Prevalence Of Parasites Research Articles

Endohelminth diversity in the invasive Clarias gariepinus (Burchell, 1822) from two freshwater lakes: Naivasha and Ol'Bolossat, Kenya.

Fish parasitology contributes to our understanding of the potential risks posed by diverse groups of parasitic organisms on fish stocks in either wild and culture systems. This study was conducted in May 2023 and aimed at assessing the diversity of endohelminths in the invasive North African catfish Clarias gariepinus (Burchell, 1822) obtained from two freshwater lakes, Naivasha and Ol'Bolossat, in Kenya. Parasitological examination of 66 and 35 fish samples collected from the two lakes respectively was achieved using light and scanning electron microscopy methods. Results revealed endohelminth diversity broadly classified as four digeneans, two nematodes, and one cestode. Seven taxa of endohelminths were found in C. gariepinus samples, but only four of these taxa could be identified up to the species level. Six of the taxa (Diplostomum sp., Tylodelphys mashonense, Plagiorchioidea sp., Paracamallanus cyathopharynx, Contracaecum sp., and Tetracampos ciliotheca) were common in samples from the two lakes. Glossidium pedatum only occurred in samples from Lake Ol'Bolossat. Parasite prevalence ranged from 8.6 (T. mashonense) to 100% (Diplostomum sp., T. ciliotheca, and Contracaecum sp.) and mean intensity from 1.4 (T. mashonense) to 16.9 (Diplostomum sp.). The diversity and richness indices were comparatively higher in fish samples from Lake Ol'Bolossat and attributed to the occurrence of G. pedatum in the Ol'Bolossat. However, parasitic infestation of fish samples from the two lakes depicted close similarity, both in diversity and prevalence. These findings form an important baseline data for further follow-up studies, and they suggest the need for further molecular analyses to fully describe three of the taxa only identified up to the genus level.

Prevalence of Gastrointestinal Parasites of African Catfish (Clarias gariepinus) from River Nasarawa, Nasarawa State, Nigeria

Fish and fish products are significant sources of nutrients for humans. Parasites of fish are of concern since they often produce a weakening of the host’s immunity thereby increasing susceptibility to secondary infections. This study was conducted with aimed to examine the prevalence of gastrointestinal parasites infecting fish. Field study was conducted during the period from September to November 2022. A total of 200 fish samples (Clarias gariepinus) were examined for the presence of gastrointestinal parasites. Result show that, total number of fishes infected 60(30.0%) out of which 26(26.26%) males and 34(33.66) female. Two helminths one each from Cestode and Nematode were isolated from the infected fishes. The Cestode and its prevalence were Diphylobothrium latum (5%) and nematode Procamallanus spp. (3.33%). The protozoa recovered included: Hexamita spp., Protoopalina spp. and Microsporidia with 60.00%, 23.33% and 18.34% respectively. The majority of the parasites were found in the intestine. Fish specimens that were lighter in weight 10 -200g had less infection (12.5%) but those found with parasites weighed between 201-400g (42%). There was no significant difference (P>0.05) in the infection between male and female Clarias gariepinus and with age on the prevalence and intensity of the gastrointestinal parasite. Wild fish (Clarias gariepinus) in River Nasarawa have a high prevalence of intestinal parasites, therefore it is recommended to avoid open defecation that finally is washed down to rivers and streams hence affecting the aquatic organisms and to properly cook wild fish obtained from River Nasarawa before consumption for safety.

Prevalence of Gastrointestinal Parasites among Student of Nasarawa State University, Keffi Nasarawa State, Nigeria

Gastrointestinal parasites are significant agents of intestinal infection with public health implications worldwide. This study aimed to ascertain intestinal parasites among students of Nasarawa State University, Keffi, Nasarawa State. A total of 138 Stool samples were collected from students in hostels and off campus and examined using the direct wet preparation and formol-ether concentration techniques. The overall prevalence of 18.84% was recorded with a higher prevalence of gastrointestinal parasites in samples collected from male subjects (23.61%) compared to the female individuals (13.63%) however, there was no statically significant difference (P>0.05) in prevalence between males and females subjects. The intestinal parasites species identified and their respective prevalence were: two species of nematodes; hookworm (26.92%) and Ascaris lumbricoides (46.15), a species of cestode- Taenia saginata (15.38%) and trematode- Schistosoma mansoni (11.58%). Gastrointestinal parasitic infection was higher in male hostel (50.00%) followed by female hostel (13.46%) and the least was recorded from the student village that is those students who live off campus (11.58%) although statistically, there is no significant difference between the location (P>0.05). The study showed that there is a high prevalence of gastrointestinal parasites in the study area (especially male hostel) therefore, there is a need to encourage adequate personal hygiene and sanitation. Also, further study should be carried out on the impact of parasitic infection on academic performance of the students.

<b> </b>SEASONAL<b> </b>VARIATION AND PREVALENCE OF GASTROINTESTINAL PARASITES IN CAPTIVE MAMMALS AT LAHORE ZOO

This study was conducted at Lahore Zoo, Punjab, Pakistan from January to December 2023 to assess the prevalence of gastrointestinal parasites in 10 different captive wild mammalian species. The mammals including girrafe (Giraffa), vervet monkey (Chlorocebus pygerythrus), zebra (Equus quagga), lion (Panthera leo), leopard (Panthera pardus), Rhinoceros (Rhinocerotidae), wild boar (Sus scrofa), Chinkara deer (Gazella bennettii), urial (Ovis vignei) and nilgai (Boselaphus tragocamelus) were selected. A total of 100 fresh fecal samples were collected from the animal enclosures in polythene bags (6×4 inches) 2 times during study period. Coprological examination was done using qualitative analysis such as direct smear method, sedimentation method and flotation methods. The parasitic prevalence was as follows zebra 44.5%, followed by giraffes, rhinoceroses, and wild boars at 27.8%, nilgai, urial, lion and vervet monkey at 22.3%, chinkara 16.7% and leopard 11.2%. The prevalence of gastrointestinal parasites was as Eimeria spp. (3.9%), Strongyloides spp. (3.4%), Trichuris spp. (2.8%), Giardia spp., Ascaris spp., and Strongyle spp. (2.3%), Entamoeba histolytica (1.12%), Trematode eggs (1.12%), Nematodirus (1.12%), Balantidium coli (0.6%), Haemonchus contortus (0.6%), Paramphistomum cervi (0.6%), Parascaris equorum (1.12%) and Cryptosporidium (1.12%). The overall parasitic prevalence was 23.9%, with a noticeable seasonal variation, being higher in summer (31.2%) compared to winter (17.79%). These findings highlight the significant parasitic burden in captive wild mammals. It can be concluded that regular de-worming sessions, cleaning, disinfection of enclosures and proper disposal of fecal matter should be done to reduce the overall parasitic burden.

Zoonotic parasite contamination of some green, leafy and spicy vegetables sold in major markets of Makurdi metropolis, Benue state

Consumption of contaminated vegetables can result in parasite ingestion with subsequent health problems. The spread of zoonotic parasites through contaminated vegetables is a complicated problem that requires attention to ensure food safety and protect public health. This study investigated the zoonotic parasitic contamination of some green, leafy, and spicy vegetables sold in Makurdi metropolis, Benue State. A cross-sectional study was designed in which four hundred green, leafy, and spicy vegetables consisting of five different vegetables, were collected from five markets in Makurdi town, Benue state. Sediments obtained by washing the vegetables with normal saline were centrifuged at 1500 rpm for five minutes before being subjected to flotation, sedimentation, and modified Ziehl-Neelsen techniques, and viewed under the microscope at various magnifications. The overall prevalence of zoonotic parasites was 59.75%. Strongyloides spp. larvae (40.5%), Cryptosporidium spp. Oocyst (0.5%), Balantidium coli cyst and trophozoite (7%), Ascaris spp (5.75%), Taenia spp. (9%), Strongyle ova (4.5%), and Giardia lamblia cyst (1.5%) were identified. Results showed a significant relationship between vegetable type and parasite contamination of vegetables (p < 0.05), but no significant relationship between market location and parasite contamination (p > 0.05). The high prevalence of zoonotic parasites observed in this study highlights the potential health risks associated with consuming contaminated vegetables. The study recommends public enlightenment of vegetable sellers and consumers in Makurdi on the importance of hand hygiene and safe handling of vegetables to prevent exposure to pathogenic microorganisms.

A Study on the Effect of Housing on Parasitic Load of Nellore Lambs

A study was carried out to find out the effect of housing on Parasitic load of Nellore Jodipi lambs under tropical environmental conditions. Thirty weaned Nellore ram lambs of 3-4 months age were selected based on body weight and randomly divided into three groups of ten animals each. The parasitic load i.e., Egg per gram (EPG) was determined regularly at every month during entire study period. The faecal egg count was performed by a Mc Master technique. With regard to parasitic load, the prevalence of parasites and eggs per gram (EPG) count were significantly (P<0.05) lower in slatted floor housing system (11.3±3.14) than that of morum floor housing systems (25.6±3.98 and 25.5±3.80). It was concluded that the housing system of elevated slatted flooring with galvalume roofing proved to be effective in controlling reinfestation of parasites and maintain hygiene environment for better performance of Nellore ram lambs.

Prevalence of gastrointestinal helminth parasites of cattle in Kugiya Market, Bukuru, Jos South LGA, Plateau State, Nigeria

Gastrointestinal helminth infection in cattle caused by trematodes (flukes), cestodes (tapeworms), and nematodes (roundworms) causes significant diseases which may result to growth retardation and significant economic damage. An investigation of gastrointestinal parasites of cattle sold at Kugiya market Bukuru, Jos South LGA was carried out between January and April 2016. Faecal samples of 232 cattle were examined using floatation method (Saturated Salt Solution). All the samples had gastrointestinal parasites. Nineteen 19(100%) species of gastrointestinal parasites were encountered, 2(3.88%) of which are protozoans, while the remaining 17(96.12%) were helminths as follows: 5(17.67%) trematodes (including 1 amphistome), 1(12.07%) cestode and 11(17.67%) nematodes species. The most frequently encountered were nematodes with a prevalence of 66.38% (in 154 samples), followed by the trematodes in 41 samples with a prevalence of 17.67%, cestodes in 28(12.07%) and the least protozoa in 9(3.88%). The parasites encountered are Dicrocoelium dendrititcum 8(3.45%), Taenia saginata 28(12.07%), Ostertagia ostertagi 16(6.89%), Trichuris trichuiria 13(5.60%), Oesophagustomum radiatum 16(6.89%), Bunostomum phlebotomum 22(9.84%), Amphiostomes species 15(6.47%), Haemonchus contortus 16(6.89%), Cooperia pectinata 19(8.19%), Trichostrongylus axei 11(4.74%), Dicrocoelium hospes 5(2.16%), Strongyloides papillosus 11(4.74%), Fasciola hepatica 7(3.02%), Fasciola gigantica 6(2.59%), Oesophagustomum species 12 (5.17%), Dictyocaulus viviparous 7 (3.02%), Ascaris vitulorum 11(4.74%), Eimeria bovis 3(1.29%) and Eimeria zuernii 6 (2.59%). The cestode, T. saginata had the highest prevalence of 12.07% while the protozoa, E. bovis had the lowest 1.29%. Sex and age-related infection were not significantly different at P > 0.05. Likewise, the source, breed and stool consistency related infection were not significantly different.

Prevalensi, Intensitas, dan Dominansi Parasit pada Ikan Manggabai (Glossogobius giuris) di Danau Limboto Provinsi Gorontalo

This study aimed to identify the different types of parasites infecting manggabai fish (Glossogobius giurus) in Lake Limboto, in addition to analyzing the intensity, prevalence, and dominance of parasites in the population. Twenty manggabai fish samples were collected from three different locations in Lake Limboto, namely Dembe 1, Tabmela, and Hutuo. The parasite examination process was carried out at the Zoology Laboratory of the Biology Department of Gorontalo State University, focusing on organs such as skin, gills, fins, and digestive organs. The method applied was the native method, which involves direct observation. The identification results showed the presence of three types of parasites in manggabai fish, namely Gyrodactylus sp., Camallanus sp., and Ligula intestinalis. The highest prevalence was recorded for Gyrodactylus sp. at 65%, indicating a significant spread of parasites in the fish population. The parasite intensity of Camallanus sp. from Hutuo at 7. The parasite Ligula intestinalis showed the highest dominance with a value of 44%. Meanwhile, the highest prevalence and intensity values were placed in the frequent and mild categories.

Detection of Toxoplasma gondii infection in buffaloes (Bubalus bubalis) and cattle (Bos taurus) at the Tabriz abattoir, Iran

AbstractBackgroundToxoplasma gondii is a widely prevalent zoonotic protozoan parasite in humans and warm‐blooded animals worldwide. Infection of humans by this parasite can result in severe clinical symptoms, particularly in individuals with congenital toxoplasmosis or immunocompromised patients. Contamination mainly occurs through foodborne routes, especially the consumption of raw or undercooked meat from animals.ObjectivesThe aim of this study was to use PCR to detect T. gondii in tissues and organs of buffaloes and cattle slaughtered at Tabriz slaughterhouse, in Iran.MethodsFifty grams of heart, thigh, diaphragm and tongue from 50 buffaloes and 100 cattle slaughtered at the Tabriz industrial slaughterhouse were selected for sampling using a combination of convenience sampling. The samples were tested using a previously published PCR method.ResultsOut of the 150 animal samples, T. gondii was detected in 10 (6.7%, 95%CI: 3.2–11.9), including one buffalo (2%, 95%CI: 0.1–10.6) and nine cattle (9%, 95%CI: 4.2–16.4). There was no statistically significant difference in the rate of T. gondii infection among cattle based on age and sex (p > 0.05).ConclusionsThe results indicated a potential risk of T. gondii transmission to humans through the consumption of infected meat. Therefore, appropriate and effective preventive measures should be taken to limit the transmission of this parasite to humans, and the consumption of raw and undercooked meat should be discouraged.

Comparative study of the parasite load in two breeds of sheep in Mexico

Gastrointestinal parasites (GIP) produce great economic losses in livestock systems in Mexico, causing deficiencies in productive systems, mainly in food production; Gastrointestinal parasitosis constitutes a mechanism of loss, due to the high degrees of infestation experienced by these ruminants, which mainly causes anemia, liver and kidney damage, weight loss and large reproductive losses such as very prolonged postpartum anestrus. The prevalence of parasites in sheep is estimated between 63.4% to 90.2% prevalence, in a population of 8.9 million sheep in Mexico, distributed in different zoogeographic zones of the country. Based on the above, the objective of this study was to establish the foundations for the development of a breed or breeds of sheep resistant to gastrointestinal parasites (PGI). To achieve this objective, 183 sheep of the Criolla and Dorper breeds were randomly selected. These were under a grazing system and in addition, phenotypic characteristics were determined such as: body condition, FAMACHA, hematocrit (%). Fecal samples were taken from each animal and analyzed using sedimentation, flotation and direct coproparasitological tests, and the parasite load, eggs per gram of feces (HPG), was determined using the Mac Master chamber method (modified) by animal. To detect the damage caused by the different degrees of parasite infestation, tests were carried out on the metabolomics-metabolic profile of each animal depending on the type of parasite and total parasite load. The data obtained showed that the most prevalent GIP were: Strongyloides papillosus (38.15%), Trichostrongylus spp (32.91%), Haemonchus contortus (21.25%), Trichuris ovis (7.69), Oesophagostomun spp (2 .56%), Ascaris spp (1.56). and Fasciola hepatica (1.32%), this last parasite is not considered a gastrointestinal parasite, according to many authors, however, the laboratory does consider it. The values ​​of metabolites detected through the metabolic profile showed that the higher the parasite load-EGF, these metabolites fluctuated at low levels compared to clinically healthy animals (CHA) such as: glucose, PT, albumin, creatinine, while bilirubin tends to increase, the greater the parasite load-HPG, but this will also depend on the type of parasites that each animal presents; while the alkaline phosphatase enzyme tends to decrease when the EGF is higher. Hematocrit (%) values ​​decreased with respect to high parasite loads, mainly due to Haemochus contortus and Fasciola hepatica. In conclusion: GIP parasites play a significant role in the productive and reproductive development of these breeds of small ruminants, therefore, to produce sheep resistant to GIP it is necessary to detect which parasites are the most prevalent and which ones affect the metabolic activity of each animal or groups of sheep depending on their breed and diet, mainly, and that Creole sheep are more resistant to high GIP loads, they tend to lose weight, but not their reproductive capacity, finally their immune system has to control these loads of GPI, becoming animals with a high degree of resilience in relation to the Dorper breed.

High prevalence and risk of malaria among asymptomatic individuals from villages with high prevalence of artemisinin partial resistance in Kyerwa district of Kagera region, north-western Tanzania

BackgroundAlthough Tanzania adopted and has been implementing effective interventions to control and eventually eliminate malaria, the disease is still a leading public health problem, and the country experiences heterogeneous transmission. Recent studies reported the emergence of parasites with artemisinin partial resistance (ART-R) in Kagera region with high prevalence (> 10.0%) in two districts of Karagwe and Kyerwa. This study assessed the prevalence and predictors/risk of malaria infections among asymptomatic individuals living in a hyperendemic area where ART-R has emerged in Kyerwa District of Kagera region, north-western Tanzania.MethodsThis was a community-based cross-sectional survey which was conducted in July and August 2023 and involved individuals aged ≥ 6 months from five villages in Kyerwa district. Demographic, anthropometric, clinical, parasitological, type of house inhabited and socio-economic status (SES) data were collected using electronic capture tools run on Open Data Kit (ODK) software. Predictors/risks of malaria infections were determined by univariate and multivariate logistic regression, and the results were presented as crude (cORs) and adjusted odds ratios (aORs), with 95% confidence intervals (CIs).ResultsOverall, 4454 individuals were tested using rapid diagnostic tests (RDTs), and 1979 (44.4%) had positive results. The prevalence of malaria infections ranged from 14.4% to 68.5% and varied significantly among the villages (p < 0.001). The prevalence and odds of infections were significantly higher in males (aOR = 1.28, 95% CI 1.08 –1.51, p = 0.003), school children (aged 5–≤10 years (aOR = 3.88, 95% CI 3.07–4.91, p < 0.001) and 10–≤15 years (aOR = 4.06, 95% CI 3.22–5.13, p < 0.001)) and among individuals who were not using bed nets (aOR = 1.22, 95% CI 1.03–1.46, p = 0.024). The odds of malaria infections were also higher in individuals with lower SES (aOR = 1.42, 95% CI 1.17–1.72, p < 0.001), and living in houses without windows (aOR = 2.08, 95% CI 1.46–2.96, p < 0.001), partially open (aOR = 1.33, 95% CI 1.11–1.58, p = 0.002) or fully open windows (aOR = 1.30, 95%CI 1.05–1.61, p = 0.015).ConclusionThe five villages had a high prevalence of malaria infections and heterogeneity at micro-geographic levels. Groups with higher odds of malaria infections included school children, males, and individuals with low SES, living in poorly constructed houses or non-bed net users. These are important baseline data from an area with high prevalence of parasites with ART-R and will be useful in planning interventions for these groups, and in future studies to monitor the trends and potential spread of such parasites, and in designing a response to ART-R.

A Cross-sectional Study of Prevalence of Gastrointestinal Parasites in Captive Wild Animals in Pakistan Zoological Gardens

The animals held captive in zoos often face health and well-being issues. Parasitic infections can lead to health problems in wildlife animals by affecting their gastrointestinal tract. Therefore, the present study aimed to identify and evaluate the population of the various Gastrointestinal (GIT) parasites of wild animals enclosed in different zoological gardens in Pakistan. The fresh fecal samples (n = 960) of 20 captive wildlife animals were collected from Marghzar Zoo, Islamabad (n = 340), Ayub National Park, Rawalpindi (n = 221), Lohi Bher Wildlife Park, Rawalpindi (n = 296), and Bansra Galli Wildlife Park, Rawalpindi (n = 103). The samples were obtained from wildlife mammals, including urial (n = 95), blue bull (n = 106), chinkara gazelle (n = 77), zebra (n = 77), hog deer (n = 75), spotted deer (n = 43), blackbuck (n = 58), barking deer (n = 52), red deer (n = 104), yak (n = 44), grey goral (n = 40), lion (n = 37), mouflon sheep (n = 46), red fox (n = 12), bear (n = 37), grey wolf (n = 12), jackal (n = 12), vervet monkey (n = 12), rhesus monkey (n = 12), and langoor (n = 12). Various methods, such as direct smear examination, standard sedimentation, and floatation techniques were applied to detect and identify the endoparasites in the fecal sample. The detailed routine parasitological analysis identified approximately 52 endoparasites in the fecal samples, including Haemonchus contortus, Eimeria bovis, Ostertagia curcumcincta, Strongyloides papillosus, Strogylus equinus, Oxyuris equi, Chabertia ovina, Protostrongylus, and Trichostrongylus vitrines. The obtained results indicated that Lohi Bher Wildlife Park (46.35%) had a higher prevalence of GIT parasites, compared to Marghzar Zoo (33.23%), Bansra Galli Wildlife Park (33.02%), and Ayub National Park (19.45%). The study reports mild to moderate parasitic infection in captive wild animals and that could affect the survivability of the animals in captivity. The findings of the study can be used to formulate a proper health protocol and sanitation management in captive wild animals to control parasitic infections.

Prevailing parasitic diseases affecting Oreochromis aureus in Lake Burullus.

Lake Burullus is an important source of fish production in Egypt; it produces 20.5% of the Egyptian fisheries' production. There is intense controversy about the heavy metal pollution in Burullus water and its effects on fish health and safety for human consumption. Heavy metals represent a major concern for aquatic life and could negatively affect fish health. Agricultural and industrial water drainage represents a considerable part of the lake water supply. The present work was conducted to determine heavy metal concentrations in lake water and blue tilapia Oreochromis aureus musculature. Water samples were collected from six locations to determine cadmium, copper, lead, zinc and iron. Sixty O. aureus fish samples were also collected from the same sampling points to assess the prevalent parasites infesting fish and to determine the heavy metal (Cd, Cu, Pb, Zn and Fe) concentrations in fish musculature then study the relationship between heavy metals concentration and prevailing fish parasites. Results indicated that 53.34% of the examined fish were infested with encysted metacercaria. Centrocestus formosanus, Prohemistomum vivax, and Euclinostomum heterostomum were retrieved from gills, musculature, hepatopancreas and the posterior kidney. The parasitic intensity in fish tissues was between 1 and 9 cystg-1. Centrocestus formosanus was identified using the polymerase chain reaction in the gill tissues of 16 fish. The gill parasitic copepod Lamproglena monodi was identified in one fish. Degenerative changes such as thickening, corrugation, and destruction of gill filament are the most dominant pathological changes in infested fish gills. Heavy metal concentrations in water samples were at normal levels, except for copper and iron in the southern part of the lake. All heavy metals in fish musculature were below the permissible limits. The parasitic infestation was more dominant in the northern part of the lake than in the southern region; this could be due to elevated copper concentration in the southern part of the lake that could negatively affect the survival of the first intermediate host and parasite cercaria. In conclusion, captured fish from Lake Burullus were safe for human consumption, and heavy metal pollution in lake water does not represent a severe risk.

Parasite prevalence is determined by infection state- and risk-dependent dispersal of the host.

The spread of parasites and the emergence of disease are currently threatening global biodiversity and human welfare. To address this threat, we need to better understand those factors that determine parasite persistence and prevalence. It is known that dispersal is central to the spatial dynamics of host-parasite systems. Yet past studies have typically assumed that dispersal is a species-level constant, despite a growing body of empirical evidence that dispersal varies with ecological context, including the risk of infection and aspects of host state such as infection status (parasite-dependent dispersal; PDD). Here, we develop a metapopulation model to understand how different forms of PDD shape the prevalence of a directly transmitted parasite. We show that increasing host dispersal rate can increase, decrease or cause a non-monotonic change in regional parasite prevalence, depending on the type of PDD and characteristics of the host-parasite system (transmission rate, virulence, and dispersal mortality). This result contrasts with previous studies with parasite-independent dispersal which concluded that prevalence increases with host dispersal rate. We argue that accounting for host dispersal responses to parasites is necessary for a complete understanding of host-parasite dynamics and for predicting how parasite prevalence will respond to changes such as human alteration of landscape connectivity. This article is part of the theme issue 'Diversity-dependence of dispersal: interspecific interactions determine spatial dynamics'.

LLIN Evaluation in Uganda Project (LLINEUP)–effects of a vector control trial on Plasmodium infection prevalence and genotypic markers of insecticide resistance in Anopheles vectors from 48 districts of Uganda

Pyrethroid bednets treated with the synergist piperonyl butoxide (PBO) offer the possibility of improved vector control in mosquito populations with metabolic resistance. In 2017–2019, we conducted a large-scale, cluster-randomised trial (LLINEUP) to evaluate long-lasting insecticidal nets (LLINs) treated with a pyrethroid insecticide plus PBO (PBO LLINs), as compared to conventional, pyrethroid-only LLINs across 104 health sub-districts (HSDs) in Uganda. In LLINEUP, and similar trials in Tanzania, PBO LLINs were found to provide greater protection against malaria than conventional LLINs, reducing parasitaemia and vector density. In the LLINEUP trial, we conducted cross-sectional household entomological surveys at baseline and then every 6 months for two years, which we use here to investigate longitudinal changes in mosquito infection rate and genetic markers of resistance. Overall, 5395 female Anopheles mosquitoes were collected from 5046 households. The proportion of mosquitoes infected (PCR-positive) with Plasmodium falciparum did not change significantly over time, while infection with non-falciparum malaria decreased in An. gambiae s.s., but not An. funestus. The frequency of genetic markers associated with pyrethroid resistance increased significantly over time, but the rate of change was not different between the two LLIN types. The knock-down resistance (kdr) mutation Vgsc-995S declined over time as Vgsc-995F, the alternative resistance mutation at this codon, increased. Vgsc-995F appears to be spreading into Uganda. Distribution of LLINs in Uganda was previously found to be associated with reductions in parasite prevalence and vector density, but here we show that the proportion of infective mosquitoes remained stable across both PBO and non-PBO LLINs, suggesting that the potential for transmission persisted. The increased frequency of markers of pyrethroid resistance indicates that LLIN distribution favoured the evolution of resistance within local vectors and highlights the potential benefits of resistance management strategies.Trial registration: This study is registered with ISRCTN, ISRCTN17516395. Registered 14 February 2017, http://www.isrctn.com/ISRCTN17516395.

Structural characterization of the (deoxy)hypusination in Trichomonas vaginalis questions the bifunctionality of deoxyhypusine synthase.

Trichomonas vaginalis, the causative agent of trichomoniasis, is a prevalent anaerobic protozoan parasite responsible for the most common nonviral sexually transmitted infection globally. While metronidazole and its derivatives are approved drugs for this infection, rising resistance necessitates the exploration of new antiparasitic therapies. Protein posttranslational modifications (PTMs) play crucial roles in cellular processes, and among them, hypusination, involving eukaryotic translation factor 5A (eIF5A), has profound implications. Despite extensive studies in various organisms, the role of hypusination in T. vaginalis and its potential impact on parasite biology and pathogenicity remain poorly understood. This study aims to unravel the structural basis of the hypusination pathway in T. vaginalis using X-ray crystallography and cryo-electron microscopy. The results reveal high structural homology between T. vaginalis and human orthologs, providing insights into the molecular architecture of eIF5A and deoxyhypusine synthase (DHS) and their interaction. Contrary to previous suggestions of bifunctionality, our analyses indicate that the putative hydroxylation site in tvDHS is nonfunctional, and biochemical assays demonstrate exclusive deoxyhypusination capability. These findings challenge the notion of tvDHS functioning as both deoxyhypusine synthase and hydroxylase. The study enhances understanding of the hypusination pathway in T. vaginalis, shedding light on its functional relevance and potential as a drug target, and contributing to the development of novel therapeutic strategies against trichomoniasis.

Hematodinium perezi (Dinophyceae: Syndiniales) in Morocco: The First Record on the African Atlantic Coast and the First Country Record of a Parasite of the Invasive Non-Native Blue Crab Callinectes sapidus

Dinoflagellates belonging to the genus Hematodinium are key parasites of marine crustaceans, primarily decapods. In this study, we document the first report of H. perezi Chatton &amp; Poisson, 1930 on the African Atlantic coast. This is also the first parasite record in the invasive non-native Atlantic blue crab Callinectes sapidus Rathbun, 1896 in Morocco. Specimens of C. sapidus were sampled in winter 2023 from two Ramsar sites on the Moroccan Atlantic, namely Merja Zerga and Oualidia Lagoons, and were screened to detect the presence of parasites in their hemolymph. Based on staining fresh hemolymph smears, we did not detect Hematodinium in any of the 36 investigated individuals (20 and 16 from Merja Zerga and Oualidia Lagoons, respectively), probably due to methodological artifacts. The PCR-based method was revealed to be more accurate in diagnosing the Hematodinium parasite. It showed that at Merja Zerga Lagoon, 13 individuals of C. sapidus were infected by the parasite (prevalence: 65%) in comparison to four at Oualidia Lagoon (25%). Genetic analysis, based on the ITS1 rDNA gene from Hematodinium, confirmed the sequences as being those of Hematodinium perezi.

Patterns in parasite diversity and interactions with anurans from the Atlantic Forest

Knowledge of parasite-host interactions is essential for understanding factors associated with the ecology and evolution of both groups. Some aspects, such as host size and phylogeny, as well as parasite specificity, are significant predictors that help unveil the parasite-host relationship. Thus, the goals of this study were: (1) to describe parasite diversity in regions of the Atlantic Forest; (2) to analyze which host characteristics can influence parasite richness of anuran's parasite component community; and (3) to investigate if the prevalence of parasite infection is related to specificity metrics (ecological and phylogenetic), number of infected hosts and parasite's abundance. We identified 49 parasite taxa, classified into three phyla: Nematoda, Acanthocephala, and Platyhelminthes. Supporting the existing literature, our findings corroborate the positive relationship between host size and parasite richness, further emphasizing the significance of this predictor. Parasite prevalence in the host community is related to the number of infected host species and parasite abundance, but not to phylogenetic and ecological specificity indices. This shows that parasite prevalence is strongly associated with infection opportunity, host sampling effort, and high parasite abundance.

High parasite prevalence in an ecosystem engineer correlated with both local- and landscape-level factors.

Spatial variation in parasitic infection may have many physical and biological drivers. Uncovering these drivers may be especially important for parasites of ecosystem engineers because the engineers are foundational to their communities. Oysters are an important coastal ecosystem engineer that have declined drastically worldwide, in part due to enhanced cases of lethal oyster diseases, such as Dermo and MSX, caused by the protozoan parasites Perkinsus marinus and Haplosporidium nelsoni, respectively. Besides water quality and hydrodynamics, there is little information on how other variables influence the prevalence and intensity of these pathogens in oysters across a regional scale. To examine drivers of spatial variation in these oyster parasites-including host size, local reef properties, and landscape properties-we sampled 24 reefs systematically spread along the coast of Georgia, USA. Across sites, we found universally high prevalence of oysters with at least one of these parasites (91.02% ± 8.89, mean ± SD). Not only are high levels of parasite prevalence potentially problematic for a pivotal ecosystem engineer, but also low spatial variability may limit the explanatory power of variables across a regional scale. Our statistical models explained between 18 and 42% of the variation in spatial patterns of prevalence and intensity of these microparasites. Interestingly, landscape context was a positive predictor of P. marinus, but a negative predictor of H. nelsoni. Overall, our findings suggest that factors driving parasite prevalence and intensity operate across multiple spatial scales, and the same factor can both facilitate and hinder different parasites within the same host species.

Gastrointestinal parasitic infections: Prevalence and risk factors in West Ismailia, Arab Republic of Egypt

BackgroundThis study aimed to determine the prevalence of gastrointestinal parasites (GIP) in the rural community of West Ismailia and its associated risk factors. Human infection by GIP is natural and expected. There are few records concerning parasitic infection in the rural areas of the Ismailia Governorate.MethodsFrom 520 individuals, sociodemographic and risk factors information were retrieved. Fecal samples were collected, concentrated, and tested for GIP infection using a microscopic examination.ResultsThe West Ismailia study population had a 40.4% prevalence of GIP infection, including single and concomitant parasite infections. The most common cause of GIP infection was protists (38%). Entamoeba sp., Blastocystis sp., and G. duodenalis were the most common parasites. Poly-parasitism was prevalent within the West Ismailia region. Age, abdominal symptoms, perianal itching, ownership of numerous animal species, exposure to turbid water, previous parasitic infection (PPI), and non-treatment reception of PPI were all considered significant factors associated with GIP infection. Specific individuals from the same family have been observed to have identical GIP.ConclusionGIP infection remains underestimated in rural areas. Periodic screening and treatment for GIP infection in children and public education on GIP hazards and prevention, focusing on personal hygiene, are recommended. Family members of affected individuals should be screened and treated for GIP.