scholarly journals Estimation of parasite infection prevalence of Joseon people by paleoparasitological data updates from the ancient feces of pre-modern Korean mummies

2017 ◽  
Vol 125 (1) ◽  
pp. 9-14 ◽  
Author(s):  
MIN SEO ◽  
CHANG SEOK OH ◽  
JONG HA HONG ◽  
JONG-YIL CHAI ◽  
SOON CHUL CHA ◽  
...  
Keyword(s):  
Parasite Infection ◽  
Infection Prevalence

scholarly journals Modelling to explore the potential impact of asymptomatic human infections on transmission and dynamics of African sleeping sickness

2021 ◽  
Vol 17 (9) ◽  
pp. e1009367
Author(s):  
Maryam Aliee ◽  
Matt J. Keeling ◽  
Kat S. Rock
Keyword(s):  
Neglected Tropical Diseases ◽  
Asymptomatic Infection ◽  
Parasite Infection ◽  
Human Infection ◽  
Sleeping Sickness ◽  
Blood Parasites ◽  
Transmission Model ◽  
Infection Prevalence ◽  
Symptomatic Infection ◽  
Detection Rates

Gambiense human African trypanosomiasis (gHAT, sleeping sickness) is one of several neglected tropical diseases (NTDs) where there is evidence of asymptomatic human infection but there is uncertainty of the role it plays in transmission and maintenance. To explore possible consequences of asymptomatic infections, particularly in the context of elimination of transmission—a goal set to be achieved by 2030—we propose a novel dynamic transmission model to account for the asymptomatic population. This extends an established framework, basing infection progression on a number of experimental and observation gHAT studies. Asymptomatic gHAT infections include those in people with blood-dwelling trypanosomes, but no discernible symptoms, or those with parasites only detectable in skin. Given current protocols, asymptomatic infection with blood parasites may be diagnosed and treated, based on observable parasitaemia, in contrast to many other diseases for which treatment (and/or diagnosis) may be based on symptomatic infection. We construct a model in which exposed people can either progress to either asymptomatic skin-only parasite infection, which would not be diagnosed through active screening algorithms, or blood-parasite infection, which is likely to be diagnosed if tested. We add extra parameters to the baseline model including different self-cure, recovery, transmission and detection rates for skin-only or blood infections. Performing sensitivity analysis suggests all the new parameters introduced in the asymptomatic model can impact the infection dynamics substantially. Among them, the proportion of exposures resulting in initial skin or blood infection appears the most influential parameter. For some plausible parameterisations, an initial fall in infection prevalence due to interventions could subsequently stagnate even under continued screening due to the formation of a new, lower endemic equilibrium. Excluding this scenario, our results still highlight the possibility for asymptomatic infection to slow down progress towards elimination of transmission. Location-specific model fitting will be needed to determine if and where this could pose a threat.

scholarly journals Blood Parasite Infection Prevalence in Kampong Chicken Breeder’s Group in Garut

2017 ◽  
Vol 3 (6) ◽  
pp. 308
Author(s):  
Djoko Legowo ◽  
Syifa Husnul Khotimah ◽  
Lucia Tri Suwanti
Keyword(s):  
Parasite Infection ◽  
Blood Parasite ◽  
Blood Parasites ◽  
Infection Prevalence ◽  
Blood Samples ◽  
Negative Results

The Aim of this research was to determine the blood parasite infection prevalence in Garut District. The research was conducted in November-December 2016. 160 samples of blood were obtained from eight subdistrict at Kampong Chicken Breeder’s Group (KEPAK) in Garut District smeared with 3% Giemsa solution and examined under a microscope with 1000x magnification. The merozoite and gametocyte that was discovered recorded. The data that obtained was analyzed descriptively. A parasites were found in 11 blood samples (6.88%). The genus of blood parasites is Leucocytozoon sp., while Plasmodium sp., Haemoproteus sp., and Trypanosoma avium sp. are not found in this research (0%). All of blood infected parasite only found at Tarogong Kidul subdistrict and seven other subdistricts showed negative results.  Keyword: Blood parasite, Leucocytozoon, KEPAK, Kampong Chicken

Blood parasite infection linked to condition of spring-migrating Lesser Scaup (Aythya affinis)

2018 ◽  
Vol 96 (10) ◽  
pp. 1145-1152 ◽  
Author(s):  
L. Merrill ◽  
J.M. Levengood ◽  
J.C. England ◽  
J.M. Osborn ◽  
H.M. Hagy
Keyword(s):  
Body Fat ◽  
Reproductive Output ◽  
Parasite Infection ◽  
Malaria Vectors ◽  
Infection Prevalence ◽  
Haemosporidian Parasite ◽  
Aythya Affinis ◽  
Lesser Scaup ◽  
Haemosporidian Parasites ◽  
The Impact

Numerous organisms exhibit carry-over effects, in which previous environmental conditions impact current performance. For example, reproductive output for many migratory birds can be impacted by events during the preceding migration. Lesser Scaup (Aythya affinis (Eyton, 1838); hereafter scaup) declined dramatically during 1970s–2000s, and there is evidence linking reduced reproductive output to reduced body condition during spring migration. In addition to food availability and quality, haemosporidian parasites (Plasmodium spp., Haemoproteus spp.) may be associated with condition of spring-migrating birds. We examined whether haemosporidian parasite infection status was linked to measures of size (mass, wing length, tarsus length, and keel length) and condition (body fat, size-corrected mass, wing-loading) in female spring-migrating scaup. Infection prevalence varied by year (21.7% in 2014; 47.1% in 2015) and percent body fat was negatively associated with the probability of infection. Body fat levels declined from 2014 to 2015, but at a similar rate for infected and uninfected birds. This pattern suggests that the increased prevalence in 2015 may have been related to the greater proportion of poor-condition birds being more susceptible to infection or recrudescence of latent infections. In light of forecasted range shifts and expansions of avian malaria vectors, the impact of haemosporidian parasites on migratory waterfowl condition warrants further investigation.

scholarly journals Responses of an oyster host (Crassostrea virginica) and its protozoan parasite (Perkinsus marinus) to increasing air temperature

PeerJ ◽  
2018 ◽  
Vol 6 ◽  
pp. e5046 ◽  
Author(s):  
Jennafer C. Malek ◽  
James E. Byers
Keyword(s):  
Immune Response ◽  
Crassostrea Virginica ◽  
Air Temperature ◽  
Infection Intensity ◽  
Protozoan Parasite ◽  
Parasite Infection ◽  
Infection Prevalence ◽  
Perkinsus Marinus ◽  
Air Temperatures ◽  
Average Maximum

Background Changes in climate are predicted to influence parasite and pathogen infection patterns in terrestrial and marine environments. Increases in temperature in particular may greatly alter biological processes, such as host-parasite interactions. For example, parasites could differentially benefit from increased reproduction and transmission or hosts could benefit from elevated immune responses that may mediate or even eliminate infections. In the southeastern United States, the Eastern oyster, Crassostrea virginica, is infected by the lethal protozoan parasite, Perkinsus marinus. Under field conditions, intertidal (air-exposed) oysters have been found to have significantly higher P. marinus infection intensity and marginally higher infection prevalence than subtidal (submerged) oysters. During summer, air temperatures are much warmer than water and this exposure of intertidal oysters to higher temperatures is a suggested mechanism for increased infection intensity. Methods We simulated intertidal exposure using controlled laboratory experiments to determine how host traits (survival and immune response) and parasite infection intensity will respond to elevated air temperature ranging from 27 °C to 53 °C during emersion at low tide. In Georgia, where our work was conducted, the average summer water temperature is 29 °C and the average maximum high air temperature in July is 33 °C (though oysters have been shown to survive at much higher air temperatures). Results Host survival declined as temperature increased, with a definitive drop-off between 39–43 °C. Negative effects of air temperature on host immune response (phagocytic activity) were detectable only at extremely high temperatures (47–50 °C) when hosts were suffering acute mortality. Parasite infection intensity peaked at 35 °C. Discussion Our results suggest that an increase in average summer air temperature to 35 °C or higher could affect oyster survival directly through temperature-related impacts in the short-term and indirectly through increased P. marinus infection intensity over the long-term.

scholarly journals Modelling to explore the potential impact of asymptomatic human infections on transmission and dynamics of African sleeping sickness

2021 ◽  
Author(s):  
Maryam Aliee ◽  
Matt J Keeling ◽  
Kat S Rock
Keyword(s):  
Neglected Tropical Diseases ◽  
Asymptomatic Infection ◽  
Parasite Infection ◽  
Human Infection ◽  
Sleeping Sickness ◽  
Blood Parasites ◽  
Transmission Model ◽  
Infection Prevalence ◽  
Symptomatic Infection ◽  
Detection Rates

Gambiense human African trypanosomiasis (gHAT, sleeping sickness) is one of several neglected tropical diseases (NTDs) where there is evidence of asymptomatic human infection but there is uncertainty of the role it plays in transmission and maintenance. To explore possible consequences of asymptomatic infections, particularly in the context of elimination of transmission, a goal set to be achieved by 2030, we propose a novel dynamic transmission model to account for the asymptomatic population. This extends an established framework, basing infection progression on a number of experimental and observation gHAT studies. Asymptomatic gHAT infections include those in people with blood-dwelling trypanosomes, but no discernible symptoms, or those with parasites only detectable in skin. Given current protocols, asymptomatic infection with blood parasites may be diagnosed and treated, based on observable parasitaemia, in contrast to many other diseases for which treatment (and/or diagnosis) may be based on symptomatic infection. We construct a model in which exposed people can either progress to either asymptomatic skin-only parasite infection, which would not be diagnosed through active screening algorithms, or blood-parasite infection, which is likely to be diagnosed if tested. We add extra parameters to the baseline model including different self-cure, recovery, transmission and detection rates for skin-only or blood infections. Performing sensitivity analysis suggests all the new parameters introduced in the asymptomatic model can impact the infection dynamics substantially. Among them, the proportion of exposures resulting in initial skin or blood infection appears the most influential parameter. For some plausible parameterisations, an initial fall in infection prevalence due to interventions could subsequently stagnate even under continued screening due to the formation of a new, lower endemic equilibrium. Excluding this scenario, our results still highlight the possibility for asymptomatic infection to slow down progress towards elimination of transmission. Location-specific model fitting will be needed to determine if and where this could pose a threat.

Interactions among four parasite species in an amphipod population from Patagonia

2012 ◽  
Vol 87 (1) ◽  
pp. 97-101 ◽  
Author(s):  
C.A. Rauque ◽  
L. Semenas
Keyword(s):  
Life Cycle ◽  
Food Intake ◽  
Parasite Species ◽  
Positive Association ◽  
Host Population ◽  
Parasite Infection ◽  
Infection Prevalence ◽  
Mean Intensity ◽  
Larval Stages ◽  
High Infection

AbstractParasites commonly share their hosts with specimens of the same or different parasite species, resulting in multiple parasites obtaining resources from the same host. This could potentially lead to conflicts between co-infecting parasites, especially at high infection intensities. In Pool Los Juncos (Patagonia, Argentina), the amphipodHyalella patagonicais an intermediate host to three parasites that mature in birds (the acanthocephalanPseudocorynosomasp. and larval stages of two Cyclophyllidea cestodes), in addition to a microsporidian (Thelohaniasp.), whose life cycle is unknown, but very likely to be monoxenous. The aim of this study was to describe interactions between these parasite species in their amphipod host population. Amphipods were collected monthly between June 2002 and January 2004 to assess parasite infection. Infection prevalence and mean intensity were greatest in larger male amphipods for all parasite species. We also found a positive association betweenThelohaniasp. and bothPseudocorynosomasp. and Cyclophyllidea sp. 1 infections, thoughPseudocorynosomasp. and Cyclophyllidea sp. 1 were negatively associated with each other. We conclude that contrasting associations between parasite species may be associated with competition for both food intake and space in the haemocoel.

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