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Background: Malaria is still a priority public health problem of Nepal where about 84% of the population are at risk. The aim of this paper is to highlight the past and present malaria situation in this country and its challenges for long-term malaria elimination strategies.
Methods: Malariometric indicator data of Nepal recorded through routine surveillance of health facilities for the years between 1963 and 2012 were compiled. Trends and differences in malaria indicator data were analysed.
Results: The trend of confirmed malaria cases in Nepal between 1963 and 2012 shows fluctuation, with a peak in 1985 when the number exceeded 42,321, representing the highest malaria case-load ever recorded in Nepal. This was followed by a steep declining trend of malaria with some major outbreaks. Nepal has made significant progress in controlling malaria transmission over the past decade: total confirmed malaria cases declined by 84% (12,750 in 2002 vs 2,092 in 2012), and there was only one reported death in 2012. Based on the evaluation of the National Malaria Control Programme in 2010, Nepal recently adopted a long-term malaria elimination strategy for the years 2011–2026 with the ambitious vision of a malaria-free Nepal by 2026. However, there has been an increasing trend of Plasmodium falciparum and imported malaria proportions in the last decade. Furthermore, the analysis of malariometric indicators of 31 malaria-risk districts between 2004 and 2012 shows a statistically significant reduction in the incidence of confirmed malaria and of Plasmodium vivax, but not in the incidence of P. falciparum and clinically suspected malaria.
Conclusions: Based on the achievements the country has made over the last decade, Nepal is preparing to move towards malaria elimination by 2026. However, considerable challenges lie ahead. These include especially, the need to improve access to diagnostic facilities to confirm clinically suspected cases and their treatment, the development of resistance in parasites and vectors, climate change, and increasing numbers of imported cases from a porous border with India. Therefore, caution is needed before the country embarks towards malaria elimination.
In the absence of an active prophylactic vaccine against HIV-1, passively administered, broadly neutralizing antibodies (bnAbs) identified in some chronically infected persons were shown to prevent HIV-1 infection in animal models. However, passive administration of bnAbs may not be suited to prevent sexual HIV-1 transmission in high-risk cohorts, as a continuous high level of active bnAbs may be difficult to achieve at the primary site of sexual transmission, the human vagina with its acidic pH. Therefore, we used Lactobacillus, a natural commensal in the healthy vaginal microbiome, to express bn nanobodies (VHH) against HIV-1 that we reported previously. After demonstrating that recombinant VHHA6 expressed in E. coli was able to protect humanized mice from mucosal infection by HIV-1Bal, we expressed VHHA6 in a soluble or in a cell-wall-anchored form in Lactobacillus rhamnosus DSM14870. This strain is already clinically applied for treatment of bacterial vaginosis. Both forms of VHHA6 neutralized a set of primary epidemiologically relevant HIV-1 strains in vitro. Furthermore, VHHA6 was still active at an acidic pH. Thus, lactobacilli expressing bn VHH potentially represent an attractive vector for the passive immunization of women in cohorts at high risk of HIV-1 transmission.
Bartonellae are facultative intracellular alpha-proteobacteria often transmitted by arthropods. Ixodes ricinus is the most important vector for arthropod-borne pathogens in Europe. However, its vector competence for Bartonella spp. is still unclear. This study aimed to experimentally compare its vector competence for three Bartonella species: B. henselae, B. grahamii, and B. schoenbuchensis. A total of 1333 ticks (1021 nymphs and 312 adults) were separated into four groups, one for each pathogen and a negative control group. Ticks were fed artificially with bovine blood spiked with the respective Bartonella species. DNA was extracted from selected ticks to verify Bartonella-infection by PCR. DNA of Bartonella spp. was detected in 34% of nymphs and females after feeding. The best engorgement results were obtained by ticks fed with B. henselae-spiked blood (65.3%) and B. schoenbuchensis (61.6%). Significantly more nymphs fed on infected blood (37.3%) molted into adults compared to the control group (11.4%). Bartonella DNA was found in 22% of eggs laid by previously infected females and in 8.6% of adults molted from infected nymphs. The transovarial and transstadial transmission of bartonellae suggest that I. ricinus could be a potential vector for three bacteria.
Leptoconops Skuse and Culicoides Latreille (Diptera: Ceratopogonidae) biting midges are serious pests of mammals, birds, and reptiles and important vectors of viruses, protozoans, and filarial nematodes. Their collection became an important adjunct to mosquito surveillance using light-baited and CO2-baited suction traps in Grand County, Utah, United States, during 1999–2016. During 2017–2020, collecting was expanded to California, Nevada, Idaho, Wyoming, Colorado, Arizona, New Mexico, and other parts of Utah using an ultraviolet light suction trap. As a result, five species of Leptoconops and 59 species of Culicoides, representing Leptoconops subgenera Holoconops Kieffer and Leptoconops Skuse, Culicoides subgenera Amossovia Glukhova, Beltranmyia Vargas, Diphaomyia Vargas, Drymodesmyia Vargas, Haematomyidium Goeldi, Monoculicoides Khalaf, Selfia Khalaf, Sensiculicoides Shevchenko, Silvaticulicoides Glukhova, Silvicola Mirzaeva and Isaev, and Wirthomyia Vargas, and the Culicoides Leoni, Limai, Palmerae, Piliferus, Saundersi, and Stonei species groups, were collected. Keys to adult males and females and tables of diagnostic characters are provided for identification of 15 species of Leptoconops and 86 species of Culicoides collected, reported by others, or likely to occur in the Southwestern United states west of the Continental Divide. Description references, synonymies, diagnoses, geographic and seasonal distributions, and biological summaries from the available literature are provided. Data on relative abundance in light-baited or CO2-baited traps are provided for the species collected. Intersex specimens and specimens parasitized by mites or mermithid nematodes are tabulated. Culicoides (Drymodesmyia) bakeri Vargas is reported from California (new United States record). New state records of other species for Idaho, Nevada, Utah, Colorado, Arizona, and New Mexico of the United States and for the Mexico states of Puebla, San Luis Potosi, and Oaxaca are reported. Culicoides salihi Khalaf is assigned to the subgenus Diphaomyia of Culicoides (new status). Culicoides stellifer (Coquillett) is reassigned to the subgenus Haematomyidium of Culicoides (new status). Culicoides travisi Vargas is assigned to the subgenus Sensiculicoides of Culicoides (new status). Culicoides luglani Jones and Wirth is reassigned to the Culicoides Limai group (new status). Confusion over species limits was evident between Culicoides cacticola Wirth and Hubert and Culicoides torridus Wirth and Hubert, between C. travisi and Culicoides kibunensis Tokunaga, between Culicoides doeringae Atchley and Culicoides lophortygis Atchley and Wirth, between Culicoides owyheensis Jones and Wirth and Culicoides mortivallis Wirth and Blanton, and between Culicoides cockerellii (Coquillett), Culicoides neomontanus Wirth, and Culicoides sierrensis Wirth and Blanton. Several new species, hybrids, or variants of Culicoides are diagnosed but not formally described: two of subgenus Silvicola, one of the Palmerae group, two of the Piliferus group, and one unplaced to subgenus or species group.
ZooBank registration. urn:lsid:zoobank.org:pub:CBD29188-143B-44DF-BE21-1654D50D8621
Impacts of alien species on human health have recently become a major issue in medical research and invasion ecology, but comprehensive assessments of this subject are largely lacking. Here, we provide a literature review of alien species with public health impacts in Europe based on a systematic search in the Thomson Reuters Web of Science. We detected 77 relevant articles, of which 21 were reviews and 56 were original research articles. The taxonomic focus was on vascular plants (n=31 articles) and dipterans (n=25 articles). The original research articles mainly covered the spread of the study species, while early invasion stages (introduction, establishment) as well as impact and management were less investigated. Alien species of health concern in Europe are mostly introduced as contaminants, and mostly originate from climatically similar regions of the Northern Hemisphere. In those cases (36% of all articles) when information on the trend in range and abundance was provided, this trend was mostly increasing. We detected little information on the severity of the impacts (two articles) and the interaction with climate change (three articles). In 15 original articles (28%) specific management measures were suggested, in only one article the socioeconomic costs were assessed. We conclude that European research on human health impacts of alien species is biased towards few species, and that several important aspects such as early invasion stages, severity of impact and its temporal trends, and the scale of the socioeconomic costs caused are poorly understood. Interdisciplinary projects bridging gaps between ecologists medical researchers, socioeconomists and public health authorities are required to link alien species to severity and trends of impacts, which is a crucial requisite for risk assessment and decision making.
Despite advances in bioinformatics, custom scripts remain a source of difficulty, slowing workflow development and hampering reproducibility. Here, we introduce Vectools, a command-line tool-suite to reduce reliance on custom scripts and improve reproducibility by offering a wide range of common easy-to-use functions for table and vector manipulation. Vectools also offers a number of vector related functions to speed up workflow development, such as simple machine learning and common statistics functions.
Despite advances in bioinformatics, custom scripts remain a source of difficulty, slowing workflow development and hampering reproducibility. Here, we introduce Vectools, a command-line tool-suite to reduce reliance on custom scripts and improve reproducibility by offering a wide range of common easy-to-use functions for table and vector manipulation. Vectools also offers a number of vector related functions to speed up workflow development, such as simple machine learning and common statistics functions.