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Prevalence Of Tick Borne Encephalitis Virus In Tick Nymphs In Relation To Climatic Factors On The Southern Coast Of Norway, Torstein Tengs Dr.

Dr. Torstein Tengs

BACKGROUND

Tick-borne encephalitis (TBE) is among the most important vector borne diseases of humans in Europe and is currently identified as a major health problem in many countries. TBE endemic zones have expanded over the past two decades, as well as the number of reported cases within endemic areas. Multiple factors are ascribed for the increased incidence of TBE, including climatic change. The number of TBE cases has also increased in Norway over the past decade, and the human cases cluster along the southern coast of Norway. In Norway the distribution and prevalence of TBE virus (TBEV) in tick populations …

A Quantitative Taqman Mgb Real-Time Polymerase Chain Reaction Based Assay For Detection Of The Causative Agent Of Crayfish Plague Aphanomyces Astaci, Torstein Tengs

Dr. Torstein Tengs

Here we present the development and first validation of a TaqMan minor groove binder (MGB) real-time polymerase chain reaction (RT-PCR) method for quantitative and highly specific detection of Aphanomyces astaci, the causative agent of crayfish plague. The assay specificity was experimentally assessed by testing against DNA representative of closely related oomycetes, and theoretically assessed by additional sequence similarity analyses comparing the primers and probe sequences to available sequences in EMBL/GenBank. The target of the assay is a 59 bp unique sequence motif of A. astaci found in the internal transcribed spacer 1 of the nuclear ribosomal gene cluster. A standard …

Development Of Real–Time Pcr Assays For The Detection Of Chattonella Species In Culture And Environmental Samples, Torstein Tengs

Dr. Torstein Tengs

Raphidophytes have been associated with fish kill events in Japanese, European and U.S. coastal waters, and many produce toxins that can pose a threat to human health. The recognition of raphidophytes as HAB species in mid-Atlantic estuarine waters led us to initiate molecular phylogenetic analyses of these taxa and to develop real-time PCR assays for rapid detection of important species. The molecular studies and PCR detection methods will enhance ongoing taxonomic, toxicologic and ecological of these organisms and will be a useful tool in HAB monitoring programs.

Use Of Molecular Probes To Assess Geographic Distribution Of Pfiesteria Species, Torstein Tengs

Dr. Torstein Tengs

We have developed multiple polymerase chain reaction (PCR)-based methods for the detection of Pfiesteria sp. in cultures and environmental samples. More than 2,100 water and sediment samples from estuarine sites of the U.S. Atlantic and gulf coasts were assayed for the presence of Pfiesteria piscicida Steidinger & Burkholder and Pfiesteria shumwayae Glasgow & Burkholder by PCR probing of extracted DNA. Positive results were found in about 3% of samples derived from routine monitoring of coastal waters and about 8% of sediments. The geographic range of both species was the same, ranging from New York to Texas. Pfiesteria spp. are likely …

Genetic Polymorphism In Gymnodinium Galatheanum Chloroplast Dna Sequences And Development Of A Molecular Detection Assay, Torstein Tengs

Dr. Torstein Tengs

Nuclear and chloroplast-encoded small subunit ribosomal DNA sequences were obtained from several strains of the toxic dinoflagellate Gymnodinium galatheanum . Phylogenetic analyses and comparison of sequences indicate that the chloroplast sequences show a higher degree of sequence divergence than the nuclear homologue. The chloroplast sequences were chosen as targets for the development of a 5'–3' exonuclease assay for detection of the organism. The assay has a very high degree of specificity and has been used to screen environmental water samples from a fish farm where the presence of this dinoflagellate species has previously been associated with fish kills. Various hypotheses …

Real–Time Pcr Monitoring Of Estuarine Water Samples For Pfiesteria Piscicida, A Dinoflagellate Associated With Fish Kills And Human Illness, Torstein Tengs

Dr. Torstein Tengs

No abstract.

Development Of Real-Time Pcr Assays For Rapid Detection Of Pfiesteria Piscicida And Related Dinoflagellates, Torstein Tengs

Dr. Torstein Tengs

Pfiesteria complex species are heterotrophic and mixotrophic dinoflagellates that have been recognized as harmful algal bloom species associated with adverse fish and human health effects along the East Coast of North America, particularly in its largest (Chesapeake Bay in Maryland) and second largest (Albermarle- Pamlico Sound in North Carolina) estuaries. In response to impacts on human health and the economy, monitoring programs to detect the organism have been implemented in affected areas. However, until recently, specific identification of the two toxic species known thus far, Pfiesteria piscicida and P. shumwayae (sp. nov.), required scanning electron microscopy (SEM). SEM is a …