scholarly journals First Report on the Prevalence and Subtype Distribution of Blastocystis sp. in Edible Marine Fish and Marine Mammals: A Large Scale-Study Conducted in Atlantic Northeast and on the Coasts of Northern France

2020 ◽  
Vol 8 (3) ◽  
pp. 460 ◽  
Author(s):  
Nausicaa Gantois ◽  
Angélique Lamot ◽  
Yuwalee Seesao ◽  
Colette Creusy ◽  
Luen-Luen Li ◽  
...  

Blastocystis is frequently identified in humans and animal hosts and exhibits a large genetic diversity with the identification of 17 subtypes (STs). Despite its zoonotic potential, its prevalence and ST distribution in edible marine fish and marine mammals remain unknown. A large-scale survey was thus conducted by screening 345 fish caught in Atlantic Northeast and 29 marine mammals stranded on the coasts of northern France for the presence of the parasite using real-time Polymerase Chain Reaction PCR. The prevalence of the parasite was about 3.5% in marine fish. These animals were mostly colonized by poikilotherm-derived isolates not identified in humans and corresponding to potential new STs, indicating that fish are natural hosts of Blastocystis. Marine fishes are also carriers of human STs and represent a likely limited source of zoonotic transmission. 13.8% of the marine mammals tested were colonized and 6 different STs were identified including 3 potential new STs. The risk of zoonotic transmission through marine mammals is insignificant due to the lack of repeated contact with humans. The present survey represents the first data regarding the prevalence and ST distribution of Blastocystis in marine fish and marine mammals and provides new insights into its genetic diversity, host range and transmission.

2019 ◽  
Vol 17 (1) ◽  
pp. e1004 ◽  
Author(s):  
Darko Jevremović ◽  
Aleksandar Leposavić ◽  
Svetlana A Paunović

Raspberry leaf blotch emaravirus (RLBV) is a recently characterised virus infecting raspberries reported in several European countries. RLBV causes yellow blotching, the distortion of leaf margins, and the twisting of raspberry leaves. For a long time, similar symptoms were attributed to the feeding damage caused by raspberry leaf and bud mite (Phyllocoptes gracilis). From 2014−2017, a large-scale survey was conducted in Serbia to investigate the degree of association of the observed symptoms with the RLBV infection. A total of 98 symptomatic and asymptomatic samples were collected from 30 locations. All collected samples were tested on the RLBV presence by reverse transcription and polymerase chain reaction (RT-PCR) using three sets of RNA-specific primers targeting RNA-1, RNA-3, and RNA-5 of the RLBV genome. RT-PCR analysis revealed high incidence of RLBV in tested samples (68.7%). RLBV was confirmed in raspberries ‘Fertödi Zamatos’, ‘Glen Ample’, ‘Meeker’, ‘Polana’, ‘Tulameen’ and ‘Willamette’. Twenty-one isolates were selected for sequencing the portion of the nucleocapsid (NC) gene. The nucleotide sequences of the isolates showed 93.2−100% identity. Phylogenetic analysis confirmed significant genetic variability of the Serbian RLBV isolates based on the nucleocapsid-encoding sequences and revealed the existence of two main clusters. Phylogenetic analysis of the 45 RLBV sequences from Finland, Slovakia, Scotland, and this study also confirmed the existence of two main clusters of isolates.


2021 ◽  
Vol 9 (1) ◽  
pp. 184
Author(s):  
Salma Khaled ◽  
Nausicaa Gantois ◽  
Aisha Ayoubi ◽  
Gaël Even ◽  
Manasi Sawant ◽  
...  

Molecular data concerning the prevalence and subtype (ST) distribution of the intestinal parasite Blastocystis sp. remain scarce in the Middle East. Accordingly, we performed the first molecular epidemiological survey ever conducted in the Syrian population. A total of 306 stool samples were collected from Syrian refugees living in 26 informal tented settlements (ITS) subjected or not to water, sanitation, and hygiene (WASH) interventions in North Lebanon, then screened for the presence of Blastocystis sp. by real-time polymerase chain reaction followed by subtyping. The overall prevalence of the parasite was shown to reach 63.7%. Blastocystis sp. colonization was not significantly associated with gender, age, symptomatic status, abdominal pain or diarrhea. In contrast, WASH intervention status of ITS was identified as a risk factor for infection. Among a total of 164 subtyped isolates, ST3 was predominant, followed by ST1, ST2, and ST10. No particular ST was reported to be associated with age, gender, symptomatic status, digestive disorders, or WASH intervention status of ITS. Intra-ST diversity of ST1 to ST3 was low suggesting large-scale anthroponotic transmission. Moreover, comparative analysis of ST1 to ST3 genotypes revealed that the circulation of the parasite between Syrian refugees and the host population was likely limited.


2020 ◽  
Vol 139 ◽  
pp. 161-174
Author(s):  
R Palmer ◽  
GTA Fleming ◽  
S Glaeser ◽  
T Semmler ◽  
A Flamm ◽  
...  

During 1992 and 1993, a bacterial disease occurred in a seawater Atlantic salmon Salmo salar farm, causing serious mortalities. The causative agent was subsequently named as Oceanivirga salmonicida, a member of the Leptotrichiaceae. Searches of 16S rRNA gene sequence databases have shown sequence similarities between O. salmonicida and uncultured bacterial clones from the digestive tracts of marine mammals. In the current study, oral samples were taken from stranded dolphins (common dolphin Delphinus delphis, striped dolphin Stenella coeruleoalba) and healthy harbour seals Phoca vitulina. A bacterium with growth characteristics consistent with O. salmonicida was isolated from a common dolphin. The isolate was confirmed as O. salmonicida, by comparisons to the type strain, using 16S rRNA gene, gyrB, groEL, and recA sequence analyses, average nucleotide identity analysis, and MALDI-TOF mass spectrometry. Metagenomic analysis indicated that the genus Oceanivirga represented a significant component of the oral bacterial microbiomes of the dolphins and seals. However, sequences consistent with O. salmonicida were only found in the dolphin samples. Analyses of marine mammal microbiome studies in the NCBI databases showed sequences consistent with O. salmonicida from the common dolphin, striped dolphin, bottlenose dolphin Tursiops truncatus, humpback whale Megaptera novaeangliae, and harbour seal. Sequences from marine environmental studies in the NCBI databases showed no sequences consistent with O. salmonicida. The findings suggest that several species of marine mammals are natural hosts of O. salmonicida.


Author(s):  
Alba Rey-Iglesia ◽  
Philippe Gaubert ◽  
Gonçalo Espregueira Themudo ◽  
Rosa Pires ◽  
Constanza De La Fuente ◽  
...  

Abstract The Mediterranean monk seal Monachus monachus is one of the most threatened marine mammals, with only 600–700 individuals restricted to three populations off the coast of Western Sahara and Madeira (North Atlantic) and between Greece and Turkey (eastern Mediterranean). Its original range was from the Black Sea (eastern Mediterranean) to Gambia (western African coast), but was drastically reduced by commercial hunting and human persecution since the early stages of marine exploitation. We here analyse 42 mitogenomes of Mediterranean monk seals, from across their present and historical geographic ranges to assess the species population dynamics over time. Our data show a decrease in genetic diversity in the last 200 years. Extant individuals presented an almost four-fold reduction in genetic diversity when compared to historical specimens. We also detect, for the first time, a clear segregation between the two North Atlantic populations, Madeira and Cabo Blanco, regardless of their geographical proximity. Moreover, we show the presence of historical gene-flow between the two water basins, the Atlantic Ocean and the Mediterranean Sea, and the presence of at least one extinct maternal lineage in the Mediterranean. Our work demonstrates the advantages of using full mitogenomes in phylogeographic and conservation genomic studies of threatened species.


Plant Disease ◽  
2019 ◽  
Vol 103 (6) ◽  
pp. 1309-1318 ◽  
Author(s):  
Lei Zhao ◽  
Wen Yang ◽  
Yuanle Zhang ◽  
Zhanmin Wu ◽  
Qiao-Chun Wang ◽  
...  

Kiwifruit (Actinidia spp.) is an economically substantial fruit crop with China the main producer. China is the primary source of wild kiwifruit and the largest producer of kiwifruit in terms of both production and planting area, and Shaanxi province is the largest kiwifruit producer in China. Previous studies reported presence of kiwifruit viruses in Actinidia chinensis. In this study, six viruses were identified in kiwifruit ‘Xuxiang’ (A. deliciosa) in Shaanxi, China. The incidence, distribution, and genetic diversity of these viruses were studied. The results showed that Actinidia virus A (AcVA), Actinidia virus B (AcVB), Actinidia chlorotic ringspot-associated virus (AcCRaV), cucumber mosaic virus (CMV), apple stem grooving virus (ASGV), and potato virus X (PVX) were the main viruses infecting Xuxiang kiwifruit in Shaanxi, China. Incidence of the various viruses with both single and multiple infection varied with different kiwifruit-growing counties. For single virus infection, the highest and the lowest numbers of samples infected were about 22 for AcCRaV and 0 for AcVB in Meixian out of 170 samples, 12 for AcVA and 0 for CMV in Zhouzhi out of 120 samples, 10 for AcVA and 0 for AcVB, AcCRaV, ASGV, PVX, and CMV in Yangling out of 70 samples, and 8 for AcCRaV and CMV and 0 for AcVA, AcVB, ASGV, and PVX in Hanzhong out of 80 samples, respectively. Samples which were multiply infected with two or more viruses were also detected. Analysis of the phylogenetic tree of these viruses showed some genetic variability in the AcVA, AcVB, and AcCRaV isolates of Shaanxi kiwifruit. There was no obvious molecular variation in the coat protein genes of ASGV, CMV, and PVX virus isolates from Shaanxi kiwifruit. The present study is the first large-scale survey of kiwifruit viruses in Shaanxi, China. To our knowledge, this is the first report of PVX infecting kiwifruit and the first report of molecular variability of AcVA, AcVB, and AcCRaV. These results provide important data for studying the genetic evolution of AcVA, AcVB, AcCRaV, ASGV, CMV, and PVX.


Author(s):  
Xénia Keighley ◽  
Maiken Hemme Bro‐Jørgensen ◽  
Hans Ahlgren ◽  
Paul Szpak ◽  
Marta Maria Ciucani ◽  
...  

Author(s):  
Frederik Juhl Jørgensen ◽  
Mathias Osmundsen

Abstract Can corrective information change citizens’ misperceptions about immigrants and subsequently lead to favorable immigration opinions? While prior studies from the USA document how corrections about the size of minority populations fail to change citizens’ immigration-related opinions, they do not examine how other facts that speak to immigrants’ cultural or economic dependency rates can influence immigration policy opinions. To extend earlier work, we conducted a large-scale survey experiment fielded to a nationally representative sample of Danes. We randomly expose participants to information about non-Western immigrants’ (1) welfare dependency rate, (2) crime rate, and (3) proportion of the total population. We find that participants update their factual beliefs in light of correct information, but reinterpret the information in a highly selective fashion, ultimately failing to change their policy preferences.


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