Presence of Giardia lamblia in stools of six- to 18-month old asymptomatic Malawians is associated with children's growth failure.

AIM: Despite high pathogen burden and malnutrition in low-income settings, knowledge on relationship between asymptomatic viral or parasitic infections, nutrition and growth is insufficient. We studied these relationships in a cohort of six-month-old Malawian infants. METHODS: As part of a nutrient supplementation trial for 12 months, we documented disease symptoms of 840 participant daily and anthropometric measurements every three months. Stool specimens were collected every six months and analysed for Giardia lamblia, Cryptosporidium species and enterovirus, rotavirus, norovirus, parechovirus and rhinovirus using polymerase chain reaction (PCR). The prevalence of the microbes was compared to the children's linear growth and the dietary. RESULTS: The prevalence of the microbes was similar in every intervention group. All age groups combined, children negative for G. lamblia had a mean standard deviation (SD) of -0.01 (0.49) change in length-for-age Z-score (LAZ), compared to -0.12 (0.045) among G. lamblia positive children (difference -0.10, 95% CI -0.21 to -0.00, p = 0.047). The LAZ change difference was also statistically significant (p = 0.042) at age of 18-21 months but not at the other time points. CONCLUSION: Asymptomatic G. lamblia infection was mainly associated with growth reduction in certain three-month periods. The result refers to the chronic nature of G. lamblia infection.

Homeopathic treatment as an alternative prophylactic to minimize bacterial infection and prevent neonatal diarrhea in calves.

Bovine neonatal diarrhea is common due low immunity in newborn calves, poor management (or absence) of sanitary barriers, and other factors. Newborn calves with diarrhea in the first days of life suffer failure to thrive and may die if left untreated. The aim of this study was to evaluate whether prophylactic administration of a homeopathic product (Dia 100®) can control bovine neonatal diarrhea in calves born on a farm with substantial sanitary challenges. We counted total bacteria and protozoan parasites in fecal samples. We measured serum glucose, total protein, globulin, albumin, cholesterol and triglycerides on days 1, 7 and 14 of life. Twenty newborn calves were maintained in individual stalls, and were divided in two groups: ten untreated animals (control) and ten animals treated with Dia 100®. Fecal consistency was evaluated daily. We diagnosed diarrhea in five animals in the treated group, and in all animals from the control group. Infections with Escherichia coli and Giardia duodenalis were identified as the responsible organisms. The E. coli count was low in the treatment group on day 7 of life compared with the control group. Antibiotics were given to eight animals in the control group, and to two animals in the treatment group. On day of life 7, serum levels of total protein and globulins were higher in the control group, but were lower on day 14. Serum levels of glucose and triglycerides were greater in treated animals on days 7 and 14, suggesting that the homeopathic product contributes to improvement of intestinal health and absorption and nutrients. We conclude that Dia 100® controls diarrhea with 50% of efficacy, and reduces antibiotic utilization.

Intestinal parasites from the 2nd-5th century AD latrine in the Roman Baths at Sagalassos (Turkey).

The aim of this research was to determine the species of intestinal parasite present in a Roman Imperial period population in Asia Minor, and to use this information to improve our understanding of health in the eastern Mediterranean region in Roman times. We analyzed five samples from the latrines of the Roman bath complex at Sagalassos, Turkey. Fecal biomarker analysis using 5ß-stanols has indicated the feces were of human origin. The eggs of roundworm (Ascaris) were identified in all five samples using microscopy, and the cysts of the protozoan Giardia duodenalis (which causes dysentery) were identified multiple times in one sample using ELISA. The positive G. duodenalis result at Sagalassos is particularly important as it represents the earliest reliable evidence for this parasite in the Old World (i.e. outside the Americas). As both these species of parasite are spread through the contamination of food and water by fecal material, their presence implies that Roman sanitation technologies such as latrines and public baths did not break the cycle of reinfection in this population. We then discuss the evidence for roundworm in the writings of the Roman physician Galen, who came from Pergamon, another town in western Asia Minor.

Ocorrência de Giardia lamblia em alfaces (Lactuva sativa) comercializadas nos municípios de Chapecó e Xanxerê, SC / Occurrence of Giardia lamblia in lettuces (Lactuca sativa) marketed in the municipalities of Chapeco and Xanxere, SC

A Organização Mundial da Saúde alerta sobre a grande quantidade de doenças parasitárias na população mundial e comenta que uma das fontes de infecção humana é através da ingestão de alimentos contaminados. A Giardia lamblia é um protozoário que pode ser transmitido através do consumo de hortaliças contaminadas, quando produzidas e comercializadas de forma inadequada. A contaminação desses produtos pode ocorrer durante o seu cultivo ou na sua venda em mercados e feiras, quando manipulada por vendedores infectados. O objetivo desse estudo foi coletar alfaces (Lactuva sativa) comercializadas nos municípios de Chapecó e Xanxerê, Santa Catarina e identificar a presença de Giardia lamblia nas mesmas. Foram coletadas 33 amostras e posteriormente processadas através da técnica de Faust e col. para a detecção de Giardia lamblia. Das 33 amostras, em 18,18% (6/33) detectou-se a presença de cistos do protozoário. Um manejo correto da adubação e da irrigação utilizados para o cultivo das hortaliças e uma boa manipulação dos mesmos, garante um alimento de alta qualidade e evita prejuízos à saúde pública, evitando dessa forma a presença de zoonoses, como a Giardíase, que afeta principalmente crianças e pessoas imunossuprimidas.

The World Health Organization warns of the large amount of parasitic diseases in the world population and said that one of the main sources of human infection is through the ingestion of contaminated food. Giardia lamblia is a protozoan that can be transmitted through consumption of contaminated vegetables, when produced and marketed improperly. The contamination of these products can occur during cultivation or in sale, in markets and fairs, when manipulated by infected sellers. The aim of this work were collect lettuces (Lactuva sativa) marketed in Chapecó and Xanxerê municipalities, Santa Catarina State, Brazil and to check the presence of Giardia lamblia under the same. Thirty three samples were collected and then processed through the Faust et al. technique for the detection of Giardia lamblia. Of the 33 samples, 18.18% (6/33) were positive for the presence of protozoan cysts. Proper management of fertilization and irrigation used for the cultivation of vegetables and a good handling them ensures a high quality food and prevents damage to public health; what prevents the presence of zoonoses such as giardiasis, which mainly affects children and immunosuppressed people.

Multi-parallel qPCR provides increased sensitivity and diagnostic breadth for gastrointestinal parasites of humans: field-based inferences on the impact of mass deworming.

BACKGROUND: Although chronic morbidity in humans from soil transmitted helminth (STH) infections can be reduced by anthelmintic treatment, inconsistent diagnostic tools make it difficult to reliably measure the impact of deworming programs and often miss light helminth infections. METHODS: Cryopreserved stool samples from 796 people (aged 2-81 years) in four villages in Bungoma County, western Kenya, were assessed using multi-parallel qPCR for 8 parasites and compared to point-of-contact assessments of the same stools by the 2-stool 2-slide Kato-Katz (KK) method. All subjects were treated with albendazole and all Ascaris lumbricoides expelled post-treatment were collected. Three months later, samples from 633 of these people were re-assessed by both qPCR and KK, re-treated with albendazole and the expelled worms collected. RESULTS: Baseline prevalence by qPCR (n = 796) was 17 % for A. lumbricoides, 18 % for Necator americanus, 41 % for Giardia lamblia and 15% for Entamoeba histolytica. The prevalence was <1% for Trichuris trichiura, Ancylostoma duodenale, Strongyloides stercoralis and Cryptosporidium parvum. The sensitivity of qPCR was 98% for A. lumbricoides and N. americanus, whereas KK sensitivity was 70% and 32%, respectively. Furthermore, qPCR detected infections with T. trichiura and S. stercoralis that were missed by KK, and infections with G. lamblia and E. histolytica that cannot be detected by KK. Infection intensities measured by qPCR and by KK were correlated for A. lumbricoides (r = 0.83, p < 0.0001) and N. americanus (r = 0.55, p < 0.0001). The number of A. lumbricoides worms expelled was correlated (p < 0.0001) with both the KK (r = 0.63) and qPCR intensity measurements (r = 0.60). CONCLUSIONS: KK may be an inadequate tool for stool-based surveillance in areas where hookworm or Strongyloides are common or where intensity of helminth infection is low after repeated rounds of chemotherapy. Because deworming programs need to distinguish between populations where parasitic infection is controlled and those where further treatment is required, multi-parallel qPCR (or similar high throughput molecular diagnostics) may provide new and important diagnostic information.

An integrated microfludic device for culturing and screening of Giardia lamblia.

In vitro culturing of trophozoites was important for research of Giardia lamblia (G. lamblia), especially in discovery of anti-Giardia agents. The current culture methods mainly suffer from lab-intension or the obstacle in standardizing the gas condition. Thus, it could benefit from a more streamlined and integrated approach. Microfluidics offers a way to accomplish this goal. Here we presented an integrated microfluidic device for culturing and screening of G. lamblia. The device consisted of a polydimethylsiloxane (PDMS) microchip with an aerobic culture system. In the microchip, the functionality of integrated concentration gradient generator (CGG) with micro-scale cell culture enables dose-response experiment to be performed in a simple and reagent-saving way. The diffusion-based culture chambers allowed growing G. lamblia at the in vivo like environment. It notable that the highly air permeable material of parallel chambers maintain uniform anaerobic environment in different chambers easily. Using this device, G. lamblia were successfully cultured and stressed on-chip. In all cases, a dose-related inhibitory response was detected. The application of this device for these purposes represents the first step in developing a completely integrated microfluidic platform for high-throughput screening and might be expanded to other assays based on in vitro culture of G. lamblia with further tests.

Evaluation of the therapeutic efficacy of Mentha crispa in the treatment of giardiasis.

It's estimated that around 200 million people are annually infected with Giardia lamblia, making the disease a major cause of morbidity worldwide. The current treatment of giardiasis includes the use of several drugs, among them, herbal medicines formulated with Mentha crispa. Thus, the purpose of this study was to evaluate the therapeutic efficacy of M. crispa in the treatment of giardiasis. The research consisted initially of a cross-sectional study for the selection of subjects with giardiasis. After that, there was a randomized, open, in parallel with active control study, in order to verify the therapeutic efficacy of M. crispa in the treatment of giardiasis. Coprology samples were collected from 1622 patients between May 2005 and May 2007 for a series of parasitological examinations. Ninety-six patients with G. lamblia were selected, which were then distributed randomly into two groups: Secnidazole, consisting of 50 patients treated with 2g of Secnidazole and M. crispa, containing 46 patients treated with 2g of M. crispa. After 7 days, healing was evaluated by enzyme immunoassay in a fresh fecal sample. Additionally, the subjects were questioned about possible adverse effects and answered a questionnaire covering socioeconomic and hydrosanitary issues. The analysis of the clinical trial data showed that the cure rate for the Secnidazole group (84.0%) was significantly higher (P=0.0002) as that verified in the M. crispa group (47.83%). Therefore, the study concludes that, in the dose used in this trial, the effect of M. crispa in the treatment of giardisis is less effective than that of Secnidazole.

Protection against diarrhea associated with Giardia intestinalis Is lost with multi-nutrient supplementation: a study in Tanzanian children.

BACKGROUND: Asymptomatic carriage of Giardia intestinalis is highly prevalent among children in developing countries, and evidence regarding its role as a diarrhea-causing agent in these settings is controversial. Impaired linear growth and cognition have been associated with giardiasis, presumably mediated by malabsorption of nutrients. In a prospective cohort study, we aim to compare diarrhea rates in pre-school children with and without Giardia infection. Because the study was conducted in the context of an intervention trial assessing the effects of multi-nutrients on morbidity, we also assessed how supplementation influenced the relationship between Giardia and diarrhoea rates, and to what extent Giardia modifies the intervention effect on nutritional status. METHODS AND FINDINGS: Data were collected in the context of a randomized placebo-controlled efficacy trial with 2×2 factorial design assessing the effects of zinc and/or multi-micronutrients on morbidity (n=612; height-for-age z-score <-1.5 SD). Outcomes measures were episodes of diarrhea (any reported, or with ≥3 stools in the last 24 h) and fever without localizing signs, as detected with health-facility based surveillance. Giardia was detected in stool by enzyme-linked immunosorbent assay. Among children who did not receive multi-nutrients, asymptomatic Giardia infection at baseline was associated with a substantial reduction in the rate of diarrhea (HR 0.32; 0.15-0.66) and fever without localizing signs (HR 0.56; 0.36-0.87), whereas no such effect was observed among children who received multi-nutrients (p-values for interaction 0.03 for both outcomes). This interaction was independent of age, HAZ-scores and distance to the research dispensary. There was no evidence that Giardia modified the intervention effect on nutritional status. CONCLUSION: Although causality of the Giardia-associated reduction in morbidity cannot be established, multi-nutrient supplementation results in a loss of this protection and thus seems to influence the proliferation or virulence of Giardia or associated intestinal pathogens.

Vitamin A supplementation modifies the association between mucosal innate and adaptive immune responses and resolution of enteric pathogen infections.

BACKGROUND: The efficacy of vitamin A supplementation on diarrheal disease morbidity may reflect the divergent effects that supplementation has on pathogen-specific immune responses and pathogen-specific outcomes. OBJECTIVE: We examined how vitamin A supplementation modified associations between gut-cytokine immune responses and the resolution of different diarrheal pathogen infections. DESIGN: Stools collected from 127 Mexican children who were 5-15 mo old and enrolled in a randomized, placebo-controlled vitamin A supplementation trial were screened for enteropathogenic Escherichia coli (EPEC), enterotoxigenic E. coli (ETEC), and Giardia lamblia. Fecal concentrations of interleukin (IL)-6, IL-8, IL-4, IL-5, IL-10, monocyte chemoattractant protein 1 (MCP-1), tumor necrosis factor-α (TNF-α), and interferon-γ (IFN-γ) were measured by using an enzyme-linked immunosorbent assay. Hazard models that incorporated categorized cytokine variables (ie, nondetectable, less than the median of detectable concentrations, and at least the median of detectable concentrations) were fit to the length of pathogen infections stratified by treatment group. RESULTS: Vitamin A-supplemented children with fecal MCP-1 or IL-8 concentrations less than the median of detectable concentrations and IL-10 concentrations of at least median concentrations had longer durations of EPEC infection than did children in the placebo group. In supplemented children, detectable fecal TNF-α or IL-6 concentrations were associated with shorter ETEC infection durations, whereas MCP-1 concentrations of at least the median were associated with longer infection durations. Children in this group who had IL-4, IL-5, or IFN-γ concentrations of at least median detectable concentrations had shorter durations of G. lamblia infection. CONCLUSION: The effect of supplementation on associations between fecal cytokine concentrations and pathogen infection resolution depends on the role of inflammatory immune responses in resolving specific pathogen infections.

Diagnóstico laboratorial da giardiose humana: comparação entre as técnicas de sedimentação espontânea em água e de centrífugo-flutuação em solução de sulfato de zinco / Laboratory diagnosis of human giardiasis: comparison between spontaneous sedimentation in water and zinc sulfate centrifugal flotation

Introdução: A giardiose é uma das enteroparasitoses mais prevalentes no nosso meio e acarreta morbidade de indivíduos e dispêndio de recursos pecuniários. O diagnóstico laboratorial da giardiose é essencial, sendo o exame parasitológico de amostras fecais por microscopia o padrão ouro, a despeito do surgimento de técnicas alternativas. Dada a possível diferença de sensibilidade empregando técnicas de concentração distintas, torna-se necessário uma comparação entre as mesmas. Objetivos: Os objetivos deste estudo foram comparar duas técnicas amplamente utilizadas para o diagnóstico da giardiose e, concomitantemente, caracterizar a população do estudo e avaliar a ocorrência de co-parasitoses. Métodos: As amostras foram coletadas no período de março a maio de 2010 (N =163), sendo provenientes de usuários do Laboratório de Análises Clínicas Prof. Rubens Dantas (LAC, Farmácia, UFRGS, Porto Alegre). As técnicas de concentração das amostras fecais empregadas para o diagnóstico foram a de sedimentação espontânea em água (HPJ) e a centrífugo- flutuação em solução de sulfato de zinco (Faust). Aplicou-se um questionário aos usuários do laboratório para melhor caracterização da população estudada. Resultados: A prevalência total de enteroparasitoses e de giardiose na população estudada foi, respectivamente, de 22,9% e de 10,7% empregando as duas técnicas de concentração. A giardiose foi mais pronunciada em crianças e idosos, principalmente, do gênero masculino. A técnica de Faust (N =11) apresentou maior sensibilidade quando comparada a técnica de HPJ (N =6). Conclusão: A técnica de Faust foi mais sensível para observação de cistos de Giardia lamblia podendo ser uma técnica complementar ao HPJ no diagnóstico deste protozoário.

Background: Giardiosis is one of the most prevalent enteric parasitic diseases in our environment and causes of morbidity and medical costs. The laboratory diagnosis of giardiosis is essential. The parasitological examination of fecal samples using microscopy is the gold standard method of diagnosis, despite of the emergence of alternative techniques. Different diagnostic methods must be compared because of the possible variation in sensitivity using different concentration techniques. Aim: The objectives of this study were to compare the two techniques widely used for diagnosis of giardiosis and, concomitantly, characterize the study population and evaluate the co-occurrence of parasitic diseases. Methods: The samples were collected between March and May 2010 (N =163) from Laboratório de Análises Clínicas Prof. Rubens Dantas (LAC, School of Pharmacy, UFRGS, Porto Alegre). The concentration techniques of fecal samples for diagnosis were spontaneous sedimentation in water (HPJ) and the zinc sulfate centrifugal-flotation (Faust). A questionnaire was completed by the users of the laboratory to better characterize the study population. Results: The prevalence of enteric parasitic diseases and giardiosis in the study population was, respectively, 22.9% and 10.7% using both techniques of concentration. Giardiosis was more pronounced in children and elderly, especially males. The Faust technique (N =11) showed higher sensitivity when compared to the HPJ technique (N =6). Conclusion: The Faust technique was more sensitive to the observation of Giardia lamblia and may be a complementary technique to HPJ.

Wheat germ supplement reduces cyst and trophozoite passage in people with giardiasis.

The protozoan parasite Giardia lamblia is a major cause of waterborne enteric disease worldwide. Lectins are proteins that bind to carbohydrate (sugar) moieties. Potential targets for lectins are found on the surface of most single-celled organisms. Modest concentrations of wheat germ agglutinin (WGA) have been shown to inhibit G. lamblia excystation and trophozoite growth in vitro and can reduce cyst passage in mice infected with the closely related protozoan parasite, G. muris. Commercial preparations of wheat germ (WG) contain 13-53 microg of WGA per gram. We performed a double-masked, placebo-controlled study of dietary supplementation with WG in 63 subjects with giardiasis in Montreal and Lima (25 asymptomatic patients passing cysts; 38 patients with symptoms). Asymptomatic subjects received WG (2 g, 3 times a day) or placebo (cornstarch, 2 g, 3 times a day) for 10 days, followed by metronidazole (250 mg 3 times a day) for 7 days. Symptomatic subjects received metronidazole (250 mg 3 times a day) plus either WG or placebo for 7 days. Stool specimens were collected every day (Montreal) or every other day (Lima) for 10 days and on Day 35 for microscopic examination and coproantigen determination. Subjects kept a diary of symptoms for 10 days after recruitment. In asymptomatic subjects, both cyst passage and coproantigen levels were reduced by approximately 50% in those taking WG compared with the placebo group (P < 0.01 and P = 0.06, respectively). In symptomatic subjects, cyst passage and coproantigen levels fell precipitously in response to metronidazole therapy, and there were no clinically important differences between those receiving supplemental WG or placebo. However, symptoms appear to have resolved more rapidly in the subjects taking WG in addition to metronidazole. The WG supplement was well tolerated in both symptomatic and asymptomatic subjects. These data suggest that components of WG, possibly WGA, either alone or in combination with antiprotozoal agents, can influence the course of human giardiasis.

Occurence of Cryptosporidium oocysts and Giardia cysts in water supplies of San Pedro Sula, Honduras

During June 1996, water supplies of the city of San Pedro Sula, Honduras, were sampled to obtain an assessment of Cryptosporidium oocyst and Guardia cyst concentrations. Each sample was concentrated and stained with an indirect immunofluorescent antibody, and parasites were counted through microscopic analysis. In three surface water supplies, Crytosporidium oocyst concentrations ranged from 58 to 260 oocysts per 100 L, and Giardia cysts were present in concentrations ranging 380 to 2100 cysts per 100 L. Unlike the surface water samples, groundwater acquifer protects the water supply more effectively from larger Giardia cysts. Cryptosporidium oocyst concentrations are within the typical range for surface water supplies in North America whereas Giardia cyst concentrations are elevated. Efforts should be made to protect raw water from sources of contamination (AU)

Proton-pump inhibition and gastric giardiasis: a causal or casual association?

Two patients who developed gastric giardiasis after 2 weeks of treatment with omeprazole 20 mg b.i.d. followed by omeprazole 20 mg per day for 2-6 weeks are described. In one patient, gastric giardiasis occurred in the presence of only mild intestinal metaplasia. In the other patient, Giardia lamblia infection had resolved 4 weeks after the cessation of omeprazole treatment, which, to our knowledge, is the first case reported in the literature. It is tempting to speculate that gastric giardiasis can develop in the absence of mucosal abnormalities during hypochlorhydria induced by treatment with a high dose of a proton-pump inhibitor. Specific treatment may not be required if the drug can be stopped and no other gastric disease causing hypochlorhydria is present.

Cloning of Thai strain Giardia intestinalis.

Axenic cultures of Giardia intestinalis trophozoites were successfully established from human fecal specimens and rectal swabs from dogs using sucrose gradient centrifugation to separate the cysts from fecal material, the excystation method of Robert-Thompson et al. and culture of the preparation in TYI-S-33 medium supplemented with human serum, vitamin mixture and piper acillin and amikacin antibiotics, respectively. Fungal contamination could be controlled by amphotericin B at 10 micrograms per ml of medium. Clones of the parasites were obtained using a combination of dilution method and micromanipulation technique.