Studies of host preferences of wild-caught Phlebotomus orientalis and Ph. papatasi vectors of leishmaniasis in Sudan

Ditylenchus dipsaci, the stem nematode, is a migratory endoparasite of over 500 species of angiosperms. The main method of D. dipsaci control is crop rotation, but the presence of morphologically indistinguishable host races with different host preferences makes rotation generally ineffective. Therefore, a sensitive, rapid, reliable, as well as cost effective technique is needed for identification of D. dipsaci in biological samples. This study describes the development of species-specific pairs of PCR oligonucleotides for detection and identification of the D. dipsaci stem nematode in various plant hosts. Designed DIT-2 primer pair specifically amplified a fragment of 325 bp, while DIT-5 primer pair always produced a fragment of 245 bp in all D. dipsaci isolates. Two developed SCAR primer pairs were further tested using template DNA extracted from a collection of twelve healthy plant hosts; no amplification was however observed. The developed PCR protocol has proved to be quite sensitive and able to specifically detect D. dipsaci in artificially infested plant tissues.

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On a new Temnocephala (Platyhelminthes) from Southern Patagonia (Chile, Argentina), with a redescription of T. chilensis and some systematic and biogeographical insights

Zootaxa ◽

10.11646/zootaxa.4853.3.9 ◽

2020 ◽

Vol 4852 (3) ◽

pp. 383-395

Author(s):

RODRIGO PONCE DE LEÓN ◽

ERICH H. RUDOLPH ◽

ODILE VOLONTERIO

Keyword(s):

New Species ◽

Geographic Distribution ◽

Southern Chile ◽

Host Preferences ◽

Southern Patagonia ◽

Diagnostic Key ◽

A New Species

To date, only one species of Temnocephala is known from Chile, Temnocephala chilensis, and three from southern Argentina (Patagonia), namely T. chilensis, Temnocephala dionii, and Temnocephala mexicana. Here we describe a new species of Temnocephala and provide an updated description of T. chilensis based on material found on an anomuran crab (Aeglidae) from southern Chile. Additional hosts and localities are reported for both species in southern Argentina and Chile, and a diagnostic key for all species of Temnocephala hosted on Aegla and Parastacidae is included as well. In southern Chile, both T. chilensis and the new species were found on the crayfish Samastacus spinifrons and on the anomuran crabs Aegla abtao and Aegla alacalufi; in addition, the new species was found on Aegla manni, and T. chilensis on Aegla rostrata. In southern Argentina, T. chilensis and the new species were found on Aegla riolimayana and S. spinifrons. Based on their shared traits (morphology of the penial stylet, host preferences and geographic distribution), the temnocephalans hosted in Aegla are tentatively gathered into two clusters, the Chilensis and Axenos groups.

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The growing repertoire of genetic tools for dissecting chlamydial pathogenesis

Pathogens and Disease ◽

10.1093/femspd/ftab025 ◽

2021 ◽

Author(s):

Arkaprabha Banerjee ◽

David E Nelson

Keyword(s):

Genetic Engineering ◽

Intracellular Bacteria ◽

Human Pathogens ◽

Pathogenic Potential ◽

Host Preferences ◽

Genetic Tools ◽

Obligate Intracellular ◽

Obligate Intracellular Bacteria ◽

Multiple Species

Abstract Multiple species of obligate intracellular bacteria in the genus Chlamydia are important veterinary and/or human pathogens. These pathogens all share similar biphasic developmental cycles and transition between intracellular vegetative reticulate bodies and infectious elementary forms, but vary substantially in their host preferences and pathogenic potential. A lack of tools for genetic engineering of these organisms has long been an impediment to the study of their biology and pathogenesis. However, the refinement of approaches developed in C. trachomatis over the last ten years, and adaptation of some of these approaches to other Chlamydia spp. in just the last few years, has opened exciting new possibilities for studying this ubiquitous group of important pathogens.

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Evolving Patterns of Cryptosporidiosis: Issues and Implications in the Context of Public Health in India

Annals of the National Academy of Medical Sciences (India) ◽

10.1055/s-0041-1726149 ◽

2021 ◽

Author(s):

Bijay Ranjan Mirdha

Keyword(s):

Public Health ◽

Genetic Diversity ◽

Genetic Recombination ◽

Acute Infection ◽

Transmission Intensity ◽

Future Research ◽

Cryptosporidium Hominis ◽

Host Preferences ◽

Childhood Growth ◽

Life Years

AbstractCryptosporidiosis is one of the major causes of diarrhea in immune-compromised individuals and children besides causing sporadic water-borne, food-borne, and zoonotic outbreaks. In 2016, Cryptosporidium species infection was the fifth leading cause of diarrhea and acute infection causing more than 4.2 million disability-adjusted life years lost besides a decrease in childhood growth. Human cryptosporidiosis is primarily caused by two species/genotype: Cryptosporidium hominis (anthroponotic) and Cryptosporidium parvum (zoonotic) besides other six rare species/genotypes. Transmission intensity, genetic diversity, and occurrence of genetic recombination have shaped the genus Cryptosporidium population structures into palmitic, clonal, and epidemic. Genetic recombination is more in C. parvum compared with C. hominis. Furthermore, parasite–host co-evolution, host adaptation, and geographic segregation have led to the formation of “subtype- families.” Host-adapted subtype-families have distinct geographical distribution and host preferences. Genetic exchanges between subtypes played an important role throughout the evolution of the genus leading to “adaptation introgression” that led to emergence of virulent and hyper-transmissible subtypes. The population structure of C. hominis in India appears to be more complex where both transmission intensity and genetic diversity are much higher. Further, study based on “molecular strain surveillance” has resulted newer insights into the epidemiology and transmission of cryptosporidiosis in India. The identification at the species and genotype levels is essential for the assessment of infection sources in humans and the public health potential of the parasite at large. The results of the study over three decades on cryptosporidiosis in India, in the absence of a national surveillance data, were analyzed highlighting current situation on epidemiology, genetic diversity, and distribution particularly among vulnerable population. Despite creditable efforts, there are still many areas need to be explored; therefore, the intent of this article is to facilitate future research approaches for mitigating the burden associated with this disease.

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Host preferences of PalaearcticCulicoidesbiting midges: implications for transmission of orbiviruses

Medical and Veterinary Entomology ◽

10.1111/j.1365-2915.2012.01042.x ◽

2012 ◽

Vol 27 (3) ◽

pp. 255-266 ◽

Cited By ~ 42

Author(s):

E. VIENNET ◽

C. GARROS ◽

L. GARDÈS ◽

I. RAKOTOARIVONY ◽

X. ALLÈNE ◽

...

Keyword(s):

Host Preferences

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Phlebotomus orientalis Sand Flies from Two Geographically Distant Ethiopian Localities: Biology, Genetic Analyses and Susceptibility to Leishmania donovani

PLoS Neglected Tropical Diseases ◽

10.1371/journal.pntd.0002187 ◽

2013 ◽

Vol 7 (4) ◽

pp. e2187 ◽

Cited By ~ 33

Author(s):

Veronika Seblova ◽

Vera Volfova ◽

Vit Dvorak ◽

Katerina Pruzinova ◽

Jan Votypka ◽

...

Keyword(s):

Leishmania Donovani ◽

Sand Flies ◽

Genetic Analyses ◽

Phlebotomus Orientalis

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Host preferences of low-trunk vascular epiphytes in a cloud forest of Veracruz, Mexico

Journal of Tropical Ecology ◽

10.1017/s0266467405002683 ◽

2005 ◽

Vol 21 (6) ◽

pp. 651-660 ◽

Cited By ~ 46

Author(s):

Klaus Mehltreter ◽

Alejandro Flores-Palacios ◽

José G. García-Franco

Keyword(s):

Water Retention ◽

Cloud Forest ◽

Water Retention Capacity ◽

Retention Capacity ◽

Host Preferences ◽

Host Group ◽

Vascular Epiphytes ◽

Lower Trunk ◽

Tree Ferns ◽

Epiphyte Species

The diversity, abundance and frequency of vascular epiphytes on the lower trunk were compared between two host groups of a Mexican cloud forest: angiosperm trees (n = 72) and tree ferns (n = 28). The bark of the five most frequent host trees and the root mantle of the two tree ferns were analysed for their thickness, water content, water retention capacity and pH. A total of 55 epiphyte species and 910 individuals were found on the 27 host species. On hosts with a dbh range of 5–10 cm, epiphytes were significantly more diverse (4.3±0.9 species per host) and more abundant (12.5±2.2 individuals per host) on tree ferns than on angiosperm trees (1.9±0.2 species per host and 3.9±0.6 individuals per host). However, these differences were not significant for the dbh class of 10–20 cm, because epiphyte numbers increased on angiosperm trees with larger host size, but not in tree ferns. Most epiphyte species had no preference for any host group, but four species were significantly more frequent on tree ferns and two species on angiosperm trees. The higher epiphyte diversity and abundance on tree fern trunks of the smallest dbh class is attributed to their presumably greater age and to two stem characteristics, which differed significantly between host groups, the thicker root mantle and higher water retention capacity of tree ferns. These bark characteristics may favour germination and establishment of epiphytes.

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