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Parasites & Vectors Jun 2022The WHO has established a control strategy for Strongyloides stercoralis in school-aged children as well as targets and to maintain control programs for Ascaris...
BACKGROUND
The WHO has established a control strategy for Strongyloides stercoralis in school-aged children as well as targets and to maintain control programs for Ascaris lumbricoides, Trichuris trichiura and hookworms. For an efficient development of control programs, it is necessary to know the target countries around the world, as well as the areas within each country where efforts should be focused. Therefore, maps that provide information on the areas at risk for soil-transmitted helminth (STH) infections on a national and sub-national scale would allow for a better allocation of resources.
METHODS
We used the ecological niche models MaxEnt and Kuenm R library to estimate the global distribution of S. stercoralis and hookworms. We used occurrence points of both species extracted from surveys of two literature reviews and from the Global Atlas of Helminth Infection database, together with 14 raster maps of environmental variables.
RESULTS
We obtained two raster maps with the presence probability of S. stercoralis and hookworm infections at a global level and then estimated the global population at risk to be 2.6 and 3.4 billion, respectively. The population at risk was also estimated at the country level using estimations for areas as small as 25 km. A relationship was found between the probability of the presence of S. stercoralis and its prevalence, and a raster map was generated. Annual precipitation, annual temperature, soil carbon content and land cover were the main associated environmental variables. The ecological niches of Strongyloides stercoralis and hookworms had an overlap of 68%.
CONCLUSIONS
Here we provide information that can be used for developing more efficient and integrated control strategies for S. stercoralis and hookworm infections. This information can be annexed to the study of other risk factors or even other diseases to assess the health status of a community. GRAPHICAL ABSTARCT.
Topics: Ancylostomatoidea; Animals; Ascaris lumbricoides; Child; Ecosystem; Feces; Helminthiasis; Hookworm Infections; Humans; Prevalence; Soil; Strongyloides stercoralis; Strongyloidiasis
PubMed: 35676740
DOI: 10.1186/s13071-022-05284-w -
Biomolecules Apr 2022Diabetes is recognised as the world's fastest growing chronic condition globally. Helminth infections have been shown to be associated with a lower prevalence of type 2...
Diabetes is recognised as the world's fastest growing chronic condition globally. Helminth infections have been shown to be associated with a lower prevalence of type 2 diabetes (T2D), in part due to their ability to induce a type 2 immune response. Therefore, to understand the molecular mechanisms that underlie the development of T2D-induced insulin resistance, we treated mice fed on normal or diabetes-promoting diets with excretory/secretory products (ES) from the gastrointestinal helminth . We demonstrated that treatment with crude ES products from adult worms (AES) or infective third-stage larvae (L3ES) from improved glucose tolerance and attenuated body weight gain in mice fed on a high glycaemic index diet. ES administration to mice was associated with a type 2 immune response measured by increased eosinophils and IL-5 in peripheral tissues but not IL-4, and with a decrease in the level of IL-6 in adipose tissue and corresponding increase in IL-6 levels in the liver. Moreover, treatment with AES or L3ES was associated with significant changes in the community composition of the gut microbiota at the phylum and order levels. These data highlight a role for ES in modulating the immune response associated with T2D, and suggest that ES contain molecules with therapeutic potential for treating metabolic syndrome and T2D.
Topics: Ancylostomatoidea; Animals; Diabetes Mellitus, Type 2; Disease Models, Animal; Glucose; Insulin Resistance; Interleukin-6; Mice; Nippostrongylus
PubMed: 35625566
DOI: 10.3390/biom12050637 -
Science Advances May 2022Endogenous viral elements (EVEs), accounting for 15% of our genome, serve as a genetic reservoir from which new genes can emerge. Nematode EVEs are particularly diverse...
Endogenous viral elements (EVEs), accounting for 15% of our genome, serve as a genetic reservoir from which new genes can emerge. Nematode EVEs are particularly diverse and informative of virus evolution. We identify Atlas virus-an intact retrovirus-like EVE in the human hookworm , with an envelope protein genetically related to G-G glycoproteins from the family Phenuiviridae. A cryo-EM structure of Atlas G reveals a class II viral membrane fusion protein fold not previously seen in retroviruses. Atlas G has the structural hallmarks of an active fusogen. Atlas G trimers insert into membranes with endosomal lipid compositions and low pH. When expressed on the plasma membrane, Atlas G has cell-cell fusion activity. With its preserved biological activities, Atlas G has the potential to acquire a cellular function. Our work reveals structural plasticity in reverse-transcribing RNA viruses.
Topics: Ancylostomatoidea; Animals; Humans; Phlebovirus; RNA Viruses; Viral Envelope Proteins; Viral Fusion Proteins; Virus Internalization
PubMed: 35544562
DOI: 10.1126/sciadv.abj6894 -
The Lancet. Microbe Jan 2022The global distribution and morbidity effects for each specific hookworm species is unknown, which prevents implementation of the optimum intervention for local hookworm... (Review)
Review
The global distribution and morbidity effects for each specific hookworm species is unknown, which prevents implementation of the optimum intervention for local hookworm control. We did two systematic reviews of studies on the proportion of hookworm isolates of each species and genus by region of the world and associations between hookworm species-specific infections and morbidity outcomes, particularly severe anaemia. Necator americanus and Ancylostoma spp were present in all regions of the world, although at different ratios. No clear evidence was found for the differential morbidity effects of different hookworm species. Diagnostic methods that differentiate between hookworm species, including molecular methods, need to be developed for widespread use in control programmes to elucidate key features of hookworm epidemiology and control.
Topics: Ancylostoma; Ancylostomatoidea; Animals; Feces; Hookworm Infections; Humans; Morbidity
PubMed: 35544117
DOI: 10.1016/S2666-5247(21)00181-6 -
Scientific Reports Apr 2022The dual effects of co-infection of Plasmodium spp. and hookworm on malaria remain under debate. This study investigated prevalence, prevalence odds ratio (POR) of... (Meta-Analysis)
Meta-Analysis
The dual effects of co-infection of Plasmodium spp. and hookworm on malaria remain under debate. This study investigated prevalence, prevalence odds ratio (POR) of co-infection and impact of co-infection on malaria parasite density and haemoglobin levels in comparison to Plasmodium mono-infection. The protocol for this systematic review and meta-analysis is registered at PROPERO under ID: CRD42020202156. Relevant literatures were obtained from PubMed, ISI Web of Science, and Scopus on 25 December 2020. Mean difference (MD) and confidence interval (CI) of malaria parasite density and haemoglobin were compared using a random effect model. Heterogeneity was assessed using Cochrane Q and I statistics. Publication bias was determined by visualising funnel plot asymmetry. Of 1756 articles examined, 22,191 malaria cases across 37 studies included 6096 cases of co-infection of Plasmodium spp. and hookworm. The pooled prevalence was 20% (95% CI 15-26%, I 99.6%, 37 studies) and was varied in terms of geographical region. Co-infection occurred by chance (OR 0.97, p 0.97, 95% CI 0.73-1.27, I 95%, 30 studies). The mean malaria parasite density for co-infection (478 cases) was similar to Plasmodium mono-infection (920 cases) (p 0.24, MD 0.86, 95% CI - 0.58-2.29, I 100%, 7 studies). The mean haemoglobin level for co-infection (90 cases) was similar to Plasmodium mono-infection (415 cases) (p 0.15, MD - 0.63, 95% CI - 1.49-0.23, I 98%, 4 studies). Co-infection was common and occurred by chance but varied by geographic region. Further studies are required to investigate the mechanism of hookworm infection on malaria severity. Additionally, detection of hookworm infections among patients with malaria in endemic areas of both diseases is recommended to prevent severe malaria.
Topics: Ancylostomatoidea; Animals; Coinfection; Hookworm Infections; Humans; Malaria; Parasites; Plasmodium; Prevalence
PubMed: 35477943
DOI: 10.1038/s41598-022-10569-2 -
Parasites & Vectors Apr 2022Little is known about the prevalence of Ancylostoma in dogs in the Caribbean. In view of the number of owned free-roaming and feral dogs within the islands and the ideal... (Review)
Review
BACKGROUND
Little is known about the prevalence of Ancylostoma in dogs in the Caribbean. In view of the number of owned free-roaming and feral dogs within the islands and the ideal subtropical climate for parasite development and environmental survival, Ancylostoma could pose a threat to the health of the dogs as well as a zoonotic risk to people.
METHODS
To determine whether generalities about Ancylostoma in dogs in the Caribbean could be made and to obtain a better understanding of the prevalence, published (Scielo, Scopus, and PubMed databases) and gray (e.g., student theses, conference presentations) literature was reviewed. Retrieved manuscripts were screened, and relevant data (year, location, dog population, method of diagnosis, positivity rate) were extracted. Data from two dog populations on St. Kitts also were included: a 2014 field study involving dogs with limited veterinary care and data from the Ross University School of Veterinary Medicine's Veterinary Clinic records for 2018-2019.
RESULTS
Fourteen manuscripts from the 1950s to 2019, representing ten of the Caribbean islands/countries and the Bahamas, were identified. Methods of diagnosing infection status ranged from simple qualitative or quantitative flotation methods to centrifugation with Sheather's sugar flotation solution or necropsy. Dog populations sampled included stray, owned free-roaming, and owned confined. Reported rates of Ancylostoma infection ranged from 10 to 91%. Studies from the last 10 years indicate positivity rates of 21 to 73%. Ancylostoma positivity rates in the St. Kitts' populations were 61% and 10% for the 2014 and 2018-2019 populations, respectively.
CONCLUSIONS
There was no indication that hookworm prevalence has changed over time in the Caribbean, and there were no obvious differences between owned and unowned dogs or free-roaming and confined dogs. The data from St. Kitts were on par with positivity rates from the other islands within the last 10 years and reflective of the impact that veterinary care, including anthelmintic treatment, is expected to have on parasites in pets. There is a clear need to expand the available data for the region and improve control programs for Ancylostoma infections to protect both canine and human health.
Topics: Ancylostoma; Ancylostomatoidea; Animals; Caribbean Region; Dog Diseases; Dogs; Feces; Humans; Parasites; West Indies
PubMed: 35449121
DOI: 10.1186/s13071-022-05254-2 -
BioMed Research International 2022The three main intestinal helminth infections (IHIs), ascariasis, trichuriasis, and hookworm, are common clinical disorders worldwide. These IHIs are more prevalent in...
The three main intestinal helminth infections (IHIs), ascariasis, trichuriasis, and hookworm, are common clinical disorders worldwide. These IHIs are more prevalent in tropics and subtropical countries especially in developing countries like sub-Saharan Africa responsible for morbidity, mortality, and physical as well as intellectual growth retardation in children. In Ethiopia, the burden of IHIs appears in all ages mainly due to factors like lack of education, low socio-economic status, and inadequate supply of drugs and proper awareness. The present study was carried out to access the prevalence of intestinal helminth infections and associated risk factors among school children in Adola town from Guji Zone, Oromia, Ethiopia, from August 2019 to December 2019. 404 stool samples were collected in a clean, dry, screw-capped, and wide-mouthed plastic container, fixed with 10% formal-saline solution, and transported to the Adola Hospital laboratory for further microscopic analysis by wet mount following formal ether concentration technique. Data were analyzed using SPSS version 20 by binary logistic regression model using odd ratio with 95% CI. The overall prevalence of IHIs among school children was found to be 33.91% (137/404). Rate of double infection was noted to be 2.72% (11/404). Most dominant species was (8.9%) followed by (7.7%), (5.4%), hookworm (4.7%), (2.5%), (2.2%), (1.7%), and (0.7%), respectively. Highest prevalence was observed in male students (39.6%) compared to female students (28.8%) ( < 0.05). The prevalence of IHIs among school children in the age group of 6-10, 11-15, 16-20, and above 20 was 49.6%, 35.8%, 10.9%, and 3.6%, respectively ( < 0.05). IHI was significantly associated with some of the risk factors such as gender, educational level of students', toilet usage habit, habit of hand washing, hand washing habit before feeding and after defecation, purpose of hand washing, and awareness to intestinal helminths ( < 0.05). In the study area, the prevalence of IHIs is moderately high and represents a public health problem in the school children. Therefore, all stakeholders should pay attention to raise awareness about health education programs such as proper personal hygiene, environmental sanitation, improving the quality of drinking water, and treatment to reduce the consequences of intestinal helminths.
Topics: Ancylostomatoidea; Animals; Ascaris lumbricoides; Child; Cross-Sectional Studies; Ethiopia; Feces; Female; Helminthiasis; Humans; Intestinal Diseases, Parasitic; Male; Prevalence; Risk Factors
PubMed: 35445136
DOI: 10.1155/2022/5908938 -
BMC Veterinary Research Apr 2022Bacterial infections are responsible of high economic losses in aquaculture. Mexican golden trout (Oncorhynchus chrysogaster) is a threatened native trout species that...
Bacterial and parasite co-infection in Mexican golden trout (Oncorhynchus chrysogaster) by Aeromonas bestiarum, Aeromonas sobria, Plesiomonas shigelloides and Ichthyobodo necator.
BACKGROUND
Bacterial infections are responsible of high economic losses in aquaculture. Mexican golden trout (Oncorhynchus chrysogaster) is a threatened native trout species that has been introduced in aquaculture both for species conservation and breeding for production and for which no studies of bacterial infections have been reported.
CASE PRESENTATION
Fish from juvenile stages of Mexican golden trout showed an infectious outbreak in a farm in co-culture with rainbow trout (Oncorhynchus mykiss), showing external puntiform red lesions around the mouth and caudal pedunculus resembling furuncles by Aeromonas spp. and causing an accumulated mortality of 91%. Isolation and molecular identification of bacteria from lesions and internal organs showed the presence of Aeromonas bestiarum, Aeromonas sobria, Plesiomonas shigelloides and Ichthyobodo necator isolated from a single individual. All bacterial isolates were resistant to amoxicillin-clavulanic acid and cefazoline. P. shigelloides was resistant to third generation β-lactamics.
CONCLUSIONS
This is the first report of coinfection by Aeromonas bestiarum, Aeromonas sobria, Plesiomonas shigelloides and Ichthyobodo necator in an individual of Mexican golden trout in co-culture with rainbow trout. Resistance to β-lactams suggests the acquisition of genetic determinants from water contamination by human- or livestock-associated activities.
Topics: Aeromonas; Animals; Coinfection; Fish Diseases; Gram-Negative Bacterial Infections; Necator; Oncorhynchus; Oncorhynchus mykiss; Parasites; Plesiomonas
PubMed: 35414073
DOI: 10.1186/s12917-022-03208-5 -
BMC Infectious Diseases Apr 2022Soil-transmitted helminth (STH) infections are still a major health problem, especially in resource-limited countries. The community-based prevalence of STH is unknown...
BACKGROUND
Soil-transmitted helminth (STH) infections are still a major health problem, especially in resource-limited countries. The community-based prevalence of STH is unknown in Afghanistan. Main objectives of this study were to estimate the prevalence and associated factors of STH among children in Daman district of Kandahar province in Afghanistan.
METHODS
This was a community-based cross-sectional study, with data collected during five months (June-October, 2020) from children living in five villages of Daman district in Kandahar, Afghanistan. All the stool samples were examined by saline wet mount method. Data were analyzed by using descriptive statistics, Chi square test, and multivariate logistic regression.
RESULTS
A total of 1426 children were studied, with majority (61.8%) of males and the mean age of 6.3 years. The overall prevalence of any intestinal parasitic infection was 39.8%. The overall prevalence of STH infection was 22.7%, with Ascaris lumbricoides (18.7%) as the most prevalent STH species, followed by hookworm (7.5%) and Trichuris trichiura (1.4%). Single, double, and triple STH infections were present in 14.9%, 7.2%, and 0.6% of the children, respectively. Multivariate logistic regression revealed that not washing hands after defecating/before eating (AOR 7.0, 95% CI 3.4-14.0), living in mud house (AOR 3.5, 95% CI 1.6-7.4), walking barefoot (AOR 2.2, 95% CI 1.6-3.1), living in overcrowded house (AOR 1.6, 95% CI 1.1-2.3), and practicing open defecation (AOR 1.4, 95% CI 1.1-2.0) as the risk factors associated with the predisposition of rural children for getting STH in Daman district of Afghanistan.
CONCLUSIONS
Prevalence of STH is high among children of Daman district in Afghanistan. Most of the risk factors are related to poverty, decreased sanitation, and improper hygiene. Improvement of socioeconomic status, sanitation, and health education to promote public awareness about health and hygiene together with periodic mass deworming programs are better strategies for the control of STH infections in Afghanistan. Also, government and international donor agencies in Afghanistan should help in improving socio-economic status of the rural areas through provision of basic facilities such as piped water, electricity, good housing, and proper toilets.
Topics: Afghanistan; Ancylostomatoidea; Animals; Child; Cross-Sectional Studies; Feces; Helminthiasis; Humans; Male; Prevalence; Risk Factors; Soil
PubMed: 35410154
DOI: 10.1186/s12879-022-07336-z -
PloS One 2022Soil-transmitted helminths (STH) are one of the most common infections affecting underprivileged populations in low- and middle-income countries. Ascaris lumbricoides,...
BACKGROUND
Soil-transmitted helminths (STH) are one of the most common infections affecting underprivileged populations in low- and middle-income countries. Ascaris lumbricoides, Trichuris trichiura, and hookworm are the three main species that infect people. School children are the most vulnerable groups for STH infections due to their practice of walking and playing barefoot, poor personal hygiene, and environmental sanitation. However, evidence is limited in the study area. So, this study aimed to assess the current prevalence, infection intensity, and associated risk factors of STHs among school children in Tachgayint woreda, Northcentral Ethiopia.
METHODS
A cross-sectional study was conducted among school children of Tachgayint woreda from February to May 2021. The study participants were chosen via systematic random sampling. Stool samples were collected from 325 children and examined using the Kato-Katz technique. The data was analyzed using SPSS version 23. Binary and multivariable logistic regression analyses were used to identify the potential associated factors for STHs. An adjusted odds ratio (AOR) with a 95% confidence interval (CI) was used to measure the magnitude of the association. A P-value <0.05 was considered statistically significant.
RESULTS
The overall prevalence of STHs in this study was 36.0% (95% CI: 30.5-41.2%). Ascaris lumbricoides are the most prevalent species 89 (27.4%) followed by hookworm 14 (4.3%) and Trichuris trichiura 10 (3.1%). All of the infected school children had light-intensity of infections with the mean of eggs per gram (EPG) being 464.53. Lack of shoe wearing habit (AOR = 4.08, 95% CI: 1.29-12.88) and having untrimmed fingernail (AOR = 1.85, 95% CI: 1.06-3.22) were identified as risk factors for STH infections.
CONCLUSIONS
More than one-third of the school children were infected with at least one STH species and this indicates that STHs are still a health problem among school children in the study area. Therefore, periodic deworming, implementation of different prevention strategies, and health education programs should be regularly applied in the area.
Topics: Ancylostomatoidea; Animals; Ascaris lumbricoides; Child; Cross-Sectional Studies; Ethiopia; Feces; Helminthiasis; Helminths; Hookworm Infections; Humans; Prevalence; Risk Factors; Soil; Trichuris
PubMed: 35395035
DOI: 10.1371/journal.pone.0266333