Sergentomyia (Neophlebotomus) monticola, a new species of sand fly (Diptera: Psychodidae) from the Western Ghats,Thiruvananthapuram District,Kerala, India

Sergentomyia (Neophlebotomus) monticola, a new species of sand fly (Diptera: Psychodidae), from the Kani tribal settlements, Thiruvananthapuram District, Kerala, southern India was described. These settlements were located in the Western Ghats, which is one of the 25 biodiversity hotspots in the world. Morphological characters of male and female specimens of Sergentomyia (Neophlebotomus) monticola were described with illustrations and its taxonomic position is defined within the genus. The DNA barcode analysis showed that both male and female specimens of the species were belonging to a single taxonomic category. The genetic distance with the most similar taxonomic neighbour was 14.61%, which confirms its distinctness from its congeners. Voucher specimens of the new species were deposited at the museum, Vector Control Research Centre (Indian Council of Medical Research), Puducherry, India, Zoological Survey of India, India and Smithsonian National Museum of Natural History (NMNH), Washington, D.C., USA.     

A new species of Syphacia (Seuratoxyuris) (Nematoda: Oxyuridae) from Sooretamys angouya Fischer, 1814 (Rodentia: Cricetidae) in Argentina

Syphacia (Seuratoxyuris) hugoti n. sp. (Nematoda: Oxyuridae) is described from the cecum of Sooretamys angouya (Cricetidae: Sigmodontinae: Oryzomyini) captured in Formosa Province, Argentina. The diagnosis of the subgenus is emended, and the new species is separated from eight congeners by the distribution of submedian papillae and amphids, shape of the cephalic plate, presence of deirids, absence of cervical and lateral alae, length of the spicule, structure of the accessory hook of the gubernaculum and distance of excretory pore and vulva from the anterior extremity. The analysis suggests that S. (Se.) oryzomyos should be removed from Seuratoxyuris and redesignated as S. (Syphacia) oryzomyos n. comb. To date, of the species of Syphacia found in South and North American, 7 parasitize Oryzomyini rodents, of which two are distributed in Argentina. The present study constitutes the first record of the subgenus Seuratoxyuris from Argentina and the third record of a Syphacia species from rodents of the tribe Oryzomyini.     

Spatial distribution and r-DNA second internal transcribed spacer characterization of Anopheles dirus (Diptera: Culicidae) complex species in north-east India

The identity and distribution of the prevalent member species of the Anopheles dirus complex mosquitoes in the north-eastern region of India was investigated in a cross-sectional study. We altogether collected 267 individuals of An. dirus s.l. from 27 forested/forest fringed locations spread across the seven north-eastern states, identified the species using a ribosomal DNA (r-DNA) second internal transcribed spacer (ITS2) based allele specific polymerase chain reaction (ASPCR) method and sequenced the ITS2 locus in a sub set of mosquitoes. An. baimaii was identified as the main, almost exclusive (266/267), species of the Dirus complex throughout the north-east India with no intraspecific variation in the 479 base pair long ITS2 sequences in 59 of the 60 individuals sequenced. Ribosomal DNA of one individual from Assam state did not amplify in the ASPCR, possessed 786 base pair long ITS2 sequence and showed 99.7% similarity with the sequence of An. dirus species D (An. baimaii) from Yunnan province of China, later referred to as species X of the Dirus complex. These observations suggest the presence of another, possibly the new, species of the Dirus complex, sympatric with An. baimaii, in Assam warranting investigations on its distribution, biology and role in human malaria transmission in north-east India.     

Cutaneous leishmaniasis caused by Leishmania (L.) major infection in Sindh province, Pakistan

Leishmaniasis is endemic in Pakistan and is wide-spread throughout the country. Polymerase chain reaction (PCR) was performed to identify the Leishmania species present in cutaneous leishmaniasis (CL) patients from new endemic areas of the central part of Sindh province, Pakistan. The PCR primers used were designed for the identification and differentiation of Leishmania (Leishmania) major and Leishmania (Leishmania) tropica species, and PCR bands at 620 and 830 bp of the parasite-specific kinetoplast DNA sequences was identified for L. (L.) major and L. (L.) tropica, respectively. Among a total of 144 DNA samples purified from the skin biopsies of clinically suspected CL patients, 108 (75%) were positive for PCR amplification. Out of the 108 cases, 105 (97.2%) were determined to be positive for L. (L.) major infection, and 3 (2.8%) were positive for L. (L.) tropica infection. It was concluded that CL caused by L. (L.) major is the main source of infection in the central part of Sindh province in Pakistan. This rapid screening technique could be used for the diagnosis of a large number of samples from skin lesions, which commonly contain other bacterial and fungal infections.     

Finding of Parastrongylus cantonensis (Chen, 1935) in Rattus rattus in Tenerife, Canary Islands (Spain)

Parastrongylus cantonensis is a parasite of murid rodents that can infect humans and cause health problems as eosinophilic meningitis. Although it is endemic in south Asia, the Pacific islands, Australia, USA, and a few Caribbean islands, it has been extended to new geographical regions. In the Canary Islands (Spain) a survey of helminths of Rattus rattus, Rattus norvegicus and Mus musculus domesticus was carried out. Furthermore, five species of molluscs were examined for nematode larvae to determine whether they are potential intermediate hosts of P. cantonensis. Nematodes were found in the lungs of 15% of 67 R. rattus examined in Tenerife, one of the four studied islands, with a prevalence of 20% in the highest focus of infection. Based on morphological and molecular analysis, with the complete internal transcribed spacer 2 (ITS-2) and a fragment of the small subunit ribosomal RNA (SSU rRNA) nucleotide sequences, nematodes were identified as P. cantonensis. Larval nematodes found from snails and slugs were identified as third-stage (L₃) Metastrongyloidea, but the molecular study showed that they did not belong to P. cantonensis. This is the first finding of angiostrongyliasis in rats in the Canary Islands (Spain). New molecular data for this species and Parastrongylus dujardini are reported. The presence of P. cantonensis in Tenerife could be of importance from the public health point of view. Further studies are required in order to look for other potential foci of infections in the Canary Islands.     

Molecular evidence of misidentification of Anopheles minimus as Anopheles fluviatilis in Assam (India)

Anophelesminimus s.l. and Anophelesfluviatilis s.l., two closely related taxa, are reported vectors of malaria in Assam state of India. We determined the DNA sequences of morphologically identified A. minimus s.l. and A. fluviatilis s.l. collected from the Kamrup district in Assam, for two rDNA loci—internal transcribed spacer 2 (ITS2) and D3 domain of 28S rDNA (28S-D3). Analysis of rDNA data revealed that the sequences of both the morphologically identified A. minimus s.l. and A. fluviatilis s.l. from Assam are identical, homologous to the sequences of A. minimus s.s. (former species A) and different from that of all the reported members of the Fluviatilis Complex (species S, T and U). This indicates that A. fluviatilis s.l. being reported in Kamrup district, Assam, in low density, mostly during January to April, is actually a hypermelanic and seasonal variant of A. minimus. It was also found that the banding pattern on chromosome arm 2 (which bears species-diagnostic inversions for the Fluviatilis Complex) of A. minimus and of A. fluviatilis s.l. from Assam is homosequential with A. fluviatilis species U suggesting that probably previously described A. fluviatilis U from Assam were also A. minimus.     

Molecular differentiation of Angiostrongylus taxa (Nematoda: Angiostrongylidae) by cytochrome c oxidase subunit I (COI) gene sequences

Nematodes of the genus Angiostrongylus are parasites of rodents and carnivores. They reside in the pulmonary or mesenteric arteries of their hosts. Two species are pathogenic in humans - Angiostrongylus cantonensis causes eosinophilic meningitis or meningoencephalitis, and Angiostrongylus costaricensis produces abdominal angiostrongyliasis. In addition Angiostrongylus malaysiensis may have the potential of being pathogenic in humans. The mitochondrial gene cytochrome c oxidase subunit I (COI) of these Angiostrongylus species and three geographical isolates (China, Hawaii and Thailand) of A. cantonensis were studied by polymerase chain reaction amplification and DNA sequencing. COI sequences of A. cantonensis, A. costaricensis and Angiostrongylus vasorum in the GenBank were included for comparison. Phylogenetic analysis by maximum-likelihood (ML), maximum-parsimony (MP), neighbour-joining (NJ) and Bayesian inference (BI) produced similar tree topology except variation in the bootstrap support values. There were two major clades - (1) A. cantonensis and A. malaysiensis, and (2) A. costaricensis and A. vasorum. The three geographical isolates of A. cantonensis formed a clade with low to high bootstrap values, and consisted of two subclades: (a) China and Hawaii isolates, and (b) monophyletic Thailand isolate. The individuals of each isolate formed a distinct cluster. In the second major clade, the Europe isolates of A. vasorum were distinctly different from the Brazil isolates. For A. costaricensis, the Costa Rica isolate was distinct from the Brazil isolate with an uncorrected (p) distance of 11.39%, indicating the possible occurrence of cryptic species. The present results indicate that COI sequences might be a useful marker for differentiating geographical isolates of A. cantonensis and in uncovering cryptic species. Efforts are being made to carry out an extensive collaborative study to cover a wide range of Angiostrongylus species and geographical isolates.     

Phylogenetic relationships among species of Anopheles (Nyssorhynchus) (Diptera, Culicidae) based on nuclear and mitochondrial gene sequences

Phylogenetic relationships among 21 species of mosquitoes in subgenus Nyssorhynchus were inferred from the nuclear white and mitochondrial NADH dehydrogenase subunit 6 (ND6) genes. Bayesian phylogenetic methods found that none of the three Sections within Nyssorhynchus (Albimanus, Argyritarsis, Myzorhynchella) were supported in all analyses, although Myzorhynchella was found to be monophyletic at the combined genes. Within the Albimanus Section the monophyly of the Strodei Subgroup was strongly supported and within the Myzorhynchella Section Anopheles antunesi and An. lutzii formed a strongly supported monophyletic group. The epidemiologically significant Albitarsis Complex showed evidence of paraphyly (relative to An. lanei-Myzorhynchella) and discordance across gene trees, and the previously synonomized species of An. dunhami and An. goeldii were recovered as sister species. Finally, there was evidence of complexes in several species, including An. antunesi, An. deaneorum, and An. strodei.     

The life cycle of Ascocotyle (Phagicola) longa (Digenea: Heterophyidae), a causative agent of fish-borne trematodosis

The complete life cycle of the trematode Ascocotyle (Phagicola) longa (Digenea: Heterophyidae) is elucidated by natural observation validated by experimental infections. The natural first intermediate host of A. (P.) longa, an agent of human heterophyiasis in Brazil, is the cochliopid snail Heleobia australis (new first intermediate host). Metacercariae were found encysted in the body musculature, heart, stomach, liver, kidney, spleen, gonads and mesentery of mullets Mugil liza. Hamsters Mesocricetus auratus were experimentally infected with metacercariae of A. (P.) longa obtained from the mullets, and the adults recovered were used to infect the snails H. australis. Rediae and cercariae of A. (P.) longa are described for the first time. The ultrastructure of the tegument of A. (P.) longa shows a change in spination pattern from the cercaria with single-pointed spines to the metacercaria and adult with multipointed, brush-shaped spines. The life cycle of A. (P.) longa is related to estuaries and coastal lagoons where the recruitment of mugilid juveniles occurs. The high prevalence (100%) of A. (P.) longa encysted in the mullets examined within the urban area of Rio de Janeiro indicates the potentially great public health impact of the consumption of raw mullets.     

Variations in the mitochondrial DNA markers in the Anopheles (Cellia) sundaicus population from the Andaman and Nicobar Islands, India

Four sibling species in the Anopheles sundaicus complex have earlier been reported, including species D from the Andaman and Nicobar Islands of India where it constitutes 58% of all Anopheles population and is a major malaria vector. Earlier, we have reported the identical sequences for ribosomal DNA markers among the specimens of A. sundaicus from Andaman and Nicobar islands irrespective of their habitat. These ITS2 sequences were also identical to the reported sequence of variant III of Southeast Asian A. sundaicus. In the present study, we describe variations in three mitochondrial DNA markers among these specimens from Andaman and Nicobar islands. There were two different genotypes for each locus of COI and COII, and three genotypes for cytochrome-b (Cyt-b) locus resulting in three different combined genotypes (genotypes I, II and III) in the population. Specimens with combined genotype I (59%, n = 100) were found only among the A. sundaicus population breeding in fresh water whereas two different multi-loci genotypes i.e. genotype II (25%, n = 100) and genotype III (16%, n = 100) were present in the population breeding in brackish water. Thus, the A. sundaicus population breeding in fresh water was homogenous with single multi-loci genotype and can be distinguished from the heterogenous mosquito population breeding in brackish water with these markers. These Cyt-b and COI sequences of A. sundaicus species D were also different from the reported Southeast Asian species of A. sundaicus.     

First human cases of Leishmania (Viannia) naiffi infection in Ecuador and identification of its suspected vector species

Epidemiological surveillance of leishmaniasis was conducted in a northern Amazonian region of Ecuador, in which cutaneous leishmaniasis cases were recently reported. Sand flies were captured in the military training camp, and the natural infection of sand flies by Leishmania species was examined. Out of 334 female sand flies dissected, the natural infection by flagellates was microscopically detected in 3.9% of Lutzomyia yuilli yuilli and 3.7% of Lutzomyia tortura, and the parasite species were identified as Endotrypanum and Leishmania (Viannia) naiffi, respectively. After the sand fly surveillance, specimens from cutaneous leishmaniasis (CL) patients considered to have acquired the infection in the training camp area were obtained, and the infected parasite species were identified as L. (V.) naiffi. The present study reported first cases of CL caused by L. (V.) naiffi infection in Ecuador. In addition, a high ratio of infection of Lu. tortura by L. (V.) naiffi in the same area strongly suggested that Lu. tortura is responsible for the transmission of L. (V.) naiffi in this area.     

Filamentation temperature-sensitive protein Z (FtsZ) of Wolbachia, endosymbiont of Wuchereria bancrofti: A potential target for anti-filarial chemotherapy

Lymphatic filariasis (LF) is a leading cause of morbidity in the tropical world. It is caused by the filarial parasites Wuchereria bancrofti, Brugia malayi and Brugia timori and transmitted by vector mosquitoes. Currently a programme for the elimination of LF, Global programme for Elimination of Lymphatic Filariasis (GPELF), is underway with the strategy of mass administration of single dose of diethylcarbamazine or ivermectin, in combination with an anthelmintic drug, albendazole. However, antifilarial drugs used in the programme are only microfilaricidal but not or only partially macrofilaricidal. Hence, there is a need to identify new targets for developing antifilarial drugs. Filarial parasites harbor rickettsial endosymbionts, Wolbachia sp., which play an important role in their biology and hence are considered as potential targets for antifilarial chemotherapy development. In this study, one of the cell division proteins of Wolbachia of the major lymphatic filarial parasite, W. bancrofti, viz., filamentation temperature-sensitive protein Z (FtsZ), was explored as a drug target. The gene coding for FtsZ protein was amplified from the genomic DNA of W. bancrofti, cloned and sequenced. The derived amino acid sequence of the gene revealed that FtsZ protein is 396 amino acids long and contained the tubulin motif (GGGTGTG) involved in GTP binding and the GTP hydrolyzing motif (NLDFAD). The FtsZ gene of endosymbiont showed limited sequence homology, but exhibited functional homology with β-tubulin of its host, W. bancrofti, as it had both the functional motifs and conserved amino acids that are critical for enzymatic activity. β-tubulin is the target for the anti-helminthic activity of albendazole and since FtsZ shares functional homology with, β-tubulin it may also be sensitive to albendazole. Therefore, the effect of albendazole was tested against Wolbachia occurring in mosquitoes instead of filarial parasites as the drug has lethal effect on the latter. Third instar larvae of Culex quinquefasciatus were treated with 0.25 mg/ml of albendazole (test) or tetracycline (positive control) in the rearing medium for different intervals and tested for the presence of Wolbachia by FtsZ PCR. All the treated larvae were negative for the presence of the FtsZ band, whereas all the control larvae were positive. The findings of the study, thus indicated that FtsZ is sensitive to albendazole. In view of this albendazole appears to have dual targets; FtsZ in Wolbachia and β-tubulin in W. bancrofti. Further, the functional domain of the gene was assessed for polymorphism among recombinant clones representing 120 W. bancrofti parasites, prevalent across wide geographic areas of India and found to be highly conserved among them. Since it is highly conserved and plays an important role in Wolbachia cell division it appears to be a potential target for anti-filarial chemotherapy development.     

Deep intraspecific divergences in the medically relevant fat-tailed scorpions (Androctonus, Scorpiones)

The genus Androctonus, commonly known as fat-tailed scorpions, contains 22 species distributed from Togo and Mauritania in the west, North Africa, through the Middle East and to as far east as India. With 13 species, a substantial amount of this genus’ diversity occurs in North Africa, which is a major hotspot of scorpion sting incidents. Androctonus are among the most medically relevant animals in North Africa. Since venom composition within species is known to vary regionally, the improvement of therapeutic management depends on a correct assessment of the existing regional specific and sub-specific variation. In this study, we assessed the phylogeographical patterns in six species of Androctonus scorpions from North Africa using mitochondrial DNA markers. We sequenced COX1, 12S, 16S and ND1 genes from 110 individuals. Despite lacking basal resolution in the tree, we found taxonomical and geographically coherent clades. We discovered deep intraspecific variation in the widespread Androctonus amoreuxi and Androctonus australis, which consisted of several well-supported clades. Genetic distances between some of these clades are as high as those found between species. North African A. australis have a deep split in Tunisia around the Chott el-Djerid salt-lake. A novel split between A. amoreuxi scorpions was found in Morocco. We also found deep divergences in Androctonus mauritanicus, corresponding to areas attributed to invalidated subspecies. In addition we uncovered a clade of specimens from coastal south Morocco, which could not be ascribed to any know species using morphological characters. Based on these findings we recommend a reassessment of venom potency and anti-venom efficacy between these deep intraspecific divergent clades.     

Chewing lice (Phthiraptera) from Calidris fuscicollis (Aves: Scolopacidae) in Southern Brazil

During April and September from 2010 to 2012, 80 birds of the species Calidris fuscicollis (white-rumped sandpiper) were collected for parasitological studies in the southern coast of Rio Grande do Sul, under ICMBIO license No. 26234-1. For ectoparasite collection, the birds were first submerged in water with detergent. The parasites found were fixed in 70% alcohol, cleared in 10% potassium hydroxide and mounted in Canada balsam. Of 80 birds examined, 79% were parasitized. Actornithophilus umbrinus (47.5%), Actornithophilus lacustris (37.5%), Actornithophilus spp. (13.75%), Carduiceps zonarius (26.25%), Lunaceps incoenis (27.5%), and Lunaceps spp. (16.25%) were the species found with their respective prevalence. We record for the first time parasitism by chewing lice in Calidris fuscicollis.     

The Anopheles stephensi odorant binding protein 1 (AsteObp1) gene: A new molecular marker for biological forms diagnosis

Anopheles (Cellia) stephensi Liston 1901 is known as an Asian malaria vector. Three biological forms, namely “mysorensis”, “intermediate”, and “type” have been earlier reported in this species. Nevertheless, the present morphological and molecular information is insufficient to diagnose these forms. During this investigation, An. stephensi biological forms were morphologically identified and sequenced for odorant-binding protein 1 (Obp1) gene. Also, intron I sequences were used to construct phylogenetic trees. Despite nucleotide sequence variation in exon of AsteObp1, nearly 100% identity was observed at the amino acid level among the three biological forms. In order to overcome difficulties in using egg morphology characters, intron I sequences of An. stephensi Obp1 opens new molecular way to the identification of the main Asian malaria vector biological forms. However, multidisciplinary studies are needed to establish the taxonomic status of An. stephensi.     

Regulation of laboratory populations of snails (Biomphalaria and Bulinus spp.) by river prawns, Macrobrachium spp. (Decapoda,Palaemonidae): Implications for control of schistosomiasis

Human schistosomiasis is a common parasitic disease endemic in many tropical and subtropical countries. One barrier to achieving long-term control of this disease has been re-infection of treated patients when they swim, bathe, or wade in surface fresh water infested with snails that harbor and release larval parasites. Because some snail species are obligate intermediate hosts of schistosome parasites, removing snails may reduce parasitic larvae in the water, reducing re-infection risk. Here, we evaluate the potential for snail control by predatory freshwater prawns, Macrobrachium rosenbergii and M. vollenhovenii, native to Asia and Africa, respectively. Both prawn species are high value, protein-rich human food commodities, suggesting their cultivation may be beneficial in resource-poor settings where few other disease control options exist. In a series of predation trials in laboratory aquaria, we found both species to be voracious predators of schistosome-susceptible snails, hatchlings, and eggs, even in the presence of alternative food, with sustained average consumption rates of 12% of their body weight per day. Prawns showed a weak preference for Bulinus truncatus over Biomphalaria glabrata snails. Consumption rates were highly predictable based on the ratio of prawn: snail body mass, suggesting satiation-limited predation. Even the smallest prawns tested (0.5–2 g) caused snail recruitment failure, despite high snail fecundity. With the World Health Organization turning attention toward schistosomiasis elimination, native prawn cultivation may be a viable snail control strategy that offers a win–win for public health and economic development.     

Physa marmorata (Mollusca: Physidae) as a natural intermediate host of Trichobilharzia (Trematoda: Schistosomatidae), a potential causative agent of avian cercarial dermatitis in Brazil

Species of Trichobilharzia are the main etiological agents of cercarial dermatitis in humans, which is considered a re-emerging disease. Despite the diversity and global distribution of species of this genus, studies of Trichobilharzia are scarce in South America. The goal of our investigations is better understand the diversity, distribution and life cycle of avian schistosomes and their likely role in causing dermatitis in Brazil. As part of this effort, cercariae found in naturally infected Physa marmorata were identified by morphological and molecular (mitochondrial cox1, nuclear ITS1 and 28S gene regions) methods as Trichobilharzia sp. These cercariae are similar morphologically to T. jequitibaensis described previously from Brazil and similar genetically to the North American physid transmitted species T. querquedulae and T. physellae. This is the first report of a potential agent of cercarial dermatitis from naturally infected snails from Brazil and first molecular characterization of a South American species of Trichobilharzia. A discussion follows concerning the potential role of this species has in outbreaks of dermatitis in Brazil.     

Candida: epidemiología y factores de riesgo para especies no albicans

Introduction

Nosocomial fungal infections have increased significantly in the last decade. Candida detection in clinical specimens can mean either colonization or an infection which can be local (muguet) or invasive. Knowledge of the species helps in choosing the best treatment. The aims of this study were to determine the frequency and distribution of Candida species detected in clinical samples, to analyze the clinical characteristics of the involved population and to determine the risk factors for Candida non-albicans species.

Methods

Retrospective, observational. Period: 2006-2010. Inclusion criteria: all isolates of Candida in clinical specimens from patients hospitalized —at least 48 hours in a neurological center. We analyzed epidemiological characteristics, co morbidities, risk factors, factors associated with Candida non-albicans detection, antifungal treatment, development of adverse events and mortality.

Results

Candida spp. was isolated from 321 clinical specimens: 139 (43.3%) were C. albicans and 182 (56.7%) Candida non-albicans. The distribution of the sample was: urine 122 (Candida non-albicans 67.2%), airway 81, oropharynx 45 (C. albicans) and candidemia 40 (Candida non-albicans 75%). The most frequent co-morbidity was solid tumor (35.5%). The main risk factors were antibiotic therapy (85.5%), steroid therapy (61.7%) and in ICU at diagnosis (61.6%). The analysis of risk factors and the isolation of Candida non-albicans shows that chemotherapy, previous surgery, treatment with aminopenicillins, carbapenems and glycopeptides were statistically significant (P < .05). There is a trend in neutropenic patients (P = .055) and in ICU at diagnosis (P = .076). Overall survival was 71%.

Conclusions

Candida species distribution varies with the type of sample analyzed. Non-albicans species make up the majority of the isolates. The identification of the species involved per sample helps to optimize treatment. The high frequency of isolation of Candida in patients on steroids and antibiotics and admitted to ICU, is worth pointing out. Patients with previous surgery, treated with the aforementioned antibiotics or chemotherapy, could receive non-azole antifungals in the initial empirical treatment strategy.