Transmission Of Parasitic Diseases Research Articles

Investigating the relationship between extreme weather and cryptosporidiosis and giardiasis in Colorado: A multi-decade study using distributed-lag nonlinear models

Environmentally-mediated protozoan diseases like cryptosporidiosis and giardiasis are likely to be highly impacted by extreme weather, as climate-related conditions like temperature and precipitation have been linked to their survival, distribution, and overall transmission success. Our aim was to investigate the relationship between extreme temperature and precipitation and cryptosporidiosis and giardiasis infection using monthly weather data and case reports from Colorado counties over a twenty-one year period. Data on reportable diseases and weather among Colorado counties were collected using the Colorado Electronic Disease Reporting System (CEDRS) and the Daily Surface Weather and Climatological Summaries (Daymet) Version 3 dataset, respectively. We used a conditional Poisson distributed-lag nonlinear modeling approach to estimate the lagged association (between 0 and 12-months) between relative temperature and precipitation extremes and the risk of cryptosporidiosis and giardiasis infection in Colorado counties between 1997 and 2017, relative to the risk found at average values of temperature and precipitation for a given county and month. We found distinctly different patterns in the associations between temperature extremes and cryptosporidiosis, versus temperature extremes and giardiasis. When maximum or minimum temperatures were high (90th percentile) or very high (95th percentile), we found a significant increase in cryptosporidiosis risk, but a significant decrease in giardiasis risk, relative to risk at the county and calendar-month mean. Conversely, we found very similar relationships between precipitation extremes and both cryptosporidiosis and giardiasis, which highlighted the prominent role of long-term (>8 months) lags. Our study presents novel insights on the influence that extreme temperature and precipitation can have on parasitic disease transmission in real-world settings. Additionally, we present preliminary evidence that the standard lag periods that are typically used in epidemiological studies to assess the impacts of extreme weather on cryptosporidiosis and giardiasis may not be capturing the entire relevant period.

Ticks analysis for molecular detection and phylogenetic evaluation of stray dogs infecting protozoa from Alborz, Iran

Ticks play an important role in the transmission of parasitic diseases, especially pathogenic protozoa in canine hosts, and it is very important to determine the role and extent of their infection with these pathogens in order to determine important control strategies. This study assessed the molecular prevalence of three protozoan pathogens including Hepatozoon canis, Leishmania spp. and Babesia spp., in ticks using PCR. A total 300 stray dogs were investigated and 691 ticks (171 male, 377 female and 143 nymph) were detected directly from 45 infested dogs. Species, stage of growth, and gender were determined for each tick. DNA extracted from 224 ticks (26 male, 165 female and 33 nymph). The molecular presence of three protozoan pathogens including Hepatozoon spp. (18S rRNA gene), Leishmania infantum (kinetoplastid minicircle DNA) and Babesia spp. (ssrRNA gene) were investigated using PCR method. One species of ticks, Rhipicephalus sanguineus was identified. Two of the target pathogens, Hepatozoon spp. (7/83; 8.43 %) and Babesia spp. (1/83; 1.2 %), were detected by PCR method. Sequence analysis of the ssrRNA gene of detected Babesia spp. showed a close relationship to the deposited strains of Babesia vulpis in the gene bank. To the best of our knowledge, this is the first study to undertake a phylogenetic analysis of H. canis and Babesia spp. in stray dogs in Alborz province, Iran and the first report about molecular detection of Babesia vulpis from tick infesting dogs in Iran. According to the above results, it seems necessary to implement tick control programs in dogs.

Environmental Factors Affecting Freshwater Snail Intermediate Hosts in Shenzhen and Adjacent Region, South China.

Sound knowledge of the local distribution and diversity of freshwater snail intermediate hosts and the factors driving the occurrence and abundance of them is crucial to understanding snail-borne parasitic disease transmission and to setting up effective interventions in endemic areas. In this study, we investigated the freshwater snails, water quality parameters, physical characteristics of habitats, predators and competitors, and human activity variables at 102 sites during December 2018 and August 2019 in Shenzhen and adjacent areas in China. We used decision tree models and canonical correspondence analysis to identify the main environmental and biotic factors affecting the occurrence and abundance of snail species. A total of nine species of snail were collected throughout the study area, with Biomphalaria straminea, Sinotaia quadrata, and Physella acuta being the most predominant species. Our study showed that the most important variables affecting the abundance and occurrence of snail species were the presence of predators and competitors, macrophyte cover, chlorophyll-a, substrate type, river depth, and water velocity. In terms of human activities, snail species occurred more frequently and in larger numbers in water bodies affected by human disturbances, especially for sewage discharge, which may reduce the occurrence and abundance of snail predators and competitors. These findings suggest that proper management of water bodies to reduce water pollution may increase the abundance of snail predators and competitors, and should be considered in integrated snail control strategies in the study area.

Analysis of supplemental wildlife feeding in Mississippi and environmental gastrointestinal parasite load.

Wildlife species are host to a variety of gastrointestinal parasites (GIPs). Artificially concentrating animals may increase the risk of disease spread due to increased GIP load and associated environmental load. Supplemental feeding of deer is common among hunters and known to concentrate animals, but there is limited knowledge of how it affects GIP environmental load. GIP load was compared between ecologically-equivalent pairs of sites in Mississippi with and without year-round supplemental feeding (average distance between pairs = 147 m). During May-August in 2019 and 2020, feces from white-tailed deer and raccoons were collected and examined for the presence of nematodes, coccidia, Giardia spp., Cryptosporidium spp., and Baylisascaris procyonis. On average, fed sites had 8 more deer (241% increase) and 2 more raccoon fecal piles (540% increase) than unfed sites. Average parasite loads for individual fecal samples did not differ between fed and unfed sites, but the greater number of deer and raccoon fecal piles at fed sites (p < 0.0001) produced 231% and 308% greater environmental loads of nematodes and coccidia, respectively. Spin feeders, the only feeder type that distributed feed on the ground, had 326% more coccidia in feces on average compared to other feeder types (p < 0.03). These results show that supplemental feeding of white-tailed deer, especially with spin feeders, increases environmental loads of GIP and the potential for transmission of parasitic diseases.

Potential transmission risk of key parasitic diseases and responses to the risk during the construction of an ecological city in Shanghai Municipality

A blueprint on Shanghai's ecological space design between 2021 and 2035 was released in 2021, aiming to build an ecological city and improve the development of ecological civilization. The transmission of parasitic diseases is strongly associated with climate and ecological environments. Currently, the prevalence of parasitic diseases has been maintained at extremely low-transmission levels, and there are almost no local cases; however, the alteration of ecological environments may results in a potential transmission risk of parasitic diseases. Hereby, the current status of key parasitic diseases in Shanghai Municipality was described, and the potential transmission risk of parasitic diseases and responses to this risk were analyzed during the construction of an ecological city in Shanghai Municipality. In addition, the suggestions pertaining to surveillance and management of parasitic diseases were proposed during the mid- and long-term construction of an ecological city in Shanghai Municipality.

Sağlık Hizmetleri Meslek Yüksekokulu Öğrencilerinin Paraziter Hastalıklar Hakkındaki Bilgi Düzeyleri

In this study, it has been aimed to determine the knowledge level of the students of Van Yuzuncu Yıl University Health Services Vocational School, who will serve as the health personnel of the future, about parasitic diseases, prevention and control measures from these diseases. A total of 587 students, comprising 418 (71.2%) females and 169 (28.8%) males, studying at Van Yüzüncü Yıl University Health Services Vocational School, were included in the study. The questions in the questionnaire were arranged in three groups, as those about parasitic diseases, transmission routes of these diseases, and prevention and treatment. Cronbach alpha coefficients were calculated within the scope of the reliability analysis of the questionnaire questions. The Cronbach alpha values for the domains of Knowledge Level About Parasitic Diseases, Knowledge Level About the Transmission of Parasitic Diseases, and Knowledge Level About the Prevention and Treatment of Parasitic Diseases were determined as 0.647 (64.7%), 0.707 (70.7%), and 0.566 (56.6%), respectively. A statistically significant difference was found between the departments included in the study in terms of the level of knowledge about parasitic diseases (P &amp;lt; 0.05). A statistically significant difference was found between the departments in the evaluation made between the level of knowledge about the prevention and treatment of parasitic diseases and the personal characteristics of the students (P &amp;lt; 0.05). As the result, it was observed that the students participating in the study did not have sufficient knowledge about parasitic diseases.

Risk factors associated with intestinal pathogenic parasites in schoolchildren

Diseases caused by intestinal parasites impose a substantial burden on population of middle income countries including Pakistan. This research was aimed to assess the risk factors for intestinal parasites in school children of Malakand, Pakistan. Two hundred and eighty eight students were enrolled between February and June 2016. Out of the total enrolled 184 were agreed to collect stool specimens. A questionnaire was also used to collect the data on socio-demographic and socio-economic characteristics of the participants. All the students were guided to collect at least 10gof their own stool specimens. Each of the stool specimens was diagnosed for the presence of any stage of helminth or protozoal parasites. Formal ether concentration method and wet mount techniques were applied. One way ANOVA was used for calculation of P value when it was less than 0.05 which was considered significant. Eighty two percent of the participants were found infected with one species of parasite while 69.9% of the participants were infected with more than one species of intestinal parasites. The most prevalent parasite was hook worm 33.4% (n = 99/296) followed by Taenia saginata 28.7% (n = 85/296), Ascaris lumbricoides 27.7% (n = 82/296), Hymenolepis nana 6.08% (n = 18/296), Entamoeba histolytica 3.37% (n = 10/296) and least for each Enterobius vermicularis and Fasciola hepatica 0.37% (n = 1/296). Previously used drugs, level in school, ages, weight and upper arm circumference were the most significantly (P < 0.05) related factors for the occurrence of intestinal parasite infection. Present research endorsed that risk factors play a key role in the transmission of parasitic diseases. Lack of safe water supply, using raw vegetables, animal keeping, which should be considered for sustainable strategies in the control of these infections preferably in remote parts of the world.

The Presence of Fungal and Parasitic Infections in Substances of Human Origin and Their Transmission via Transfusions and Transplantations: Protocol for Two Systematic Reviews.

BackgroundThe European Union Directives stipulate mandatory tests for the presence of any infections in donors and donations of substances of human origin (SoHO). In some circumstances, other pathogens, including fungi and parasites, may also pose a threat to the microbial safety of SoHO.ObjectiveThe aim of the two systematic reviews is to identify, collect, and evaluate scientific evidence for the presence of fungal and parasitic infections in donors and donations of SoHO, and their transmission via transfusion and transplantation.MethodsAn algorithmic search, one each for fungal and parasitic disease, was applied to 6 scientific databases (PubMed, EMBASE, Web of Science, Scopus, Cochrane Library [trials], and CINAHL). Additionally, manual and algorithmic searches were employed in 15 gray literature databases and 22 scientific organization websites. The criteria for eligibility included peer-reviewed publications and peer-reviewed abstract publications from conference proceedings examining the prevalence, incidence, odds ratios, risk ratios, and risk differences for the presence of fungi and parasites in donors and SoHO donations, and their transmission to recipients. Only studies that scrutinized the donors and donations of human blood, blood components, tissues, cells, and organs were considered eligible. Data extraction from eligible publications will be performed independently by two reviewers. Data synthesis will include a qualitative description of the studies lacking evidence suitable for a meta-analysis and a random or fixed-effect meta-analysis model for quantitative data synthesis.ResultsThis is an ongoing study. The systematic reviews are funded by the European Centre for Disease Prevention and Control, and the results are expected to be presented by the end of 2021.ConclusionsThe systematic reviews will provide the basis for developing a risk assessment for fungal and parasitic disease transmission via SoHO.Trial RegistrationPROSPERO International Prospective Register of Systematic Reviews CRD42020160090; https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42020160090 ; PROSPERO International Prospective Register of Systematic Reviews CRD42020160110; https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42020160110International Registered Report Identifier (IRRID)DERR1-10.2196/25674

Who let the dogs out? Exploring the spatial ecology of free-roaming domestic dogs in western Kenya.

The spatial ecology of free‐roaming dogs determines their role in the transmission of zoonoses. This study describes the geographic range of and identifies sites frequently visited by free‐roaming domestic dogs in western Kenya.Eight sites in Busia county, western Kenya, were selected. At each site, ten dog‐keeping households were recruited, a questionnaire was administered, and a GPS logger was fixed around the neck of one dog in each household. Loggers were programmed to capture the dog's position every minute, for five consecutive days. Individual summaries of GPS recordings were produced, and the daily distance traveled was calculated. 50% and 95% utilization distribution isopleths were produced, and the area within these isopleths was extracted to estimate the size of the core and extended Home Ranges (HRs), respectively. Linear regression analyses were performed to identify factors associated with the movement parameters. The centroid points of the 10, 50, and 90% isopleths were reproduced, and the corresponding sites identified on the ground.Seventy‐three dogs were included in the final analyses. The median daily distance traveled was 13.5km, while the median core and extended HRs were 0.4 and 9.3 ha, respectively. Older dogs had a larger extended HR and traveled more daily, while the effect of sex on dog movement depended on their neutering status. Dogs spent most of their time at their household; other frequently visited sites included other household compounds, fields, and rubbish dumps. One of the centroids corresponded to a field located across the international Kenya–Uganda border, emphasizing the fluidity across the border in this ecosystem. Multiple dogs visited the same location, highlighting the heterogeneous contact networks between dogs, and between dogs and people.The field data presented are of value both in understanding domestic dog ecology and resource utilization, and in contextualizing infectious and parasitic disease transmission models.

Parasitological Assessment of Lettuce Quality in the Maxixe City Markets, Mozambique

Introduction: The consumption of lettuce provides several benefits, such as high source of dietary fiber, minerals and vitamins. However, despite these benefits, it can be a vehicle for the transmission of parasitic diseases, taking into account that its consumption is done in a raw way. Thus, this study aimed to assess the parasitological quality of lettuce that is sold in the markets of Maxixe city in Inhambane Province, the southern of Mozambique. Materials and Methods: In June and July 2018, 50 samples of lettuce were purchased in three markets from Maxixe city. The samples were placed in plastic bags, correctly identified and transported to the Laboratory of Microbiology and Parasitology at the Faculty of Health Sciences of Pedagogical University of Mozambique, where the parasites' eggs and larvae were investigated, using the method of Hoffmann and Pons-Janer. The statistical analysis of data was performed by using SPSS program, version 24. Results and Discussion: From 50 samples of lettuce analyzed, 35 of them were positive that corresponds to 70% of the contaminated samples, with the remaining 15 (30%) being negative, with significant differences (X2, P=0.002). The highest contamination rate was found in the Tsuhula market, with 100% of the contaminated samples, followed by Dumbanengue market with 64.7% and finally the Xicadjuanine market with 43.75% of contaminated samples. The parasites found in the lettuce samples were Ascaris lumbricoides, Entamoeba histolytica cysts, Strongyloid stereoralis larvae and Hepatic Fasciola Conclusion: Expressive contamination rates of lettuce sold in the three markets were obtained, with the need to adopt proper hygiene practices before its consumption, in addition to the need to strengthen the health surveillance system.

Adherence to veterinary recommendations for ectoparasiticides purchased by cat owners in the USA

BackgroundSafe and effective flea and tick treatment options for cats are important in companion animal practice because of feline ectoparasite infestation prevalence and the potential for parasitic disease transmission. Retrospective cat owner purchasing transactions at United States of America (USA) veterinary clinics were obtained for three topical feline flea and tick ectoparasiticides. One medication, fluralaner, had a 12-week redosing interval, while two other medications (fipronil/s-methoprene/pyriproxyfen; imidacloprid/pyriproxyfen) were approved for monthly redosing. The annual number of doses purchased by cat owners was determined for each of the three medications and then compared between medications. The objective was to evaluate whether 12-week retreatment intervals resulted in a different duration of coverage compared to monthly treatments for ectoparasiticide products.MethodsStudy results were obtained by analyzing the transactional records from a commercial database derived from veterinary practice management software. The study database consisted of cat owner purchasing records from January 2017 through June 2019 from 671 veterinary practices representing 41,630 cats.ResultsCat owners purchased an average of 1.5 doses of fluralaner per year which, based on a 12-week redosing interval, provides 4.2 months of treatment coverage. Cat owners who used monthly flea and tick medications respectively purchased 3.6 months (fipronil/s-methoprene/pyriproxyfen combination) and 2.8 months (imidacloprid/pyriproxyfen) annually of each of the two medications. Average yearly cat owner purchases of fluralaner provide a significantly longer duration of coverage than for cat owners purchasing fipronil/s-methoprene/pyriproxyfen (17% more) or imidacloprid/pyriproxyfen (50% more).ConclusionsCat owners who obtained a flea and tick treatment with a 12-week redosing interval (fluralaner) protected their cats for up to 17% or 50% longer duration each year, respectively, compared to the duration of protection obtained by cat owners who used a medication re-dosed monthly. Cat owners should increase their duration of flea and tick coverage to come closer to achieving veterinary recommendations.

Intestinal parasitic infections among hemodialysis Sudanese patients.

Background: Intestinal parasitic infections (IPIs) can result in high morbidity and mortality, particularly in immunocompromised patients. Intestinal parasitic infections rate among hemodialysis Sudanese patients studied infrequently. Our paper aimed to examine and determine the prevalence of intestinal parasites among hemodialysis Sudanese patients. Methods: Stool samples were collected from Sudanese patients at a hemodialysis center in Kosti city, White Nile state, Sudan. All stool samples were examined to detect the type of parasites and determine the prevalence using the formol-ether concentration technique and Modified Zeihl Neelsen (ZN) stain technique. Results: The overall prevalence of Intestinal parasitic infections among hemodialysis using the formol-ether concentration technique and Modified Zeihl Neelsen (ZN) stain technique was (28.6%) and (44.6%) respectively. The total prevalence of parasites detected by formol-ether concentration technique; Giardia lamblia (46.9%), Entamoeba histolytica (12.5%), Entamoeba coli (40.6%), and by modified ZN staining technique; Cryptosporidium species (28%) and Isospora belli (8%). The prevalence of IPIs was higher among males than females (74 vs. 26%, respectively; P>0.05) Conclusions: Studying the prevalence of IPIs among hemodialysis Sudanese patients, may predict their health status and lead to better diagnosis and treatment. Health education and personal hygiene were recommended to reduce the transmission of parasitic diseases. This is a first descriptive study of IPIs among hemodialysis in the area of study.

Parasitic Infection Surveillance in Mississippi Delta Children.

.Some recent studies suggest ongoing transmission of parasitic diseases in the American South; however, surveys in Mississippi children are lacking. We enrolled 166 children (median age 8 years, range 4–13 years) from the Mississippi Delta region and carried out multi-parallel real-time polymerase chain reaction (PCR) for Necator americanus, Ascaris lumbricoides, and Strongyloides stercoralis on their stool samples. Dried blood spots were obtained for multiplex serology antibody detection. Of 166 children, all reported having flushable toilets, 11% had soil exposure, and 34% had a pet dog or cat. None had prior diagnosis or treatment of parasitic disease. Multi-parallel real-time PCRs were negative on the 89 stool DNA extracts available for testing. Dried blood spot testing of all 166 children determined the seroprevalence of IgG antibodies to Toxocara spp. (3.6%), Cryptosporidium (2.4%), S. stercoralis, Fasciola hepatica, and Giardia duodenalis (all 0%). In conclusion, parasitic infections and exposure were scarce in this population. Larger studies of at-risk populations are needed.

The Prevalence of Endoparasites of Free Ranging Cats (Felis catus) from Urban Habitats in Southern Poland.

Simple SummaryFree ranging domestic cats are common in urban and suburban habitats and may cause a threat of disease transmission to other pets, wildlife and humans. We investigated the occurrence of endoparasites in cats in Kraków city, Southern Poland, based on examination of road-killed individuals. More than half of the cats were infected with at least one of seven identified parasites. Cats from suburban areas were more likely to be infected than cats from the city core. Our study supports the results from other studies, showing that cats may serve as a significant source of zoonotic transmission.Growing urbanization leads to an increased risk of parasite spread in densely inhabited areas. Free-ranging cats can be locally numerous and come into frequent contact with both wildlife and humans. Cats are thus expected to contribute to parasitic disease transmission. In our study, we investigated the prevalence of endoparasites in free ranging cats in urban areas of Kraków city, based on necropsy of road-killed cats in relation to sex and diet of cat, season and habitat type. We found that 62% of 81 cats were infected with endoparasites with Toxocara cati being the most prevalent. In total, we identified seven parasite species. The number of parasite species was higher in suburban habitats and aside from Eucoleus aerophilus the prevalence of all parasites was higher in cats from suburban areas than in the individuals living in the city urban core. The prey of examined cats included mostly rodents, followed by soricomorphs and birds, which can all serve as paratenic hosts. Based on our results, we suggest that cats in urban areas should be considered as a serious potential zoonotic threat. Implementation of proper veterinary control and wider education on the topic is recommended.

A parasitological evaluation of edible insects and their role in the transmission of parasitic diseases to humans and animals.

From 1 January 2018 came into force Regulation (EU) 2015/2238 of the European Parliament and of the Council of 25 November 2015, introducing the concept of “novel foods”, including insects and their parts. One of the most commonly used species of insects are: mealworms (Tenebrio molitor), house crickets (Acheta domesticus), cockroaches (Blattodea) and migratory locusts (Locusta migrans). In this context, the unfathomable issue is the role of edible insects in transmitting parasitic diseases that can cause significant losses in their breeding and may pose a threat to humans and animals. The aim of this study was to identify and evaluate the developmental forms of parasites colonizing edible insects in household farms and pet stores in Central Europe and to determine the potential risk of parasitic infections for humans and animals. The experimental material comprised samples of live insects (imagines) from 300 household farms and pet stores, including 75 mealworm farms, 75 house cricket farms, 75 Madagascar hissing cockroach farms and 75 migrating locust farms. Parasites were detected in 244 (81.33%) out of 300 (100%) examined insect farms. In 206 (68.67%) of the cases, the identified parasites were pathogenic for insects only; in 106 (35.33%) cases, parasites were potentially parasitic for animals; and in 91 (30.33%) cases, parasites were potentially pathogenic for humans. Edible insects are an underestimated reservoir of human and animal parasites. Our research indicates the important role of these insects in the epidemiology of parasites pathogenic to vertebrates. Conducted parasitological examination suggests that edible insects may be the most important parasite vector for domestic insectivorous animals. According to our studies the future research should focus on the need for constant monitoring of studied insect farms for pathogens, thus increasing food and feed safety.

Analysis of knowledge and attitudes related to parasitic infections among inhabitants of Ahvaz County, Khuzestan Province, Iran

Parasitic diseases are among the major health problems of various societies, especially people in developing countries, causing high economic and mortality burdens. Many researchers have reported that awareness and knowledge of a disease are effective in preventing and controlling the disease. The aim of the present study was to assess the knowledge and attitudes on parasitic diseases of the population in Ahvaz County, southwestern Iran. This community-based cross-sectional study was carried out in 2017 on 3500 subjects above 15 years old of Ahvaz County. First, participants were provided the necessary information regarding the study, and then data were collected using a constructed questionnaire. Of the 3500 participants, 1732 (49.5%) were female and 1768 (50.5%) were male, 348 (9.9%) said that they had been infected with a parasitic disease at least once in their lifetime. Almost half of the participants (42.8%) knew malaria was a parasitic disease and 50.2%, 48.9%, and 41.5% were aware of the possible transmission of parasitic diseases through uncooked meat, dirty hands, and close contact with animals.Regarding clinical symptoms, 73.2% and 32.6% of the respondents knew diarrhea and abdominal pain respectively were clinical symptoms of intestinal parasitic diseases. However, only 31.3% were aware of the close contact with cats and the risk of human toxoplasmosis and possible abortion in pregnant women. The findings reveal that the attitude of most participants toward treatment was positive (93.9%), but only 47.5% of believed that disinfecting fruits and vegetables could prevent intestinal parasitic infections.

Ефективність способів дослідження проб ґрунту на наявність збудників кокцидіозів

One of the factors of transmission of parasitic diseases, including coccidioses of animals is objects of the environment contaminated by invasive elements. It is well known that the greatest intensity of coccidia oocysts contamination is characteristic of the soil - of the place where the exogenous stage of the pathogen development - invasive sporulated oocysts occurs. In this regard, an important issue for scientists and practitioners is the question of studying the actual soil contamination by invasive elements, since it allows predicting the epizootic well-being of herd animals and developing appropriate therapeutic and preventive measures. Thus, the aim of the work was to establish the effectiveness of soil examination methods for the presence of oocysts of eimeries. The paper presents data concerning comparative effectiveness of well-known methods - Romanenko (1968) and Hudzhabidze (1969), Dolbin et al. (2012), as well as an improved method for examining the soil for the presence of coccidia oocysts. The improvement of the new method was carried out by making changes in the indicators: the mass of the studied soil, the time of sedimentation with alkali, centrifugation modes. Also, the composition of the flotation liquid was modified, in which two-component solution (a flotation solution based on inorganic salt in combination with alkali) was used. Romanenko (1968) and Hudzhabidze (1969) used a prototype method. It has been established that the proposed method turned out to be the most effective in relation to the indicators of the number of positive samples, the total number of detected oocysts and their conversion to 1 kg of soil. So the improved method has a higher efficiency compared with the methods of Dolbin and Romanenko-Hudzhabidze according to the following indicators: the number of positive samples by 5 and 20&nbsp;%; the number of detected oocysts in the studied samples was 26.21 and 53.45&nbsp;%; the average number of detected oocysts per 1 kg of soil was 22.33 and 41.81&nbsp;% (p &lt;0.01), respectively. At the same time, the method turned out to be more effective than the techniques of Dolbin and Romanenko-Hudzhabidze in terms of the minimum indicators of the identified invasive elements by 60 and 86.67&nbsp;%, and maximum - by 21.6 and 28.0&nbsp;%, respectively.

Parasitic Diseases that can Infect Travelers to Africa.

Travel is important in the spread of diseases, and the number of travelers is increasing daily. Therefore, the importance of the diseases that occur during or after travel is increasing. In underdeveloped countries in particular, parasitic diseases are epidemic or endemic, and these diseases lead to high numbers of deaths. People traveling from developed to underdeveloped countries have a higher risk of transmission of parasitic diseases during travel. Fifteen percent of the world's population lives in Africa. In terms of geography, economics, and development, the continent is divided into four regions: East Africa, South Africa, North Africa, and West Africa. In recent years, international travels to Africa have been increasing. During these travels, there is a risk of contracting parasitic diseases, such as malaria, schistosomiasis, trypanosomiasis (African sleeping disease), onchocerciasis, lymphatic filariasis, and leishmaniasis. Before traveling to Africa, it is vital to take measures against diseases in the region.

Parasitic Infections in Individuals Travelling to America and Precautionary Measures.

Over the past decade, the number of international travels has increased. Hence, the risk of transmission of parasitic diseases has also increased. One of the risk infections is malaria; Plasmodium vivax and P. falciparum species can be transmitted. The distribution of leishmaniasis cases has been reported from the south of USA to the north of Argentina. Approximately 57,000 cases of cutaneous and mucocutaneous leishmaniasis occur annually, and approximately 4000 visceral leishmaniasis cases are observed. It is reported that Chagas disease is endemic in 21 countries, and approximately 6 million people are affected every year. In this continent, 25 million people are at a risk of schistosomiasis, and most (90%) are living in Brazil. According to the World Health Organization, individuals travelling to Ecuador, Colombia, Brazil, Guatemala, Mexico, and Venezuela are at a risk of onchocerciasis as well as infecting approximately 12.6 million individuals with lymphatic filariasis (80% in Haiti). Significant mortality and morbidity can be observed in cases where necessary precautions are not taken in individuals travelling to these regions and where appropriate prophylactic drugs are not administered.

Comparison of gastrointestinal parasite communities in vervet monkeys.

Globally, habitat degradation is accelerating, especially in the tropics. Changes to interface habitats can increase environmental overlap among nonhuman primates, people, and domestic animals and change stress levels in wildlife, leading to changes in their risk of parasite infections. However, the direction and consequences of these changes are unclear, since animals may benefit by exploiting human resources (e.g., improving nutritional health by eating nutritious crops) and decreasing susceptibility to infection, or interactions with humans may lead to chronic stress and increased susceptibility to infection. Vervet monkeys are an excellent model to understand parasitic disease transmission because of their tolerance to anthropogenic disturbance. Here we quantify the gastrointestinal parasites of a group of vervet monkeys (Chlorocebus aethiops) near Lake Nabugabo, Uganda, that frequently overlaps with people in their use of a highly modified environment. We compare the parasites found in this population to seven other sites where vervet monkey gastrointestinal parasites have been identified. The vervets of Lake Nabugabo have the greatest richness of parasites documented to date. We discuss how this may reflect differences in sampling intensity or differences in the types of habitat where vervet parasites have been sampled.