Your search found 7 records
1 Horwitz, P.; Wilcox, B. A. 2005. Parasites, ecosystems and sustainability: An ecological and complex systems perspective. International Journal for Parasitology, 35:725-732.
(Location: IWMI-HQ Call no: P 7574 Record No: H039128)
2 Boelee, Eline; Senzanje, A.; Munamati, M.; Parron, L.; Rodrigues, L.; Laamrani, Hammou; Cecchi, P. 2009. Water quality assessment. In Andreini, Marc; Schuetz, Tonya; Harrington, Larry (Eds.). Small reservoirs toolkit, theme 3: ecosystems and health. Colombo, Sri Lanka: CGIAR Challenge Program on Water and Food (CPWF); Colombo, Sri Lanka: International Water Management Institute (IWMI); Brasilia, DF, Brasil: Brazilian Agricultural Research Corporation (Embrapa Cerrados Center); Harare, Zimbabwe: University of Zimbabwe (UZ); Accra, Ghana: Ghana Water Research Institution (WRI); Delft, The Netherlands: Delft University of Technology (TUD); Stockholm, Sweden: Stockholm Environment Institute (SEI); Marseille, France: Institut de Recherche pour le Developpement (IRD); Bonn, Germany: Center for Development Research, University of Bonn; Ithaca, NY, USA: Cornell University. 13p.
(Location: IWMI HQ Call no: e-copy only Record No: H042670)
Some rural populations are dependent on small reservoirs for their water supply and are concerned about the quality of this water for direct consumption and other uses. Chemical and biological water quality measurements can be made to ascertain the suitability of water for different uses. Water “suitability” of course, depends on the use for which it is intended. This tool describes selected methods for assessing the suitability of reservoir water quality.
3 Gunawardena, S.; Karunaweera, N. D.; Ferreira, M. U.; Phone-Kyaw, M.; Pollack, R. J.; Alifrangis, M.; Rajakaruna, R. S.; Konradsen, F.; Amerasinghe, Priyanie H.; Schousboe, M. L.; Galappaththy, G. N. L.; Abeyasinghe, R. R.; Hartl, D. L.; Wirth, D. F. 2010. Geographic structure of Plasmodium vivax: microsatellite analysis of parasite populations from Sri Lanka, Myanmar, and Ethiopia. American Journal of Tropical Medicine and Hygiene, 82(2):235-242. [doi: https://doi.org/10.4269/ajtmh.2010.09-0588]
Genetic variation ; Plasmodium vivax ; Parasites ; Public health ; Waterborne diseases ; Malaria ; Satellite observation ; Analysis / Sri Lanka / Myanmar / Ethiopia
(Location: IWMI HQ Call no: e-copy only Record No: H044535)
(1.07 MB) (1.07MB)
Genetic diversity and population structure of Plasmodium vivax parasites can predict the origin and spread of novel variants within a population enabling population specific malaria control measures. We analyzed the genetic diversity and population structure of 425 P. vivax isolates from Sri Lanka, Myanmar, and Ethiopia using 12 trinucleotide and tetranucleotide microsatellite markers. All three parasite populations were highly polymorphic with 3–44 alleles per locus. Approximately 65% were multiple-clone infections. Mean genetic diversity ( H E ) was 0.7517 in Ethiopia, 0.8450 in Myanmar, and 0.8610 in Sri Lanka. Significant linkage disequilibrium was maintained. Population structure showed two clusters (Asian and African) according to geography and ancestry. Strong clustering of outbreak isolates from Sri Lanka and Ethiopia was observed. Predictive power of ancestry using two-thirds of the isolates as a model identified 78.2% of isolates accurately as being African or Asian. Microsatellite analysis is a useful tool for mapping short-term outbreaks of malaria and for predicting ancestry.
4 Jayawardena, U. A.; Tkach, V. V.; Navaratne, A. N.; Amerasinghe, Priyanie H.; Rajakaruna, R. S. 2013. Malformations and mortality in the Asian common toad induced by exposure to Pleurolophocercous cercariae (Trematoda: Cryptogonimidae). Parasitology International, 62:246-252. [doi: https://doi.org/10.1016/j.parint.2013.01.003]
(Location: IWMI HQ Call no: e-copy only Record No: H046260)
(0.58 MB)
Malformations and increased mortality due to infection by the digenetic trematode, Riberioa ondatrae have been reported for many species of amphibians. Severe malformations have also been reported in the Common Hourglass Tree Frog, Polypedates cruciger induced by Pleurolophocercous cercariae in Sri Lanka in addition to the changes in the behaviour, development and survival of the host. We exposed pre-limb bud stage tadpoles (Gosner stages 25–26) of the Asian Common Toad, Duttaphrynus melanostictus to the same pleurolophocercous type cercariae under laboratory conditions. Molecular and morphological identification showed that these cercariae belonged Acanthostomum burminis infecting freshwater snakes as definitive hosts. These cercariae induced malformations (27.8%) and reduced survival to metamorphosis (53.8%). The magnitude of the effects increased with the dose of cercariae. Types of malformations were mainly axial, such as scoliosis and kyphosis. Severe limb malformations such as extra or missing limbs as reported for amphibians exposed to R. ondatrae were not observed in the D. melanostictus. Same authors reported a higher percentage of malformations previously when P. cruciger was exposed to the cercariae A. burminis compared to D. melanostictus. However, tadpoles of D. melanostictus, which are smaller compared to those of P. cruciger, experienced higher mortality than P. cruciger tadpoles. Trematode induced malformations and mortality in amphibians are highly variable and depend on multiple factors such as host species differences such as resistance to infection and tolerance, life-history characteristics such as size at metamorphosis and length of the metamorphosis period, and other factors such as size of the amphibian at the time of trematode exposure.
5 Schousboe, M. L.; Ranjitkar, S.; Rajakaruna, R. S.; Amerasinghe, Priyanie; Konradsen, F.; Morales, F.; Ord, R.; Pearce, R.; Leslie, T.; Rowland, M.; Gadalla, N; Bygbjerg, C.; Alifrangis, M.; Roper, C. 2014. Global and local genetic diversity at two microsatellite loci in Plasmodium vivax parasites from Asia, Africa and South America. Malaria Journal, 13:1-9. [doi: https://doi.org/10.1186/1475-2875-13-392]
Genetic variation ; Plasmodium vivax ; Parasites ; Loci ; Malaria ; Public health ; Microsatellites / Asia / Africa / South America / Sri Lanka / Pakistan / Afghanistan / Nepal / Sudan / Venezuela / Ecuador
(Location: IWMI HQ Call no: e-copy only Record No: H047016)
http://www.malariajournal.com/content/pdf/1475-2875-13-392.pdf
https://vlibrary.iwmi.org/pdf/H047016.pdf
https://vlibrary.iwmi.org/pdf/H047016.pdf
(0.34 MB) (349 KB)
Background: Even though Plasmodium vivax has the widest worldwide distribution of the human malaria species and imposes a serious impact on global public health, the investigation of genetic diversity in this species has been limited in comparison to Plasmodium falciparum. Markers of genetic diversity are vital to the evaluation of drug and vaccine efficacy, tracking of P. vivax outbreaks, and assessing geographical differentiation between parasite populations.
Methods: The genetic diversity of eight P. vivax populations (n = 543) was investigated by using two microsatellites (MS), m1501 and m3502, chosen because of their seven and eight base-pair (bp) repeat lengths, respectively. These were compared with published data of the same loci from six other P. vivax populations.
Results: In total, 1,440 P. vivax samples from 14 countries on three continents were compared. There was highest heterozygosity within Asian populations, where expected heterozygosity (He) was 0.92-0.98, and alleles with a high repeat number were more common. Pairwise FST revealed significant differentiation between most P. vivax populations, with the highest divergence found between Asian and South American populations, yet the majority of the diversity (~89%) was found to exist within rather than between populations.
Conclusions: The MS markers used were informative in both global and local P. vivax population comparisons and their seven and eight bp repeat length facilitated population comparison using data from independent studies. A complex spatial pattern of MS polymorphisms among global P. vivax populations was observed which has potential utility in future epidemiological studies of the P. vivax parasite.
Methods: The genetic diversity of eight P. vivax populations (n = 543) was investigated by using two microsatellites (MS), m1501 and m3502, chosen because of their seven and eight base-pair (bp) repeat lengths, respectively. These were compared with published data of the same loci from six other P. vivax populations.
Results: In total, 1,440 P. vivax samples from 14 countries on three continents were compared. There was highest heterozygosity within Asian populations, where expected heterozygosity (He) was 0.92-0.98, and alleles with a high repeat number were more common. Pairwise FST revealed significant differentiation between most P. vivax populations, with the highest divergence found between Asian and South American populations, yet the majority of the diversity (~89%) was found to exist within rather than between populations.
Conclusions: The MS markers used were informative in both global and local P. vivax population comparisons and their seven and eight bp repeat length facilitated population comparison using data from independent studies. A complex spatial pattern of MS polymorphisms among global P. vivax populations was observed which has potential utility in future epidemiological studies of the P. vivax parasite.
6 Dickens, Chris; O’Brien, G.; Stassen, R.; Eriyagama, Nishadi; Kleynhans, M.; Rowntree, K.; Graham, M.; Ross-Gillespie, V.; MacKenzie, J.; Wymenga, E.; Mapedza, Everisto; Burnet, M.; Desai, M.; Hean, J. 2018. E-Flows for the Upper Niger River and Inner Niger Delta: specialist response report for vegetation, fish, invertebrates and birds. [Project report prepared by the International Water Management Institute for Wetlands International]. Colombo, Sri Lanka: International Water Management Institute (IWMI). CGIAR Research Program on Water, Land and Ecosystems (WLE). 104p.
Environmental flows ; Vegetation ; Fisheries ; Invertebrates ; Birds ; Ecosystem services ; Aquatic environment ; Habitats ; Biodiversity ; Rivers ; Deltas ; Living standards ; Public health ; Waterborne diseases ; Risk assessment ; Malaria ; Onchocerciasis ; Parasites ; Pathogens ; Vectors ; Sanitation ; Water resources ; Water quality ; Floodplains ; Sediment ; Modelling / West Africa / Upper Niger River / Inner Niger Delta
(Location: IWMI HQ Call no: e-copy only Record No: H049436)
(5.46 MB)
7 Kyei-Baafour, E.; Tornyigah, B.; Buade, B.; Bimi, L.; Oduro, A. R.; Koram, K. A.; Gyan, B. A.; Kusi, K. A. 2020. Impact of an irrigation dam on the transmission and diversity of Plasmodium falciparum in a seasonal malaria transmission area of northern Ghana. Journal of Tropical Medicine, 2020:1386587. [doi: https://doi.org/10.1155/2020/1386587]
Malaria ; Disease transmission ; Irrigation ; Dams ; Infectious diseases ; Parasites ; Plasmodium falciparum ; Dry season ; Wet season ; Communities / Ghana / Bongo
(Location: IWMI HQ Call no: e-copy only Record No: H049812)
http://downloads.hindawi.com/journals/jtm/2020/1386587.pdf
https://vlibrary.iwmi.org/pdf/H049812.pdf
https://vlibrary.iwmi.org/pdf/H049812.pdf
(1.27 MB) (1.27 MB)
Water bodies such as dams are known to alter the local transmission patterns of a number of infectious diseases, especially those transmitted by insects and other arthropod vectors. The impact of an irrigation dam on submicroscopic asexual parasite carriage in individuals living in a seasonal malaria transmission area of northern Ghana was investigated. A total of 288 archived DNA samples from two cross-sectional surveys in two communities in the Bongo District of Northern Ghana were analysed. Parasite density was determined by light microscopy and PCR, and parasite diversity was assessed by genotyping of the polymorphic Plasmodium falciparum msp2 block-3 region. Submicroscopic parasitaemia was estimated as the proportional difference between positive samples identified by PCR and microscopy. Dry season submicroscopic parasite prevalence was significantly higher (71.0%, ) at the dam site compared with the nondam site (49.2%). Similarly, wet season submicroscopic parasite prevalence was significantly higher at the dam site (54.5%, ) compared with the nondam site (33.0%). There was no difference in parasite density between sites in the dry season () and in the wet season (). Multiplicity of infection (MOI) based on PCR data was significantly higher at the dam site compared with the nondam site during the dry season () but similar between sites during the wet season. MOI at the nondam site was significantly higher in the wet season than in the dry season (2.49, 1.26, ) but similar between seasons at the dam site. Multivariate analysis showed higher odds of carrying submicroscopic parasites at the dam site in both dry season (OR = 7.46, 95% CI = 3.07–18.15) and in wet season (OR = 1.73, 95% CI = 1.04–2.86). The study findings suggest that large water bodies impact year-round carriage of submicroscopic parasites and sustain Plasmodium transmission.
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