37 research outputs found
Achatina (Lissachatina) fulica Bowdich: its molecular phylogeny, genetic variation in global populations, and its possible role in the spread of the rat lungworm Angiostrongylus cantonensis (CHEN)
The Giant African Snail, Achatina (Lissachatina) fulica Bowdich, is a tropical crop pest species with a widespread distribution across East Africa, the Indian subcontinent, Southeast Asia, the Pacific and the Caribbean. It is also a known intermediate host of the rat lungworm, Angiostrongylus cantonensis, which can infect humans and cause eosinophilic meningitis. The phylogenetic position of A. fulica within the Achatinoidea and the Achatinidae was investigated using segments of the nuclear ribosomal (r) RNA cluster, actin and histone 3 genes and the mitochondrial CO1 and 16S rRNA genes. Results from molecular data support the monophyly of the Achatinidae based on the taxa surveyed as well as the morphological distinction of the Eastern Achatina (Lissachatina) from the Western and Central Achatina (Achatina); Lissachatina should therefore be elevated to genus status. The results also show non-monophyly of the Coeliaxidae, Ferussaciidae and Subulinidae; the taxonomy of these families must therefore be reassessed. The extent of genetic diversity in global A. fulica populations was also determined using an SSCP molecular marker developed from the 16S rRNA gene. Results reveal only one haplotype (C) emerged from East Africa and spread globally. The rat lungworm (Angiostrongylus cantonensis) has a parallel distribution with A. fulica, and the possible role of the snail in the spread of the parasite is investigated using a molecular marker derived from the small subunit (SSU) rRNA gene. A survey of the parasite within the route of dispersal of A. fulica detected A. cantonensis only in the Philippines and the French Polynesian territory of Tahiti, the latter of which being the first reported case of A. cantonensis infection for Achatina fulica in that territory. Due to the limited sampling of the snail and the patchy distribution of the parasite, there are insufficient data at this time to assess the role of Achatina fulica in the spread of Angiostrongylus cantonensis
Philippine Survey of Nematode Parasite Infection and Load in the Giant African Snail Achatina fulica indicate Angiostrongylus cantonensis infection in Mindanao
Achatina fulica is a ubiquitous land snail commonly found throughout the Philippines. As a generalist feeder and being able to survive in a wide range of habitat types and conditions, the snail can easily establish itself in a new area after introduction. It also acts as host to a variety of parasites, including nematodes, which may accidentally infect humans. In this study, A. fulica individuals from 13 areas in the Philippines were sampled and analyzed for nematode infection rate and load. Of the 393 individuals sampled, 80 (20%) were found to be infected, with 5049 nematodes isolated. The infection rates and parasite load were highly variable. Overall, the parasite load ranges from 1 to 867 per snail. Representative nematodes from A. fulica from Plaridel (n=8) and Davao City (n=26) in Mindanao were subjected to DNA extraction, PCR amplification, and sequencing of the SSU rRNA gene, which is the universal barcode for nematodes. Sequences successfully matched with the dog lungworm Oslerus osleri for the Plaridel nematodes and the rat lungworm Angiostrongylus cantonensis for the Davao City nematodes, respectively. The latter is known to infect humans and can cause eosinophilic meningoencephalitis. This study presents the first report of A. cantonensis in A. fulica from Mindanao and raises a public health concern
Achatina (Lissachatina) fulica Bowdich : its molecular phylogeny, genetic variation in global populations, and its possible role in the spread of the rat lungworm Angiostrongylus cantonensis (CHEN)
The Giant African Snail, Achatina (Lissachatina) fulica Bowdich, is a tropical crop pest species with a widespread distribution across East Africa, the Indian subcontinent, Southeast Asia, the Pacific and the Caribbean. It is also a known intermediate host of the rat lungworm, Angiostrongylus cantonensis, which can infect humans and cause eosinophilic meningitis. The phylogenetic position of A. fulica within the Achatinoidea and the Achatinidae was investigated using segments of the nuclear ribosomal (r) RNA cluster, actin and histone 3 genes and the mitochondrial CO1 and 16S rRNA genes. Results from molecular data support the monophyly of the Achatinidae based on the taxa surveyed as well as the morphological distinction of the Eastern Achatina (Lissachatina) from the Western and Central Achatina (Achatina); Lissachatina should therefore be elevated to genus status. The results also show non-monophyly of the Coeliaxidae, Ferussaciidae and Subulinidae; the taxonomy of these families must therefore be reassessed. The extent of genetic diversity in global A. fulica populations was also determined using an SSCP molecular marker developed from the 16S rRNA gene. Results reveal only one haplotype (C) emerged from East Africa and spread globally. The rat lungworm (Angiostrongylus cantonensis) has a parallel distribution with A. fulica, and the possible role of the snail in the spread of the parasite is investigated using a molecular marker derived from the small subunit (SSU) rRNA gene. A survey of the parasite within the route of dispersal of A. fulica detected A. cantonensis only in the Philippines and the French Polynesian territory of Tahiti, the latter of which being the first reported case of A. cantonensis infection for Achatina fulica in that territory. Due to the limited sampling of the snail and the patchy distribution of the parasite, there are insufficient data at this time to assess the role of Achatina fulica in the spread of Angiostrongylus cantonensis.EThOS - Electronic Theses Online ServiceGBUnited Kingdo
Optimizing the Utility of Allium cepa L. var. aggregatum (sibuyas Tagalog) for the Allium Test by Elucidating its Mitotic Periodicity and Rhythmicity Under Varying Light Conditions
The occurrence of pattern of mitotic activity has long been studied in different plants; in the onion Allium cepa, determination of its mitotic activity has led to its utilization in the Allium test for cytotoxicity and mutagenicity of test substances. In this study, the pattern of mitotic activity of A. cepa var. aggregatum and the effect of light exposure on mitotic activity were determined to test the utility of A. cepa L. var. aggregatum as an alternative to the common onion, A. cepa, for the Allium test. Bulblets of A. cepa var. aggregatum were allowed to root for three days in tap water under three different set-ups: constant light exposure set-up (Light), constant dark set-up (Dark) and 12 hours light-12 hours dark set-up (Light-Dark). The root tips from the bulblets were then excised and subjected to microscopic observation for the mitotic index (MI) every hour after the third day. The results showed no significant difference observed across the three set-ups. However, MI for the Dark and Light set-ups were periodic, showing peaks or maxima of MI falling between 11 AM and 12 PM, whereas that of Light-Dark set-up was rhythmic, having an hourly fluctuation, but also showed maximum between 11 AM and 12 PM. It is recommended that A. cepa var. aggregatum root tips be excised between 11 AM and 12 PM for the Allium test
Whole mitochondrial genome of a Geoffroy’s Rousette, Rousettus amplexicaudatus (Pteropodidae)
The whole mitochondrial genome assembly of Rousettus amplexicaudatus belonging to the Pteropodidae found in the Philippines was sequenced and characterised. De novo sequence assembly yielded a 16,509bp sequence with an overall base composition of 32.43% A, 25.39% T, 26.17% C, and 14.02% G. The mitochondrial genome is composed 22 tRNA genes, 13 protein-coding genes, and two rRNA genes. Molecular phylogeny of the order Chiroptera based on the maximum likelihood and Bayesian inference trees supports the classification of R. amplexicaudatus to genus Rousettus and family Pteropodidae. Furthermore, both trees support the modern division of order Chiroptera into the Yinpterochiroptera and Yangochiroptera clades
Vectors and Spatial Patterns of Angiostrongylus cantonensis
In the Philippines, rats and snails abound in agricultural areas as pests and source of food for some of the local people which poses risks of parasite transmission to humans such as Angiostrongylus cantonensis. This study was conducted to determine the extent of A. cantonensis infection among rats and snails collected from rice-farming villages of Muñoz, Nueva Ecija. A total of 209 rats, 781 freshwater snails, and 120 terrestrial snails were collected for the study. Heart and lungs of rats and snail tissues were examined and subjected to artificial digestion for parasite collection. Adult worms from rats were identified using SSU rDNA gene. Seven nematode sequences obtained matched A. cantonensis. Results revealed that 31% of the rats examined were positive with A. cantonensis. Rattus norvegicus and R. tanezumi showed prevalence of 46% and 29%, respectively. Furthermore, only Pomacea canaliculata (2%) and Melanoides maculata (1%) were found to be positive for A. cantonensis among the snails collected. Analysis of host distribution showed overlapping habitats of rats and snails as well as residential and agricultural areas indicating risks to public health. This study presents a possible route of human infection for A. cantonensis through handling and consumption of P. canaliculata and M. maculata or crops contaminated by these snails
SpecimenData
Voucher info, Taxonomy, Specimen Details and Collection Data of the fishes collected in Taal Lake, Philippine
Odds, challenges and new approaches in the control of helminthiasis, an Asian study
The time is passing, and the worms are still a major struggle for local people in Asian countries, especially the less empowered and in a situation of social vulnerability. We are working in the field in Laos, Thailand, and the Philippines where the usual control programs based only on human treatment are partially effective. Areas with mass drug administration could diminish, but not eliminate STHs of endemic areas. The persistence of helminthic NTDs in the environment and animal hosts makes the eradication a very difficult task. Great changes in the landscapes of endemic areas, such as construction of dams, can change the fauna and the lifestyle of local people. Those changes can improve infrastructure, but it can also lead to social vulnerability. The challenge, then, is to conceive new and directed control programs for helminthiasis based on multi- and transdisciplinary approaches diminishing the health gap in a globalized world. In this short review, we summarize the actual scenario concerning the main helminths in Southeast Asia and how an environmental DNA approach and the use of GIS could contribute to surveillance and control programs. Keywords: Neglected tropical diseases, Worms, Social vulnerability, Environmental DNA, GIS, One-health, Ecohealt
consensus sequences
Consensus sequences of the COI barcodes of the fishes collected in Taal Lake, Philippine
ImageData
Standard lengths, BOLD process ID of the fishes collected in Taal Lake, Philippine