Simultaneous increase of Cryptosporidium infections in the Netherlands, the United Kingdom and Germany in late summer season, 2012.

Starting August 2012, an increase in Cryptosporidium infections was reported in the Netherlands, the United Kingdom and Germany. It represented a 1.8 to 4.9-fold increase compared to previous years. Most samples were C. hominis IbA10G2. A case­control study was performed in the Netherlands but did not identify an endemic source. A case­case study in the north of England found travel abroad to be the most common risk factor.

WITHDRAWN: Drugs for treating giardiasis.

BACKGROUND: There can be a high rate of recurrence of disease after initial drug treatment for giardiasis. These drugs also have a range of adverse effects. OBJECTIVES: The objective of this review was to assess the effects of drug treatments for giardiasis. SEARCH STRATEGY: We searched the Cochrane Infectious Diseases Group Specialized Register, CENTRAL, MEDLINE, EMBASE, Current Contents, and reference lists of articles. SELECTION CRITERIA: Randomised and quasi-randomised trials of drug therapy for giardiasis compared with placebo or another drug. DATA COLLECTION AND ANALYSIS: Two reviewers independently assessed trial quality and extracted data. MAIN RESULTS: Thirty-four trials were included. Only one trial was without serious methodological flaws. Compared with placebo, drug treatment was associated with an improved cure rate (odds ratio 11.51, 95% confidence interval 2.29 to 57.98). Metronidazole treatment longer than three days had a better parasitological cure rate than other long treatment courses (odds ratio 2.41, 95% confidence interval 1.31 to 4.44), but there was significant heterogeneity between the trials. Available evidence has not detected a difference in cure between single dose therapy and longer treatment courses (odds ratio 0.33, 95% confidence interval 0.08 to 1.34). Within the single dose regimens, the available evidence did not demonstrate a difference in parasitological cure rate between tinidazole and other short therapies (odds ratio 3.39, 95% confidence interval 0.95 to 12.04), but had a higher clinical cure rate (odds ratio 5.33, 95% 2.66 to 10.67). AUTHORS' CONCLUSIONS: A single dose of tinidazole appears to give the highest clinical cure rate for giardiasis with relatively few adverse effects.

Genotyping of Giardia in Dutch patients and animals: a phylogenetic analysis of human and animal isolates.

Giardia duodenalis (syn. Giardia lamblia, Giardia intestinalis) is a protozoan organism that can infect the intestinal tract of many animal species including mammals. Genetic heterogeneity of G. duodenalis is well described but the zoonotic potential is still not clear. In this study, we analysed 100 Giardia DNA samples directly isolated from human stool specimens, to get more insight in the different G. duodenalis assemblages present in the Dutch human population. Results showed that these human isolates could be divided into two main Assemblages A and B within the G. duodenalis group on the basis of PCR assays specific for the Assemblages A and B and the DNA sequences of 18S ribosomal RNA and the glutamate dehydrogenase (gdh) genes. Genotyping results showed that G. duodenalis isolates originating from Dutch human patients belonged in 35% of the cases to Assemblage A (34/98) and in 65% of the cases to Assemblage B (64/98) whereas two human cases remained negative in all assays tested. In addition, we compared these human samples with animal samples from the Netherlands and human and animal samples from other countries. A phylogenetic analysis was carried out on the DNA sequences obtained from these Giardia and those available in GenBank. Using gdh DNA sequence analysis, human and animal Assemblage A and B Giardia isolates could be identified. However, phylogenetic analysis revealed different sub-clustering for human and animal isolates where host-species-specific assemblages (C, D, E, F and G) could be identified. The geographic origin of the human and animal samples was not a discriminating factor.

Triple Faeces Test: an effective tool for detection of intestinal parasites in routine clinical practice.

Microscopic examination of stool specimens is the cornerstone of detection of intestinal parasites in parasitology laboratories. In Europe, fresh, nonpreserved stool specimens are generally used for examination. Because intestinal parasites are shed intermittently, patients are asked to deliver multiple stool samples for examination. The limitation of this diagnostic approach is that detection of the vegetative stages of protozoa may be missed because of delays in processing and/or low compliance with the request to submit multiple stool samples. To overcome this limitation, a diagnostic test that combines multiple sampling (on 3 consecutive days), a fixative (SAF; sodium acetate acetic acid formalin), a concentration method and an easy-to-use permanent stain (chlorazol black dye) was developed for use in routine clinical practice. The results of the test, called the "Triple Faeces Test" (TFT), were compared with those of the conventional diagnostic method, i.e. ether sedimentation of a single fresh stool specimen. Stool samples from 544 patients were examined. Vials from the TFT-sets were filled by patients precisely according to instructions in 462 of 544 (85%) of the cases. Using the conventional method and the TFT, 106 and 209 patients, respectively, were diagnosed with infection by one or more parasitic species ( P<0.005). Pathogenic species were detected by the conventional method and by the TFT in 39 and 94 cases, respectively, and nonpathogenic species were detected in 124 and 288 cases, respectively ( P<0.05). Additional costs for the sampling device, laboratory reagents and handling of the TFT were acceptable. The results of this study suggest that the TFT is an effective method for detection of intestinal parasites in stool samples in routine clinical practice.

[Intestinal parasites in African asylum seekers: prevalence and risk factors]. / Darmparasieten bij Afrikaanse asielzoekers: prevalentie en risicofactoren.

OBJECTIVE: To determine the prevalence of potentially pathogenic intestinal parasites in asylum seekers coming from a highly endemic area, and to identify groups of asylum seekers from Africa with a high risk of an intestinal parasitic infestation which is potentially harmful of their own health or that of those in their vicinity. DESIGN: Prospective. METHOD: In the period January 1996-May 1999, 956 asylum seekers from Africa were checked for intestinal parasites by means of a stool examination within one month of arriving in the Netherlands. Independent variables for data analysis were sex, age and area of origin. RESULTS: Pathogenic intestinal parasites were found in 40.6% of the 956 African asylum seekers coming from areas south and east of the Sahara. Double-infection was found in 9.5% and triple-infection in 0.9% of the study population. The most common pathogenic parasite was Trichuris trichiura (13.6%) followed by Entamoeba histolytica/dispar (8.8%), hookworms (7.8%), Schistosoma (7.0%) and Giardia lamblia (5.0%). G. lamblia was the most commonly found potentially pathogenic parasite in children less than 13 years old (19.0%). In the population from Western Africa, 15.6% had a hookworm and 12.8% a Schistosoma. Both these helminthic infestations were three times as prevalent in men as in women. CONCLUSION: Sex, age and area of origin were important indicators for the species of parasite. On the basis of this, risk groups can be selected for screening for potentially pathogenic intestinal parasites.

Human giardiasis: genotype linked differences in clinical symptomatology.

Giardia duodenalis infection in humans can cause a variety of clinical symptoms. The relation between clinical symptomatology and the Giardia isolate genotype was studied in 18 Dutch patients infected with G. duodenalis who visited their general practitioner. Contrary to earlier studies, a 100% correlation between severity of diarrhoeal complaints and genotype was found: assemblage A isolates were solely detected in patients with intermittent diarrhoeal complaints, while assemblage B isolates were present in patients with persistent diarrhoeal complaints. These results are significant because they show for the first time that genetically linked features of G. duodenalis are major determinants in the severity of infection in human giardiasis.

Drugs for treating giardiasis.

BACKGROUND: There can be a high rate of recurrence of disease after initial drug treatment for giardiasis. These drugs also have a range of adverse effects. OBJECTIVES: The objective of this review was to assess the effects of drug treatments for giardiasis. SEARCH STRATEGY: We searched the Cochrane Infectious Diseases Group trials register, the Cochrane Controlled Trials Register, Medline and Embase, Current Contents, reference lists of articles. SELECTION CRITERIA: Randomised and quasi-randomised trials of drug therapy for giardiasis compared with placebo or another drug. DATA COLLECTION AND ANALYSIS: Two reviewers independently assessed trial quality and extracted data. MAIN RESULTS: Thirty-four trials were included. Only one trial was without serious methodological flaws. Compared with placebo, drug treatment was associated with an improved cure rate (odds ratio 11.5, 95% confidence interval 2.3 to 58). Metronidazole treatment longer than three days had a better parasitological cure rate than other long treatment courses (odds ratio 2.4, 95% confidence interval 1.3 to 4.4), but there was significant heterogeneity between the trials. Single dose therapy appeared equally effective as longer treatment courses (odds ratio 0.33, 95% confidence interval 0.08 to 1.34). Within the single dose regimens, tinidazole had a comparable parasitological cure rate to other short therapies (odds ratio 3.4, 95% confidence interval 0.95 to 12), but had a higher clinical cure rate (odds ratio 5.3, 95% 2.7-10.7). REVIEWER'S CONCLUSIONS: A single dose of tinidazole appears to give the highest clinical cure rate for giardiasis with relatively few adverse effects.

Sensitivity of microscopy versus enzyme immunoassay in the laboratory diagnosis of giardiasis.

The substitution of enzyme immunoassay (EIA) techniques for microscopy as a screening tool for Giardia lamblia infection was assessed. Paired stool samples obtained within a ten-day period from 366 patients with persistent diarrhea were examined by microscopy. In addition, two commercially available Giardia lamblia-specific EIAs were performed. Compared with microscopy, EIA for copro-antigen detection was more sensitive, based on examination of either one or two stool samples. Repeated examinations increased the number of cases detected, more so for microscopy than EIA. The negative predictive values of the two EIAs performed on the first stool sample were 98.7% and 97.8%. The results show that EIA for detection of copro-antigens in a single stool sample may be almost as sensitive for identifying Giardia infection as repeated microscopy on two sequential stool samples.

A systematic review on the treatment of giardiasis.

To assess the efficacy of treatment of parasitological excretion of cysts and trophozoites and symptoms of patients with giardiasis, a systematic review of published randomized clinical trials was conducted through extensive searches in Medline, Embase and Current Contents from 1966 till 1996 as well as manual reviews of 28 journals. The methodological quality of all trials was assessed by guidelines of the Cochrane Collaboration. Thirty-one trials were included, only one of which had no serious methodological flaws. The mean score of parasitological examination was 4.8 out of a possible 15. There was a considerable effect in cure rate of treatment versus placebo (odds 9.3, 95% CI 4.69-18.4), but all 3 trials in this comparison had serious flaws. Metronidazole treatment over more than 3 days seems to achieve a better parasitological cure rate than other long treatment courses (pooled odds 2.6, 95% 1.7-3.8), but trials are clinically and statistically heterogeneous. Single-dose therapy is as effective as longer treatment courses (pooled odds 0.67, 95% 0.31-1.44). Within the single-dose regimens tinidazole (2 g) reaches a higher parasitological cure rate than other short therapies (pooled odds 55, 95% CI 3.7-8.3) with relatively few side-effects. Placebo-controlled trials with parasitological and clinical outcomes are needed.

An outbreak of cryptosporidiosis in the Netherlands.

A hospital microbiologist in Spijkenisse, in the south west of the Netherlands - who had recently attended a parasitology course - identified cryptosporidial oocysts in stools from a patient with diarrhoea on 16 August 1995. Re-examination of 89 stool spe

Comparison of fresh versus sodium acetate acetic acid formalin preserved stool specimens for diagnosis of intestinal protozoal infections.

The use of sodium acetate acetic acid formalin (SAF)-preserved stool specimens was compared with that of nonpreserved specimens for the recovery of intestinal protozoa. A total of 247 patients, 170 with diarrhea of more than one week's duration and 77 refugees, were asked to collect a stool specimen. Each specimen was placed into two vials, one empty, the other containing SAF fixative. Laboratory investigations included microscopic examination of the concentrated sediment and direct wet smears from both types of stool specimens and the microscopic examination of a permanent stained smear from the unsedimented, SAF-preserved stool specimens. Examination of SAF-preserved stool specimens revealed intestinal protozoa in 149 of the 247 patients. With the conventional procedure using unpreserved stool specimens, intestinal protozoa were found in 89 of the 247 patients. The results show that the examination of SAF-preserved stool specimens, consisting of the microscopic examination of both the concentrated sediment and the permanent stained smear from the unsedimented material, increases the chance of recovering intestinal protozoa as compared to the conventional procedure.

[Underestimation of intestinal protozoa as a cause of diarrhea in family practice]. / Onderschatting van darmprotozoa als oorzaak van diarree in de huisartspraktijk.

OBJECTIVE: To assess the frequency of intestinal protozoa in stool samples of patients with diarrhoea in general practice. SETTING: General practitioners' laboratory in Haarlem, Netherlands. DESIGN: Descriptive study. METHOD: During one year (1 February 1992 to 31 January 1993) all stool samples from patients with diarrhoea visiting a general practitioner were examined according to a standard protocol consisting of bacterial and protozoal examination. RESULTS: Among 1703 stool examinations requested by general practitioners and performed according to the protocol, pathogenic protozoa were found in 10.8% and pathogenic bacteria in 8.6%. Of the 184 patients who tested positive for pathogenic protozoa 156 harboured Giardia lamblia, 22 Entamoeba histolytica and 6 Cryptosporidium spp. Pathogenic protozoa were predominantly found in patients with diarrhoea persisting for longer than 1 week and in cases with intermittent diarrhoea. In patients with acute diarrhoea (duration < 1 week) we predominantly found pathogenic bacteria (Campylobacyter jejuni). If the search for protozoa in the stool samples would not have been performed routinely, 34% of the pathogenic protozoa (Giardia lamblia) would not have been found. CONCLUSION: Intestinal infections with protozoa are not rare in general practice. It seems worthwhile to perform protozoal examination of the stool samples in case of persistent diarrhoea.