Incidence Of Giardiasis Research Articles

Travel-related giardiasis: Incidence and time trends for various destination countries.

Giardiasis is a common gastrointestinal illness in travellers. Data on the actual giardiasis risk of travellers to different travel destinations is scarce. We aim to estimate the risk of giardiasis in travellers from Germany by destination country and region. We analysed travel-related giardiasis cases, their countries and regions of exposure and the age and sex distribution of cases reported in 2014-2019 in Germany. We defined a travel-related giardiasis case as a laboratory-confirmed (i.e. positive microscopy, antigen test or nucleic acid test) symptomatic individual with outbound travel abroad within 3-25days before symptom onset. Based on the number of reported cases per exposure country and UNWTO travel data for Germany, we calculated the number of travel-related giardiasis cases per 100 000 travellers and compared the incidence in 2014-2016 and 2017-2019 to identify potential trends. In 2014-2019, 21 172 giardiasis cases were reported in Germany, corresponding to an overall incidence of 4.3 per 100 000 population. Of all cases, 6879 (32%) were travel-related with a median age of 34 (interquartile range (IQR): 25-50), 51% were male. Southern Asia was the most frequently reported exposure region and had the highest incidence in travellers (64.1 per 100 000 returning travellers) in 2017-2019, followed by Latin America (19.2) and Sub-Saharan Africa (12.9). We observed statistically significant decreasing trends for Southern Asia and Sub-Saharan Africa. Latin America was the only region with a statistically significant increasing trend. Almost one-third of recent giardiasis cases in Germany were travel-related. Giardiasis incidence in travellers differs greatly depending on the destination region. Decreasing trends in many regions might be due to improvements in food hygiene or travel conditions. Our results may inform medical consultation pre and post patient's travel.

Individual and Community-Level Risk Factors for Giardiasis in Children under Five Years of Age in Pakistan: A Prospective Multi-Regional Study.

This study aimed to estimate the prevalence of Giardia lamblia infection and identify associated risk factors at both individual and community levels in a pediatric population in different agroecological zones of Khyber Pakhtunkhwa, Pakistan. A community-based cross-sectional study was conducted from March to December 2022. Using stratified sampling, 1026 households were recruited from nine agroecological zones. Stool samples were collected from 1026 children up to the age of five years and processed for detection of Giardia using a commercial ELISA kit. Data on potential risk factors were collected using a pre-structured questionnaire. A multivariable logistic regression model was used to identify risk factors associated with giardiasis. The study found that the prevalence of giardiasis in the study area was 3.31%. Children aged 13-24 months were found to be at higher risk for giardiasis. Illiterate mothers and fathers attending daycare institutions/kindergartens, mothers not practicing hand washing during critical times, households with companion animals, and homes where stray dogs/cats enter were identified as predictors of giardiasis at the individual level. Children living in sub-mountain valleys use un-piped water, inadequate domestic water storage vessels, drink un-boiled or unfiltered water, live near rubbish heaps or un-paved streets/pathways, and have unimproved latrine facilities were identified as risk factors of giardiasis at the community level. The study highlights the need for integrated intervention approaches at both individual and community levels to reduce the incidence of giardiasis in Khyber Pakhtunkhwa, Pakistan. Interventions aimed at promoting behavioral change and providing safe and adequate water sources, combined with individual-level interventions such as hand washing and awareness of giardiasis prevention methods, would be critical to addressing this health concern. Inter-sectoral collaboration between the health sector and other sectors would also be necessary to achieve meaningful progress in reducing the incidence of giardiasis in resource-limited areas.

Environmental Factors Associated with Cryptosporidium and Giardia.

Environmental factors significantly influence the transmission of intestinal protozoan diseases. Cryptosporidiosis and giardiasis are important zoonotic diseases characterized by diarrhea, and are mainly water or foodborne diseases caused by fecal-borne oocysts. The One Health approach effectively addresses environmentally influenced zoonotic diseases. However, the impact of environmental factors on the survival of Cryptosporidium/Giardia (oo)cysts or disease transmission is mostly uncharacterized. Associations between cryptosporidiosis and giardiasis incidence and environmental variables (e.g., climatic conditions, soil characteristics, and water characteristics) have been reported; however, the identified relationships are not consistently reported. Whether these are country-specific or global observations is unclear. Herein, we review the evidence for the influence of environmental factors on Cryptosporidium/Giardia and corresponding diseases from three perspectives: climatic, soil, and water characteristics. The (oo)cyst concentration or survival of Cryptosporidium/Giardia and the incidence of corresponding diseases are related to environmental variables. The associations identified varied among studies and have different levels of importance and lag times in different locations. This review summarizes the influence of relevant environmental factors on Cryptosporidium/Giardia from the One Health perspective and provides recommendations for future research, monitoring, and response.

Incidence of Giardiasis Among Population at Wasit Province

Giardia lamblia, an intestinal flagellate parasite is widely prevalent in humans worldwide. A total of 100 stool samples from diarrhoeal patients during three months ( October, November , and December, 2011) were examined by direct smear and lugol’s iodine techniques to investigate Giardia lamblia parasite . The total human patients involved in this study were divided into five age groups . The overall prevalence of G.lamblia infection was 22%. The highest infection appeared the in age group (1-10) years old, and the lowest was in the age group (11-20) years old. Males were highly infected 26 % (13/50) than females 16% (9/50) in patient groups.

Prevalence of Giardia lamblia among children in Sulaimani city, Iraq

Intestinal protozoan parasites Giardia lamblia (G.L) (Giardia duodenalis, G. lamblia, or G. intestinalis) is a flagellated zoonotic parasite are extremely common in impoverished nations, posing major public health risks. The majority of Giardia lamblia infections are asymptomatic. However, sometime abdominal pain, diarrhea, and fever are the most common clinical symptoms of giardiasis, especially in children. The aim of this study was to investigate the prevalence of G.L among children in Sulaimani city, North of Iraq. This study was conducted from January to April 2022. The incidence of giardiasis was investigated in Jamal Ahmad Rashid Pediatric Teaching Hospital. A total of (6600) samples from general stool exam (GSE) by direct microscopic examination were studied. Male and Female, Personal Hygiene, and Eating Habits were all investigated in order to identify a link between giardiasis prevalence and these characteristics. Out of 6600 samples of GSE examined, 19 (0.2%) were positive for G.L. The prevalence rate of G.L among males were 11 (57.9%) which is higher than female 8 (42.1%). In prevalence of G.L according to months, the highest prevalence rate was recorded in April and the lowest prevalence rate were in January and February for both (males and females).

Частота, предиктори та критерії діагностики лямбліозу в дітей

Актуальність. Поширеність лямбліозу серед дітей становить 355 випадків на 100 тис. дитячого населення, при цьому 80 % випадків інвазії припадає на дітей, молодших 14 років. Актуальність високої поширеності протозойної патології у дітей зумовлена тим, що її прояви часто маскуються під різні патологічні стани. Мета. Вивчення частоти, предикторів і критеріїв діагностики лямбліозу в дітей. Матеріали та методи. Дизайн дослідження — контрольоване рандомізоване. У дослідження включені діти, хворі на лямбліоз (n = 55), віком від 3 до 17 років. Група порівняння становила 30 практично здорових дітей. Обстеження хворих і набір матеріалу проводили на базі поліклінічного та гастроентерологічного відділень КМУ «Чернівецька обласна дитяча клінічна лікарня» впродовж 2014–2016 років. Лабораторні та інструментальні дослідження проводилися в українсько-німецькій лабораторії «Букінтермед» та лабораторії дитячого гастроентерологічного центру «Дігест». Використані непрямі (серологічний метод, макроскопія слизової оболонки ДПК при ендоскопічному дослідженні, непрямі ознаки лямбліозу в дуоденобіоптатах) та прямі (мікроскопія калу, дуоденального вмісту, виявлення вегетативних форм лямблій у дуоденобіоптатах під час гістологічного дослідження) методи дослідження. Проводилося анкетування батьків. Відмінності вважалися статистично вірогідними при досягнутому рівні значущості р ≤ 0,05. Результати. Позитивний результат отримано у 29 із 565 обстежених на лямблії осіб (5,1 %). Найчастіше потребували дообстеження на наявність лямблій діти, хворі на хронічну патологію верхніх відділів шлунково-кишкового тракту та гепатобіліарної системи, з алергічними реакціями, дисбіозом кишечника та стійкою еозинофілією крові. Діти, хворі на лямбліоз, вірогідно частіше хворіли на супутню патологію, ніж діти групи порівняння (р < 0,05). У 41,4 % випадків діти проживали в умовах, що не відповідали задовільним, не завжди дотримувалися правил гігієни. Нами встановлені несприятливі фактори антенатального (стан здоров’я матері під час вагітності, перебіг вагітності, наявність професійних шкідливостей), інтранатального (передчасні пологи, стимуляція пологової діяльності та кесарів розтин, пологова травма й асфіксія у дітей) та постнатального (тривалість грудного вигодовування, супутня патологія) періодів. Усі гістологічні ознаки можуть бути використані як імовірні критерії лямбліозу в дітей, однак із найбільшою вірогідністю можна використовувати таку ознаку, як наявність ділянок десквамації епітелію ворсинок з одночасним переважанням в інфільтраті еозинофілів і тучних клітин. Висновки. Частота лямбліозу у дітей і підлітків дорівнює 5,1 %. Встановлені нами анамнестичні фактори (соціальні, гігієнічні, медико-біологічні) можна розглядати як предиктори розвитку лямбліозу в дітей. У клініці лямбліозу домінує ураження травного тракту — у 96,3 % дітей. Для підвищення точності діагностики лямбліозу в дітей необхідно використовувати комплекс прямих і непрямих методів діагностики.

Current state of infection and prevalence of giardiasis in Malaysia: a review of 20 years of research.

BackgroundGiardiasis is a neglected parasitic zoonotic disease caused by Giardia duodenalis that is often overlooked despite the damage inflicted upon humans and domestic/wild animals. Lack of surveillance studies, low sensitivity of diagnostic tools, and resistance to giardiasis treatment add to the challenge in managing giardiasis, leaving a gap that continues to render giardiasis a silent threat to public health worldwide. This situation is not much different in Malaysia, where giardiasis remains a public health problem, especially in the indigenous communities. Realizing the existence of gaps in the literature and information on giardiasis in Malaysia, this review aims to revisit and update the situation of giardiasis in Malaysia based on articles published in 20 years from 2000 to 2020, providing estimates on the incidence of giardiasis in humans, animals, and the environment, which may inform efforts to prevent and control the impact of giardiasis in the country.MethodologyWe searched PubMed, Science Direct, and Scopus using MeSH terms and text keywords “Giardia duodenalis OR Giardia intestinalis OR Giardia lamblia OR intestinal protozoa AND Malaysia”. Information was collected from all giardiasis reports published between 2000 and 2020.ResultsGiardiasis in Malaysia is more prevalent among the poorest segments of the population, namely the indigenous communities and people living in densely populated areas such as slums and prisons, due to low standard of personal hygiene, unsafe water resources, and improper sanitation. While the prevalence data is hugely dependent on microscopic fecal examination in epidemiological studies of giardiasis, current studies mostly focused on species identification and genotype distribution by multilocus genotyping. Thus far, the outbreak of giardiasis has not been reported in the country, but the disease was found to be significantly associated with stunting, wasting, and malnutrition among children of the indigenous communities. Surveillance studies also discovered the simultaneous presence of Giardia in the animal-environments, including wild animals, ruminants, and treated and untreated water. The data collected here will be a useful addition to the literature body on giardiasis in Malaysia, which can be exploited in efforts to prevent and control the impact of giardiasis in the country.ConclusionsThe last 10 years have shown that the overall mean rate of giardiasis in Malaysia is quite encouraging at 13.7%. While this figure appears to be declining, there has been a slight increase in the prevalence of underweight, stunting, and wasting among rural children in 2019. The fact that giardiasis is linked to long-term childhood developmental problems, indicates that addressing and providing better disease control against giardiasis should be a priority in supporting the national agenda to achieve Malaysia Global Nutrition Targets by 2025.

Examination of Giardia intestinalis with Direct Microscopy and Direct Fluorescent Antibody in Patients with Diarrhea.

In this study, our objective was to compare direct microscopic examination and direct fluorescence antibody (DFA) method for Giardia diagnosis in stool samples and to evaluate the possible risk factors related to Giardia infections. Stool samples of 185 patients with diarrhoea collected between June 2019 and July 2019 in Erzurum Yakutiye Research Hospital were included in the study. Microscopic examination of the samples was performed with native-lugol, and they were subsequently scanned by the indirect fluorescent assay microscope using the DFA method at 100-200X magnification. In addition, all patients filled a questionnaire prepared to determine the possible risk factors related to Giardia infection. The age of the 185 participating patients who belonged to different groups was between 0 and 94 years. Giardia spp. cysts were detected in five stool samples (2.7%) using direct microscopic examination. Nine samples (4.9%) were DFA-positive. The incidence of giardiasis was noted to be 7.5% in children, 3.8% in adults, 7.3% in people living in rural areas, 2.9% in people living in urban areas, 10% in people having pets and 4.2% in people who do not have pets. By taking the DFA method as a reference, the sensitivity and specificity of the microscopic examination were found to be 44.4% and 99.4%, respectively. The Giardia positivity rate was higher in children, those living in rural areas, those having pets and those using well water as drinking water.

Clinical characteristics versus human leukocyte antigen class-II DRB1 alleles profiles and fecal calprotectin level in Giardia lamblia-infected children

Background:Giardia lamblia is a global enteric protozoan causing giardiasis, a disease characterized by different clinical presentations ranging from loss of appetite, abdominal pain, steatorrhea, nausea, vomiting to severe malabsorption syndrome, but the majority of infected children are asymptomatic, especially in developing countries. The clinical outcome may be associated with fecal calprotectin released in the bowel in case of inflammation and human leukocyte antigen (HLA) class-II DRB1 alleles that play a crucial role in the immune system. Objectives: To reveal any association between fecal calprotectin and the development of symptomatic or asymptomatic giardiasis. Also, to highlight the influence of HLA class-II DRB1 alleles on clinical manifestations of G. lamblia-infected children. Subjects and Methods: The study included 160 children: 80 healthy children (control), 40 Giardia-positive children with gastrointestinal symptoms (symptomatic group), and 40 Giardia-positive children without gastrointestinal manifestations (asymptomatic group). Fecal calprotectin was measured using ELISA, and HLA class-II was typed by PCR. Results: The commonest presentation of giardiasis was abdominal pain. Fecal calprotectin level was elevated (141.40±67.7-183±48.21 µg/gm) in children with giardiasis, mainly among asymptomatic group. HLA class-II DRB1*03:01 and *13:01 alleles were significantly associated with incidence of giardiasis (P<0.0005). A significant association of the heterozygous allotype HLA-DRB1*03:01/03:02 was recorded with giardiasis manifestations, mainly abdominal pain (P=0.026). Conclusion: Fecal calprotectin can be used as a marker of G. lamblia-induced intestinal inflammation. HLA class-II DRB1*03 and DRB1*13 alleles likely underlie clinical variability of giardiasis. This association may clarify why giardiasis does not occur in significant number of children exposed to the parasite.

An update on the incidence of human giardiasis in Scotland, 2011\u20132018

BackgroundGiardia duodenalis is one of the most common parasites in the UK to cause diarrhoeal illness. Giardiasis is likely to be significantly under-reported in the UK as laboratory testing is largely based on examining stool samples from individuals with a recent travel history. This results in the majority of locally-acquired cases going undetected. To increase awareness of giardiasis, we describe data gathered from cases reported within Scotland during 2011–2018.MethodsAll of the 21 Scottish National Health Service (NHS) diagnostic microbiology laboratories performed microscopy examination to detect Giardia cysts in stools, from mostly travel-related cases. The exception was one laboratory that implemented an antigen-based enzyme immunoassay in 2015. This resulted in every submitted stool being tested for Giardia. Laboratory-confirmed cases of giardiasis were reported to Health Protection Scotland (HPS) via the Electronic Communication of Surveillance in Scotland (ECOSS) during the eight-year period. Data for calculating the incidence per 100,000 of the population were obtained from the National Records of Scotland mid-2018 population estimates in Scotland.ResultsA total of 1631 Scottish cases were reported during 2011–2018 (8-year mean: 204; range: 166–269). National Health Service Grampian, Borders and Lothian reported the highest incidence of Giardia (9.8, 7.5 and 6.7 per 100,000, respectively), all of which were above the Scottish mean incidence (3.8 per 100,000). Following the implementation of antigen testing in NHS Grampian during 2015, reports significantly increased 3.6-fold (P = 0.005). The highest incidence of giardiasis occurred in the 20–49 years age group (mean 5.4 per 100,000). Of interest, the mean incidence of giardiasis was significantly higher in males than in females (4.8 versus 3.1 per 100,000, respectively; P < 0.0001).ConclusionsThis report highlights the need to capture enhanced information on every laboratory-confirmed case of giardiasis to gain a better understanding of the local sources and transmission pathways occurring in Scotland. In addition, implementing sensitive, automated technologies across UK NHS diagnostic microbiology laboratories to permit the efficient, routine testing of every submitted stool for Giardia, should be encouraged to ensure all cases are identified and treated appropriately.

Survey of Giardiasis Symptoms in Patients Referred to Health Care Centers in Zahedan, South-Eastern Iran, 2017-2018

Background: There are many pathogenic intestinal parasites in humans, one of which is Giardia lamblia. This parasite has a variety of clinical symptoms in individuals. Poor health, weather conditions, and inappropriate lifestyle are all factors contributing to the high incidence of giardiasis. Objective: Based on factors influencing the prevalence of giardiasis in the region, this study was performed on subjects referred to Zahedan health care centers. Materials and Methods: A total of 671 stool specimens of subjects who referred between March 2017 and October 2018 were examined using direct and formalin ether concentration techniques. All demographic and clinical data in questionnaires were recorded. Data were analyzed using X2 test to determine any differences in the prevalence of giardiasis and clinical symptoms between different age groups. Results: Of 671 samples, 346 (51.1%) were positive. The most common complaint among participants was abdominal pain (64.1%), followed by diarrhea (53.7%), abdominal cramps (44.7%), nausea (32.6%), weight loss (30.9%), anorexia (26.8%), headache (22.2%), fatigue (14.1%), and fever (13.2%). Most of the clinical symptoms such as abdominal pain, abdominal cramp, weight loss, and headache were reported in females, and the results of chi-square test showed a significant difference (P&lt;0.05). The age group of 1-12 years had the highest percentage of infection (49.42%). The data indicated that the highest rate of infection was observed in this group, showing a significant difference in comparison with other age groups (P&lt;0.05). Conclusion: The results of this study showed that in addition to health education, preventing the transmission of parasites to children would also be necessary.

Epidemiology of human giardiasis in Romania: A 14 years survey

Giardia spp. is the most common intestinal protozoan (causing gastrointestinal illness) and the most frequent cause of parasitic gastroenteritis in humans and animals worldwide. The aim of this study was to highlight new data in a specific area regarding clinical presentation and epidemiological prevalence over a long period of time. Patients (a total number of 54,623 patients) admitted in a tertiary center for infectious diseases serving a county for a period of 14 years were tested for infection with Giardia. Positive cases were recorded through analyzing the clinical complaints, the month of incidence and the demographic area from which the patients came from. Longitudinal trends have been evaluated. The incidence of giardiasis among the tested patients was 4.47%. A decreasing trend was observed regarding the annual incidence. Patients between the ages of 15 and 44 presented most commonly giardiasis, especially those from urban areas and women. The most common symptoms are loss of appetite (71.24%) and abdominal pain (69.07%). The highest monthly incidence was quoted in July (10.65%), August (10.49%) and June (10.20%). This epidemiological study allows a better knowledge of the infection with Giardia spp. It gives the long-term changes in demographic characteristics of the infected patients in a specific area and the monthly incidence.

GIARDIASIS IN THE KRASNODAR REGION IN THE PERIOD FROM 2013–2018

The analysis of statistical data of the Federal service of state statistics of Krasnodar region and the Republic of Adygea to the extent of years 2013–2018. We analyzed three groups of people of different ages. Group 1: children up to 14 years old; group 2: teenagers 15–17 years old; group 3: adults of 18 years and older. So, in the first group for one thousand examined 55.1 patients were revealed in 2013; in 2014 – 55.8; in 2016 – 51.2; in 2018 – 51.8. From these data it can be seen that the peak incidence was in 2014, then there is a decline, and in 2016 the number of patients with giardiasis among the child population begins to increase. In the second group, the low incidence is shown in 2013 – 26.8 people per one thousand examined, in 2015 – 27.4; in 2016. – 32.4, i.e. peak of invasion, in 2017 – 31.2; in 2018 – 28.5, that is, there is an increase in morbidity in 2015, 2016 and then a decline in the incidence of giardiasis. In the third group, the calculation led to a hundred thousand surveyed, and the growth of the infestation was observed; in 2016 – 10.2 i.e., the peak of cases of giardiasis, followed by a slight decline. In 2017 – 9.0; in 2018 - 8.0. From the above data we can see that the incidence of children's population is much higher than that of adolescents and much lower in the adult generation.

Study the Relation between the Incidence of Giardiasis and Some Epidemiological Factors in Some Regions of Baghdad City

In this work, the incidence of giardiasis was investigated in some regions of Baghdad. Different factors were studied such as age, gender, personal hygiene and eating habits, in order to find its correlation with the prevalence of giardiasis. The study was carried out during the period of April 2014 till March 2015. During this period a total of 375 samples have been examined. The total rate of infection was 68/375 (18.13%. The most frequent noticed clinical symptoms in giardiasis cases are abdominal pain 60.97%, diarrhea 41.46% and fever 35%. For the studied factors, each of the age, personal hygiene and eating habits showed a relation with the incidence of giardiasis.

The Influence of Climate and Livestock Reservoirs on Human Cases of Giardiasis

Giardia duodenalis is an intestinal parasite which causes diarrhoeal illness in people. Zoonotic subtypes found in livestock may contribute to human disease occurrence through runoff of manure into multi-use surface water. This study investigated temporal associations among selected environmental variables and G. duodenalis occurrence in livestock reservoirs on human giardiasis incidence using data collected in the Waterloo Health Region, Ontario, Canada. The study objectives were to: (1) evaluate associations between human cases and environmental variables between 1 June 2006 and 31 December 2013, and (2) evaluate associations between human cases, environmental variables and livestock reservoirs using a subset of this time series, with both analyses controlling for seasonal and long-term trends. Human disease incidence exhibited a seasonal trend but no annual trend. A Poisson multivariable regression model identified an inverse association with water level lagged by 1 month (IRR = 0.10, 95% CI 0.01, 0.85, P < 0.05). Case crossover analysis found varying associations between lagged variables including livestock reservoirs (1 week), mean air temperature (3 weeks), river water level (1 week) and flow rate (1 week), and precipitation (4 weeks). This study contributes to our understanding of epidemiologic relationships influencing human giardiasis cases in Ontario, Canada.

Giardia intestinalis assemblage E as an Emerging Zoonosis in Livestock

&lt;p&gt;&lt;em&gt;Giardia intestinalis&lt;/em&gt; is a gastrointestinal parasite causing giardiasis that infects animals and humans. Giardiasis generates diarrhea, malabsorption, decreased body weight and milk production, dehydration, and mortality especially in young animals. This paper describes &lt;em&gt;G. intestinalis&lt;/em&gt; assemblage E in humans and livestock, including molecular identification and disease distribution. The incidence of giardiasis in humans and livestock has been reported in some countries, particularly in young host living under poor sanitation and hygiene. Based on genotype, the parasite is divided into eight assemblages (A-H) and some infect specific hosts. At the moment, assemblage E is known as genotype that infects animal. This statement is controversial since assemblage E was also detected in humans who contacted with animals. This condition assumes that assemblage E is an emerging zoonosis that needs special attention.&lt;/p&gt;

Estimating and mapping the incidence of giardiasis in Colombia, 2009–2013

Giardiasis is one of the most common intestinal infections in the world. There have been no national studies on the morbidity of giardiasis in Colombia. In this study, incidence rates of giardiasis were estimated for the years 2009-2013. An observational, retrospective study of the giardiasis incidence in Colombia, 2009-2013, was performed using data extracted from the personal health records system (Registro Individual de Prestación de Servicios, RIPS). Official population estimates from the National Department of Statistics (DANE) were used for the estimation of crude and adjusted incidence rates (cases/100000 population). During the period studied, 15851 cases were reported (median 3233/year; 5-year cumulated crude national rate of 33.97 cases/100000 population). Of these, 50.3% were female; 58.4% were <10 years old and 14.8% were 10-19 years old. By region, 17.7% were from Bogotá (10.07 cases/100000 population, 2009), 10.9% from Antioquia (9.42, 2009), 8.6% from Atlántico (15.67, 2009), and 6.5% from Risaralda (33.38, 2009). Cases were reported in all departments (even insular areas). As giardiasis is neglected in many countries, surveillance is not regularly undertaken. Despite its limitations, this study is the first attempt to provide estimates of national giardiasis incidence with consistent findings regarding affected age groups and geographical distribution.

Dientamoeba fragilis, One of the Neglected Intestinal Protozoa.

Dientamoeba fragilis is a single-celled protozoan, closely related to the trichomonads. Reported worldwide as causing human gastrointestinal symptoms, D. fragilis is very common and is second only to Blastocystis spp. Dientamoebiasis equals or exceeds the incidence of giardiasis. This minireview includes diagnostic options, clinical relevance, therapy, an animal model, the confirmed cyst stage, and sequencing data. The development of a rodent model, fulfilling Koch's postulates, and the confirmation of a cyst stage have clarified transmission routes, including fecal-oral transmission. The prevalence of D. fragilis varies between 0% to over 82%; results depend on the geographic location, group studied, and diagnostic methods used.

Giardiasis in the United States - an epidemiologic and geospatial analysis of county-level drinking water and sanitation data, 1993-2010.

Giardiasis is the most commonly reported intestinal parasitic infection in the United States. Outbreak investigations have implicated poorly maintained private wells, and hypothesized a role for wastewater systems in giardiasis transmission. Surveillance data consistently show geographic variability in reported giardiasis incidence. We explored county-level associations between giardiasis cases, household water and sanitation (1990 census), and US Census division. Using 368,847 reported giardiasis cases (1993-2010), we mapped county-level giardiasis incidence rates, private well reliance, and septic system reliance, and assessed spatiotemporal clustering of giardiasis. We used negative binomial regression to evaluate county-level associations between giardiasis rates, region, and well and septic reliance, adjusted for demographics. Adjusted giardiasis incidence rate ratios (aIRRs) were highest (aIRR 1.3; 95% confidence interval 1.2-1.5) in counties with higher private well reliance. There was no significant association between giardiasis and septic system reliance in adjusted models. Consistent with visual geographic distributions, the aIRR of giardiasis was highest in New England (aIRR 3.3; 95% CI 2.9-3.9; reference West South Central region). Our results suggest that, in the USA, private wells are relevant to giardiasis transmission; giardiasis risk factors might vary regionally; and up-to-date, location-specific national data on water sources and sanitation methods are needed.

Giardiasis in North West England: faecal specimen requesting rates by GP practice.

Many cases of giardiasis in the UK are undiagnosed and among other things, diagnosis is dependent upon the readiness of GPs to request a specimen. The aim of this study is to assess the rate of specimens requested per GP practice in Central Lancashire, to examine the differences between GP practices and to estimate the pattern of unexplained spatial variation in the practice rate of specimens after adjustment for deprivation. To achieve this, we fitted a set of binomial and Poisson regression models, with random effects for GP practice. Our analysis suggests that there were differences in the rate of specimens by GP practices (P < 0·001) for a single year, but no difference in the proportion of positive tests per specimen submitted or in the rate of positive specimens per practice population. There was a difference in the cumulative rate of positive specimens per practice population over a 9-year period (P < 0·001). Neither the specimen rate per practice for a single year nor the cumulative rate of positive specimens over multiple years demonstrated significant spatial correlation. Hence, spatial variation in the incidence of giardiasis is unlikely to be confounded by variation in GP rate of specimens.