Longitudinal analysis on parasite diversity in honeybee colonies: new taxa, high frequency of mixed infections and seasonal patterns of variation

Seventeen species of helminths were found in 134 voles of 5 species (Phenacomys intermedius, Clethrionomys gapperi, Microtus longicaudus, Microtus montanus, Microtus pennsylvanicus) collected in 1964 and 1965 in western Montana. Ten new records for North America and 26 new records for Montana were recorded. Seasonal patterns of infection were noted in Quinqueserialis quinqueserialis and Paranoplocephala infrequens. The taxonomy of the nematode Heligmosomum dubius (Baylis, 1926) Tenora, 1958 was discussed. The first record of Aspiculuris tetraptera in. microitne rodents and the second record of Pelodera sp. in the orbits of North American rodents were reported. A high frequency of mixed infections of the digestive tract was found, usually accompanied by a pronounced stratification of the helminths within the tract.

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Multiple STL decomposition in discovering a multi-seasonality of intraday trading volume

Croatian Operational Research Review ◽

10.17535/crorr.2021.0006 ◽

2021 ◽

Vol 12 (1) ◽

pp. 61-74

Author(s):

Josip Arneric

Keyword(s):

High Frequency ◽

Trading Volume ◽

Missing Values ◽

High Frequency Data ◽

Seasonal Patterns ◽

Time Varying ◽

Frequency Data ◽

Seasonal Component ◽

Univariate Time Series ◽

Over Time

The seasonal and trend decomposition of a univariate time-series based on Loess (STL) has several advantages over traditional methods. It deals with any periodicity length, enables seasonality change over time, allows missing values, and is robust to outliers. However, it does not handle trading day variation by default. This study offers how to deal with this drawback. By applying multiple STL decompositions of 15-minute trading volume observations, three seasonal patterns were discovered: hourly, daily, and monthly. The research objective was not only to discover if multi-seasonality exists in trading volume by employing high-frequency data but also to determine which seasonal component is most time-varying, and which seasonal components are the strongest or weakest when comparing the variation in the magnitude between them. The results indicate that hourly seasonality is the strongest, while daily seasonality changes the most. A better understanding of trading volume multiple patterns can be very helpful in improving the performance of trading algorithms.

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Trypanosoma cruzi:Study of the Distribution of Two Widespread Clonal Genotypes in BolivianTriatoma infestansVectors Shows a High Frequency of Mixed Infections

Experimental Parasitology ◽

10.1006/expr.1996.0075 ◽

1996 ◽

Vol 83 (3) ◽

pp. 275-282 ◽

Cited By ~ 34

Author(s):

Marie-France Bosseno ◽

Jenny Telleria ◽

Fernando Vargas ◽

Nina Yaksic ◽

François Noireau ◽

...

Keyword(s):

High Frequency ◽

Mixed Infections

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Characterization of Rotavirus Strains in a Danish Population: High Frequency of Mixed Infections and Diversity within the VP4 Gene of P[8] Strains

Journal of Clinical Microbiology ◽

10.1128/jcm.43.3.1099-1104.2005 ◽

2005 ◽

Vol 43 (3) ◽

pp. 1099-1104 ◽

Cited By ~ 25

Author(s):

T. K. Fischer ◽

J. Eugen-Olsen ◽

A. G. Pedersen ◽

K. Molbak ◽

B. Bottiger ◽

...

Keyword(s):

High Frequency ◽

Mixed Infections ◽

Danish Population

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Cestode parasites (Neodermata, Platyhelminthes) from Malaysian birds, with description of five new species

European Journal of Taxonomy ◽

10.5852/ejt.2020.616 ◽

2020 ◽

Author(s):

Jean Mariaux ◽

Boyko B. Georgiev

Keyword(s):

New Species ◽

New Taxa ◽

Field Trip ◽

Forest Birds ◽

Parasite Diversity ◽

Global Prevalence ◽

The World ◽

Small Collection ◽

Wild Hosts

We studied the cestode fauna (Platyhelminthes) of forest birds in Malaysia (Selangor) collected during a field trip in 2010. Ninety birds of 37 species were examined and global prevalence of cestodes was 15.3%. Five new taxa are described: Emberizotaenia aeschlii sp. nov. (Dilepididae) from Tricholestes criniger (Blyth, 1845) (Pycnonotidae); Anonchotaenia kornyushini sp. nov. (Paruterinidae) from Trichastoma malaccense (Hartlaub, 1844) (Pellorneidae); Biuterina jensenae sp. nov. (Paruterinidae) from Chloropsis cochinchinensis (Gmelin, 1789) (Irenidae); Raillietina hymenolepidoides sp. nov. (Davaineidae) and R. mahnerti sp. nov. (Davaineidae) from Chalcophaps indica (Linnaeus, 1758) (Columbidae). Ophryocotyloides dasi Tandan & Singh, 1964 is reported from Psilopogon henricii (Temminck, 1831) (Ramphastidae). Several other taxa in Dilepididae, Davaineidae, Paruterinidae, Hymenolepididae and Mesocestoididae, either potentially new or poorly known, are also reported. The richness described from this small collection hints at the potentially huge unknown parasite diversity from wild hosts in this part of the world.

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Suitability of current typing procedures to identify epidemiologically linked human Giardia duodenalis isolates

PLoS Neglected Tropical Diseases ◽

10.1371/journal.pntd.0009277 ◽

2021 ◽

Vol 15 (3) ◽

pp. e0009277

Author(s):

Andreas Woschke ◽

Mirko Faber ◽

Klaus Stark ◽

Martha Holtfreter ◽

Frank Mockenhaupt ◽

...

Keyword(s):

Primary Care ◽

High Frequency ◽

Giardia Duodenalis ◽

Multiple Infections ◽

Mixed Infections ◽

Single Strain ◽

Allelic Sequence ◽

Mlst Type ◽

Result Interpretation ◽

Assemblage B

Background Giardia duodenalis is a leading cause of gastroenteritis worldwide. Humans are mainly infected by two different subtypes, i.e., assemblage A and B. Genotyping is hampered by allelic sequence heterozygosity (ASH) mainly in assemblage B, and by occurrence of mixed infections. Here we assessed the suitability of current genotyping protocols of G. duodenalis for epidemiological applications such as molecular tracing of transmission chains. Methodology/Principal findings Two G. duodenalis isolate collections, from an outpatient tropical medicine clinic and from several primary care laboratories, were characterized by assemblage-specific qPCR (TIF, CATH gene loci) and a common multi locus sequence typing (MLST; TPI, BG, GDH gene loci). Assemblage A isolates were further typed at additional loci (HCMP22547, CID1, RHP26, HCMP6372, DIS3, NEK15411). Of 175/202 (86.6%) patients the G. duodenalis assemblage could be identified: Assemblages A 25/175 (14.3%), B 115/175 (65.7%) and A+B mixed 35/175 (20.0%). By incorporating allelic sequence heterozygosity in the analysis, the three marker MLST correctly identified 6/ 9 (66,7%) and 4/5 (80.0%) consecutive samples from chronic assemblage B infections in the two collections, respectively, and identified a cluster of five independent patients carrying assemblage B parasites of identical MLST type. Extended MLST for assemblage A altogether identified 5/6 (83,3%) consecutive samples from chronic assemblage A infections and 15 novel genotypes. Based on the observed A+B mixed infections it is estimated that only 75% and 50% of assemblage A or B only cases represent single strain infections, respectively. We demonstrate that typing results are consistent with this prediction. Conclusions/Significance Typing of assemblage A and B isolates with resolution for epidemiological applications is possible but requires separate genotyping protocols. The high frequency of multiple infections and their impact on typing results are findings with immediate consequences for result interpretation in this field.

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Cryptosporidium in fish: alternative sequencing approaches and analyses at multiple loci to resolve mixed infections

Parasitology ◽

10.1017/s0031182017001214 ◽

2017 ◽

Vol 144 (13) ◽

pp. 1811-1820 ◽

Cited By ~ 9

Author(s):

ANDREA PAPARINI ◽

RONGCHANG YANG ◽

LINDA CHEN ◽

KAISING TONG ◽

SUSAN GIBSON-KUEH ◽

...

Keyword(s):

Genetic Diversity ◽

High Frequency ◽

Sanger Sequencing ◽

Multiple Infections ◽

Mixed Infections ◽

Multiple Loci ◽

The Rich ◽

Next Generation Sequencing Ngs ◽

Molecular Parasitology ◽

Generation Sequencing

SUMMARYCurrently, the systematics, biology and epidemiology of piscine Cryptosporidium species are poorly understood. Here, we compared Sanger ‒ and next-generation ‒ sequencing (NGS), of piscine Cryptosporidium, at the 18S rRNA and actin genes. The hosts comprised 11 ornamental fish species, spanning four orders and eight families. The objectives were: to (i) confirm the rich genetic diversity of the parasite and the high frequency of mixed infections; and (ii) explore the potential of NGS in the presence of complex genetic mixtures. By Sanger sequencing, four main genotypes were obtained at the actin locus, while for the 18S locus, seven genotypes were identified. At both loci, NGS revealed frequent mixed infections, consisting of one highly dominant variant plus substantially rarer genotypes. Both sequencing methods detected novel Cryptosporidium genotypes at both loci, including a novel and highly abundant actin genotype that was identified by both Sanger sequencing and NGS. Importantly, this genotype accounted for 68·9% of all NGS reads from all samples (249 585/362 372). The present study confirms that aquarium fish can harbour a large and unexplored Cryptosporidium genetic diversity. Although commonly used in molecular parasitology studies, nested PCR prevents quantitative comparisons and thwarts the advantages of NGS, when this latter approach is used to investigate multiple infections.

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