmental concerns. Exploiting plants and plant products as sources of effective tick repellents and acaricides represents a promising strategy. In this scenario, the preservation of ethnobotanical information on repellent and acaricidal potential of plants is crucial. Here, we evaluated relevant information published in recent years, focused on plants used as repellents and acaricides against tick vectors in different regions worldwide. We selected a total of 238 plant species, which are traditionally used against ticks by native and local communities of Africa (Kenya, Uganda, Zimbabwe, South Africa), Europe (Serbia, Macedonia, Romania), Asia (Pakistan, India) and America (Brazil, Canada), from 56 families. However, only 7 families (i.e. Asteraceae, Euphorbiaceae, Fabaceae, Lamiaceae, Meliaceae, Apocynaceae and Solanaceae) represent the major quote (46%) of all plant species. We evaluated the differences in acaricidal and repellent efficacy of different formulations used. In the final section, implications arising from the surveyed anti-tick ethnobotanical knowledge and challenges for its future are discussed.

Morphological re-description and molecular characterization of Kudoa pagrusi (Myxosporea: Multivalvulida) infecting the heart muscles of the common sea bream fish Pagrus pagrus (Perciformes: Sparidae) from the Red Sea, Egypt.

In the present study, 100 samples of different sizes of the common sea bream fish Pagrus pagrus were collected from the Egyptian water along the Gulf of Suez, Red Sea and examined for the prevalence of myxosporidian parasites in general and Kudoa spp. in particular. Fish samples were thoroughly externally examined. After dissection, all the internal organs were removed and examined. A total of 60 out of 100 fish specimens were found to be infected with Kudoa stages. Parasitic infection was restricted to the heart muscles of the examined fish. None of the other organs was found to be infected. Macroscopic cysts (plasmodia) heavily infested the different parts of the heart muscles. Each plasmodium measured 1.2-2.5 (1.53 ± 0.2) mm × 0.63-0.80 (0.65 ± 0.2) mm. Mature spores are quadratic in shape in the apical view showing four equal valves and four symmetrical polar capsules. Fresh spores were 5.0-7.1 (5.7 ± 0.2) µm long × 5.4-8.5 (6.1 ± 0.3) µm wide. On the basis of spore morphology, the present species was identified as Kudoa pagrusi. Morphometric characterization revealed that the relatively small size of this Kudoa species was the distinctive feature that separates it from all previously described species. Molecular analysis based on small subunit ribosomal DNA (SSU rDNA) sequences revealed that the highest percentage of identity was observed with K. scomberomori and followed by K. shiomitsui, K. hypoepicarclialis, K. amamiensis, and K. kenti. The kudoid spores showed morphometric variations to some extents but had essentially identical nucleotide sequences of the SSU rDNA gene sequences closest to those of K. scomberomori and K. shiomitsui recorded from elasmobranchs in the Indo-Pacific Ocean. The present findings support the identification of an ancestral marine origin of the present Kudoa species.

Tick repellents and acaricides of botanical origin: a green roadmap to control tick-borne diseases?

Arthropods are dangerous vectors of agents of deadly diseases, which may hit as epidemics or pandemics in the increasing world population of humans and animals. Among them, ticks transmit more pathogen species than any other group of blood-feeding arthropods worldwide. Thus, the effective and eco-friendly control of tick vectors in a constantly changing environment is a crucial challenge. A number of novel routes have been attempted to prevent and control tick-borne diseases, including the development of (i) vaccines against viruses vectored by ticks; (ii) pheromone-based control tools, with special reference to the "lure and kill" techniques; (iii) biological control programmes relying on ticks' natural enemies and pathogens; and (iv) the integrated pest management practices aimed at reducing tick interactions with livestock. However, the extensive employment of acaricides and tick repellents still remains the two most effective and ready-to-use strategies. Unfortunately, the first one is limited by the rapid development of resistance in ticks, as well as by serious environmental concerns. On the other hand, the exploitation of plants as sources of effective tick repellents is often promising. Here, we reviewed current knowledge concerning the effectiveness of plant extracts as acaricides or repellents against tick vectors of public health importance, with special reference to Ixodes ricinus, Ixodes persulcatus, Amblyomma cajennense, Haemaphysalis bispinosa, Haemaphysalis longicornis, Hyalomma anatolicum, Hyalomma marginatum rufipes, Rhipicephalus appendiculatus, Rhipicephalus (Boophilus) microplus, Rhipicephalus pulchellus, Rhipicephalus sanguineus and Rhipicephalus turanicus. Eighty-three plant species from 35 botanical families were selected. The most frequent botanical families exploited as sources of acaricides and repellents against ticks were Asteraceae (15 % of the selected studies), Fabaceae (9 %), Lamiaceae (10 %), Meliaceae (5 %), Solanaceae (6 %) and Verbenaceae (5 %). Regression equation analyses showed that the literature grew by approximately 20 % per year (period: 2005-2015). Lastly, in the final section, insights for future research are discussed. We focused on some caveats for future data collection and analysis. Current critical points mainly deal with (a) not uniform methods used, which prevent proper comparison of the results; (b) inaccurate tested concentrations, frequently 100 % concentration corresponded to the gross extract, where the exact amounts of extracted substances are unknown; and (c) not homogeneous size of tested tick instars and species. Overall, the knowledge summarized in this review may be helpful for comparative screening among extensive numbers of plant-borne preparations, in order to develop newer and safer tick control tools.

Mosquito vectors and the spread of cancer: an overlooked connection?

Mosquitoes (Diptera: Culicidae) represent a key threat for millions of humans and animals worldwide, vectoring important pathogens and parasites, including malaria, dengue, filariasis, and Zika virus. Besides mosquito-borne diseases, cancers figure among the leading causes of mortality worldwide. It is expected that annual cancer cases will rise from 14 million in 2012 to 22 million within the next two decades. Notably, there are few contrasting evidences of the relationship between cancer and mosquito-borne diseases, with special reference to malaria. However, analogies at the cellular level for the two diseases were reported. Recently, a significant association of malaria incidence with all cancer mortality in 50 USA states was highlighted and may be explained by the ability of Plasmodium to induce suppression of the immune system. However, it was hypothesized that Anopheles vectors may transmit obscure viruses linked with cancer development. The possible activation of cancer pathways by mosquito feeding events is not rare. For instance, the hamster reticulum cell sarcoma can be transmitted through the bites of Aedes aegypti by a transfer of tumor cells. Furthermore, mosquito bites may influence human metabolic pathways following different mechanisms, leading to other viral infections and/or oncogenesis. Hypersensitivity to mosquito bites is routed by a unique pathogenic mechanism linking Epstein-Barr virus infection, allergy, and oncogenesis. During dengue virus infection, high viral titers, macrophage infiltration, and tumor necrosis factor alpha production in the local tissues are the three key important events that lead to hemorrhage. Overall, basic epidemiological knowledge on the relationships occurring between mosquito vector activity and the spread of cancer is urgently needed, as well as detailed information about the ability of Culicidae to transfer viruses or tumor cells among hosts over time. Current evidences on nanodrugs with multipotency against mosquito-borne diseases and cancers are reviewed, with peculiar attention to their mechanisms of action.

Henneguya collaris sp. nov., (Myxosporidia), parasite of the Greenband Parrotfish Scarus collana Rüppell, 1835 (Actinopterygii, Scaridae) from the Red Sea, Egypt. A light and electron microscopic study.

The phylum Myxozoa comprises more than 2180 species, almost all of which are considered to be obligate parasites of aquatic fishes. In the present study, Henneguya collaris sp. nov. is the first described histozoic myxozoan species of the genus Henneguya infecting the kidney of the greenband parrotfish Scarus collana (Actinopterygii, Scaridae). One hundred and eighty specimens of fish were collected randomly during the period from September 2014 to October 2015 from boat landing sites and the market places at Hurghada City along the Red Sea in Egypt. Of these, 90 (50 %) specimens were infected. Light microscopic examination showed that the infection was detected as mature spores with two polar capsules regularly arranged at the anterior pole of each spore and extruded polar filaments free in the kidney tissue. The spore body was oval in shape, measured 7.1 ± 0.2 (6.2-8.4) µm in length and 6.3 ± 0.2 (5.8-7.0) µm in width, with a bifurcated caudal process of equal length, reaching 6.3 ± 0.2 (5.8-7.0) µm in length. Polar capsules were 3.4 ± 0.2 (3.0-4.2) µm in length and 1.9 ± 0.2 (1.6-2.4) µm in width with 6-8 (10) turns of polar filaments. Ultrastructural analysis showed that the spore development was asynchronous. Sporogenesis, capsulogensis, valvogenesis, and spore maturation of the present parasite were also described. The present species was compared morphologically with the spore characteristics of the most similar species of Henneguya spp. recorded previously from different geographical areas taking into account the stage and dimensions of the spore body, tails, and polar filament coils, including their number and the most important characteristic features that distinguish them from the present species. Considering the data obtained, the material described herein represents a new species and the name Henneguya collaris sp. nov. is proposed.

Clinical implications of a gradual dormancy concept in malaria.

Malaria recurrences after an initially successful therapy and malarial fever occurring a long time after infection are well-known problems in malariology. Currently, two distinct types of malaria recurrences are defined: recrudescence and relapse. A recrudescence is thought to originate from circulating Plasmodium blood stages which do not cause fever before a certain level of a microscopically detectable parasitemia is reached. Contrary, a relapse is thought to originate from quiescent intracellular hepatic parasite stages called hypnozoites. Recrudescences would typically occur in infections due to Plasmodium falciparum. Plasmodium knowlesi, and Plasmodium malariae, whereas relapses would be caused exclusively by Plasmodium vivax and Plasmodium ovale. This schematic view is, however, insufficiently supported by experimental evidence. For instance, hypnozoites of P. ovale have never been experimentally documented. On the other hand, the nonfinding of P. malariae hypnozoites turned into the proof for the nonexistence of P. malariae hypnozoites. Clinical relapse-type recurrences have been observed in both P. ovale and P. malariae infections, and decade-long incubation times have also been reported in P. falciparum infections. We propose a gradual hypothesis in accordance with the continuity concept of biological evolution: both, relapse and recrudescence may be potentially caused by all Plasmodium spp. We hypothesize that the difference between the various Plasmodium spp. is quantitative rather than qualitative: there are Plasmodium spp. which frequently cause relapses such as P. vivax, particularly the P.v. Chesson strain, species which cause relapses less frequently, such as P. ovale and sometimes P. malariae, and species which may exceptionally cause relapses such as P. falciparum. All species may cause recrudescences. As clinical consequences, we propose that 8-aminquinolines may be considered in a relapse-type recrudescence regardless of the causal Plasmodium sp., whereas primaquine relapse prevention might not be routinely indicated in malaria due to P. ovale.

Declining malaria, rising of dengue and Zika virus: insights for mosquito vector control.

The fight against mosquito-borne diseases is a challenge of huge public health importance. To our mind, 2015 was an extraordinary year for malaria control, due to three hot news: the Nobel Prize to Youyou Tu for the discovery of artemisinin, the development of the first vaccine against Plasmodium falciparum malaria [i.e. RTS,S/AS01 (RTS,S)], and the fall of malaria infection rates worldwide, with special reference to sub-Saharan Africa. However, there are major challenges that still deserve attention, in order to boost malaria prevention and control. Indeed, parasite strains resistant to artemisinin have been detected, and RTS,S vaccine does not offer protection against Plasmodium vivax malaria, which predominates in many countries outside of Africa. Furthermore, the recent outbreaks of Zika virus infections, occurring in South America, Central America and the Caribbean, represent the most recent of four arrivals of important arboviruses in the Western Hemisphere, over the last 20 years. Zika virus follows dengue (which slyly arrived in the hemisphere over decades and became more aggressive in the 1990s), West Nile virus (emerged in 1999) and chikungunya (emerged in 2013). Notably, there are no specific treatments for these arboviruses. The emerging scenario highlights that the effective and eco-friendly control of mosquito vectors, with special reference to highly invasive species such as Aedes aegypti and Aedes albopictus, is crucial. The concrete potential of screening plant species as sources of metabolites for parasitological purposes is worthy of attention, as elucidated by the Y. Tu's example. Notably, plant-borne molecules are often effective at few parts per million against Aedes, Ochlerotatus, Anopheles and Culex young instars, can be used for the rapid synthesis of mosquitocidal nanoformulations and even employed to prepare cheap repellents with low human toxicity. In addition, behaviour-based control tools relying to the employ of sound traps and the manipulation of swarming behaviour (i.e. "lure and kill" approach) are discussed. The importance of further research on the chemical cues routing mosquito swarming and mating dynamics is highlighted. Besides radiation, transgenic and symbiont-based mosquito control approaches, an effective option may be the employ of biological control agents of mosquito young instars, in the presence of ultra-low quantities of nanoformulated botanicals, which boost their predation rates.

Modeling the habitat suitability for the arbovirus vector Aedes albopictus (Diptera: Culicidae) in Germany.

Climatic changes raise the risk of re-emergence of arthropod-borne virus outbreaks globally. These viruses are transmitted by arthropod vectors, often mosquitoes. Due to increasing worldwide trade and tourism, these vector species are often accidentally introduced into many countries beyond their former distribution range. Aedes albopictus, a well-known disease vector, was detected for the first time in Germany in 2007, but seems to have failed establishment until today. However, the species is known to occur in other temperate regions and a risk for establishment in Germany remains, especially in the face of predicted climate change. Thus, the goal of the study was to estimate the potential distribution of Ae. albopictus in Germany. We used ecological niche modeling in order to estimate the potential habitat suitability for this species under current and projected future climatic conditions. According to our model, there are already two areas in western and southern Germany that appear suitable for Ae. albopictus under current climatic conditions. One of these areas lies in Baden-Wuerttemberg, the other in North-Rhine Westphalia in the Ruhr region. Furthermore, projections under future climatic conditions show an increase of the modeled habitat suitability throughout Germany. Ae. albopictus is supposed to be better acclimated to colder temperatures than other tropical vectors and thus, might become, triggered by climate change, a serious threat to public health in Germany. Our modeling results can help optimizing the design of monitoring programs currently in place in Germany.