Comparative evaluation of real-time PCR and ELISA for the detection of human fascioliasis

Fascioliasis is a zoonotic parasitic infection caused by Fasciola species in humans and animals. Despite significant advances in vaccination and new therapeutic agents, little attention has been paid to validating methods for the diagnosis of fascioliasis in humans. Serological techniques are convenient assays that significantly improves the diagnosis of Fasciola infection. However, a more sensitive method is required. The aim of this study was to compare the Real-Time PCR technique with the indirect-ELISA for the detection of Fasciola hepatica in human. Using a panel of sera from patients infected with Fasciola hepatica (n = 51), other parasitic infections (n = 7), and uninfected controls (n = 12), we optimized an ELISA which employs an excretory-secretory antigens from F. hepatica for the detection of human fascioliasis. After DNA extraction from the samples, molecular analysis was done using Real-Time PCR technique based on the Fasciola ribosomal ITS1 sequence. Of 70 patient serum samples, 44 (62.86%) samples were identified as positive F. hepatica infection using ELISA and Real-Time PCR assays. There was no cross-reaction with other parasitic diseases such as toxoplasmosis, leishmaniasis, taeniasis, hydatidosis, trichinosis, toxocariasis, and strongyloidiasis. The significant difference between the agreement and similarity of the results of patients with indirect ELISA and Real-Time PCR was 94.4% and 99.2%, respectively (Cohen's kappa ≥ 0.7; P = 0.02). Based on the Kappa agreement findings, the significant agreement between the results of ELISA and Real-Time PCR indicates the accuracy and reliability of these tests in the diagnosis of F. hepatica in humans.

The Larval Stages of Echinostoma spp. in Freshwater Snails as the First and Second Intermediate Hosts in Gilan and Mazandaran Provinces, Northern Iran

Background

Identification of the larval stages of Echinostoma spp. in freshwater snails is an essential guide to continue monitoring the possibility of their transmission and the potential of echinostomiasis in areas where trematodes are the primary agent of parasitic diseases. The aim of this study was investigate Echinostoma using morphological and molecular techniques.

Methods

The study was conducted in Gilan and Mazandaran Provinces, northern Iran, from April 2019 to October 2021. Overall, 5300 freshwater snails were randomly collected and were identified using external shell morphology. Meanwhile, snails infected with trematodes were studied via shedding and dissecting methods. Larvae stages of Echinostoma were identified and the genomic DNA of the samples was extracted. The PCR amplification of the ITSI gene was carried out for 17 isolates and products were sequenced. Seven sequences were deposited in GenBank.

Results

Totally, 3.5% of snails containing three species (Stagnicola sp., Radix sp. and Planorbis sp.) were infected with two types of cercaria, E. revolutum with 37 and Echinostoma sp. with 45 spines in the collar. Moreover, 35% of the snails were infected with Echinostoma spp. metacercaria. Phylogenetic analysis illustrated that isolates were included in two ITSI haplogroups.

Conclusion

Results showed the potential hazard of a zoonotic parasite as Echinostoma in northern Iran. The potential of disease environmental relationship investigation and resource control optimization is necessary for effective disease prevention and health management.

Molecular Characterization of Animal Fasciola Spp. Isolates from Lorestan Province, Western Iran

BACKGROUND

We aimed to detect the genetic diversity of samples identified morphologically as Fasciola spp. from sheep, cattle and goat from Lorestan Province, western Iran using PCR-RFLP method. Besides, we evaluated the genetic diversity indices, sequencing and phylogenetic analysis using mitochondrial gene (ND1 and CO1).

METHODS

PCR-RFLP analysis of ribosomal ITS1 fragment by RsaI restriction enzyme to investigate the genetic characteristics of Fasciola species obtained from different hosts (18 sheep, 21 cattle, and 17goats) was conducted. The samples were sequenced. Sequences were evaluated using BLAST software and the parasite species were identified with similarity percentage and overlap with the species registered in the gene bank. Then similarity and diversity of intra-species and intra-species diversity of Fasciola species were calculated.

RESULTS

In Lorestan, based on RFLP pattern, 93% (52) of the Fasciola spp. isolates had a RFLP pattern related to F. hepatica and 7% (4) were F. gigantica. No hybrid forms were detected. The CO1 gene could clarify 19 haplotypes against ND1 gene that found 22 haplotypes among livestock. Sequencing results of the mtDNA showed intra-species identity 98. 5%-100% and Intra-species-diversity: 0-1.5% compared to the GenBank sequences.

CONCLUSION

Using PCR-RFLP method, two species of F. hepatica and F. gigantica, were present in Lorestan Province, but F. hepatica was more prevalent. Mitochondrial genes could better test variability indices in different hosts than ribosomal genes, consequently among mitochondrial genes, the ND1 gene could better examine differences and similarities than CO1.

Risk Mapping and Spatial Modeling of Human Cystic Echinococcosis in Iran from 2009 to 2018: A GIS-Based Survey

BACKGROUND

Cystic echinococcosis (CE) is one of the most important parasitic infections in subgroup seven common neglected diseases of humans and animals. It is in the list of 18 neglected tropical diseases of the WHO. We aimed to analyze the situation of the disease in Iran using Geographical Information System (GIS) and satellite data analysis.

METHODS

The data obtained from the Ministry of Health and Medical Education, Tehran, Iran and other related centers from 2009 to 2018 were analyzed using GIS. Then, the spatial distribution maps of the disease were generated, and the hot spots of the disease in Iran were determined using spatial analysis of ArcGIS10.5 software. Geographically weighted regression (GWR) analysis in ArcGIS10.5 was used to correlate the variables affecting the disease including temperature, relative humidity, normalized different vegetation index (NDVI) and incidence of hydatidosis. Data analysis was performed by Linear regression analysis and SPSS 21 software using descriptive statistics and chi-square test.

RESULTS

Zanjan, Khorasan Razavi, North Khorasan, Chaharmahal Bakhtiari, Hamedan, Semnan, and Ardabil provinces were the hot spots of CE. The results of geographical weighted regression analysis showed that in Khorasan Razavi, North Khorasan, Chaharmahal Bakhtiari, Hamedan, Semnan, Ardabil, Zanjan, Qazvin, and Ilam provinces, the highest correlation between temperature, humidity, vegetation density and the incidence of hydatidosis was observed (P<0.001).

CONCLUSION

The use of maps could provide reliable estimates of at-risk populations. Climatic factors of temperature, humidity, NDVI had a greater impact on the probability of hydatidosis. These factors can be an indicator used to predict the presence of disease. Environmental and climatic factors were associated with echinococcosis.

Contamination of Vector Snails with the Larval Stages of Trematodes in Selected Areas in Northern Iran

BACKGROUND

Identification of freshwater snails and possible trematodes transmission sites are essential to continue monitoring the potential for disease outbreaks in areas with a history of parasitic infections. We aimed to search some areas in the margin of the Caspian Sea, northern Iran to identify the snail fauna of this area and verify the contamination of vector snails.

METHODS

More than 5,308 snails from 51 diverse and permanent habitats were studied from April 2019 to October 2021. Snails were collected randomly and identified using shell morphology. Trematode infection in snails was investigated by the release of cercariae and dissection methods.

RESULTS

Five families of freshwater snails including Lymnaeidae, Physidae, Planorbidae, Bithyniidae, and Viviparidae were investigated in the Caspian Sae Litoral of Iran. Physidae were found as the most prevalent snails (55.1%) followed by Lymnaeidae (29.4%). The parasitize rate was observed as 20% using releasing cercaria technique. Echinostomatoidea (31%), Schistosomatoidea (8%), and Diplostomoidea (21%), and Plagiorchioidea (40%) were seen as detected parasites. Meanwhile, 60% of the studied snails illustrated the other stages of trematodes.

CONCLUSION

The rate of infection of snails with different cercaria in northern Iran is significant. It needs further deep studies to clarify the situation of zoonoses transmitted by snails in the region. Policy makers should pay attention more to this area in terms of monitoring the snail-transmitted diseases.

Changes in the expression of miR-103a and miR-21: a functional diagnosis of toxocariasis in rats

Introduction. Toxocariasis is a zoonotic parasitic disease caused by migrating nematode worms, Toxocara species larvae, within tissues. MicroRNAs (miRNAs) are small RNA molecules that regulate gene expression at a post-transcriptional level.Hypothesis/Gap Statement. miRNA-based diagnostic biomarkers for toxocariasis are emerging, but there is limited information about the role of many miRNAs and a more detailed diagnostic evaluation of miRNA expression patterns is needed to understand their immunobiological function.Aim. We investigated the expression levels of circulating miRNA 21 and miRNA 103a as potential biomarkers for the prediction and diagnosis of toxocariasis in Wistar rats infected with Toxocara canis.Methodology. Thirty Wistar rats were inoculated orally with 2500 T. canis embryonated eggs via gavage. Serum samples were collected from infected animals and were tested against T. canis antigens for 60 days post-infection. The plasma samples were isolated for quantitative real-time PCR (qPCR) assays and qPCR was used to assess transcription levels of miRNA 21 and miRNA 103a.Results. The prevalence of anti-Toxocara IgG was detected in 7/30 (23.3 %) infected rats. Molecular analysis of miRNAs 21 and 103a showed that expression levels of miRNAs in both groups of Toxocara-positive and negative samples were the same without significant association. The ratio of housekeeping gene expression (U6) to gene expression of miRNAs 21 and 103a indicated the rate of change (1/1.38 ≈ 0.75 and 1/0.751 ≈ 1.3, respectively).Conclusion. Our study revealed that miRNAs 21 and 103a might play fundamental roles as biomarkers and diagnostic tools for toxocariasis. However, the changes in expression of these miRNAs were not adequate to be used as biomarkers in diagnosis.

A Retrospective Study of Serum Calcium Status in Tehran, Iran (105,128 Samples, from 2009-2018)

Background: Calcium is a necessary mineral for life to keep the body and bones healthy. Various factors including hormones, diet, age, and gender affect serum calcium status. The aim of this sturdy was to assess the serum calcium level (SCL) of Tehran population, which has about 10 million multi-Ethnic populations and represents from the whole country. Methods: In this retrospective study, the measured SCL of 105,128 individuals referred to different laboratories of Tehran, Iran were evaluated and its relationship with the age, gender, seasons, and different years during 2009-2018, were analyzed. Results: After excluding outliers, 91,257samples remained, which 61162 (58.64%) and 30,095 (41.36%) were female and male, respectively.  The mean SCL was 9.36 (9.35, 9.37) mg/dl (95%CI). The highest and lowest SCLs were 3.1 and 18.2mg/dl, respectively. From the total study population, 74127 (81.23%) had normal SCLs, 14110 (15.46%) had hypocalcemia, and 3020 (3.31%) had hypercalcemia. SCLs were normal in 83.6% of men and 79.66% of women. Women had a significantly higher frequency of hypocalcemia compared to men (17.2% vs. 12.83%, p<0.0001). Conclusion: Normal and abnormal SCLs were significantly different in age groups and in both genders. It means that gender and age affect SCLs. Every year of increasing age, reduces the chance of hypercalcemia by 40%, significantly. Age seems to affect hypercalcemia more than hypocalcemia. Age in men increases the risk of hypocalcemia, and reduces the risk of hypocalcemia in women. Therefore, it is recommended to encourage dietary calcium intake among premenopausal women and older men.

Evaluation of Semi-Nested PCR Compared with Indirect-ELISA to Diagnose Human Fasciolosis

Background: We aimed to compare semi-nested PCR with indirect ELISA to diagnose human fasciolosis. Methods: Overall, 70 serum samples were collected from different areas in Iran suspected for fascioliasis. Individuals were classified based on diagnostic of fascioliasis and habitat in endemic areas. Finally, all serum samples were tested by indirect ELISA (using secretory excretory antigen) and semi-nested PCR (using ITS1 gene). The study was conducted in the School of Publish Health, Tehran University of Medical Sciences, Iran in 2021. Results: Significant differences were found between agreement and similarity of patients' results of indirect ELISA and semi-nested PCR 94.46% and 98.4% respectively (Cohen's kappa ≥0.6; P-value≤0.05). No cross-reactions were observed with other parasitic diseases (toxocariasis, hydatidosis, strongyloidiasis, toxoplasmosis, cutaneous leishmaniasis, taeniasis and trichinosis). 69.84% of samples were positive by both techniques. In addition, the percentage of agreement and similarity between the results of the two techniques based on habitat in endemic areas was 88.9-100% and 97.7-100%, respectively (Cohen's kappa ≥0.6; P-value≤0.05). Conclusion: Semi-nested PCR could be a suitable method for following up on patients' treatment and a confirmatory method for ELISA as for diagnosis of human fascioliasis.

Estimation of Burden of Cystic Echinococcosis in Iran Using Disability Adjusted Life Years (DALYs) in 2018

Background:

Human hydatidosis as a public concern has increased in a number of countries that have reduced control programs for the disease due to lack of resources or policies. We aimed to estimate Disability-Adjusted Life Years (DALYs) for human hydatidosis in Iran in 2018.

Methods:

Data were collected from the Center of Communicable Diseases Control, Ministry of Health &Medical Education, Tehran, Iran in 2018. To calculate DALYs, years of life lost due to premature death (YLL) with years of life with disability (YLD) were calculated according to the formula as DALY = YLL + YLD. The standard life expectancy lost method (SEYLL) was used to calculate the years lost due to premature death.

Results:

DALYs for human hydatidosis was calculated as 1210.12 years (YLD equals to 177.12 and YLL equals to 1033) in Iran for the year 2018. It was estimated to be 700.2 years for men and 509.8 years for women. DALYs in men were significantly different from women (P= 0.001) so DALYs were more in men than women were. YLD was calculated at 78.228 years in men and 98.892 years in women and in both men and women at 177.12 years. YLD was significantly different in women compared to men (P=0.001), so YLD in women was more than in men.

Conclusion:

We reached considerable indices for hydatidosis in our study. Therefore, disease prevention and control programs in Iran seem necessary by the policy makers.

Serological Detection of Trichinellosis among Suspected Wild Boar Meat Consumers in North and Northeast of Iran

Background

Trichinellosis is a foodborne zoonosis disease worldwide. Humans acquire infection by ingesting raw or uncooked animal flesh containing viable Trichinella larvae. The most common reservoirs of this helminth are pigs and wild boars. In northern Iran, hunting and consuming wild boars meat by some communities, including ethnic Armenians, may expose them to trichinellosis. Here, we investigated anti-Trichinella IgG antibodies in high-risk individuals in northeastern Iran.

Methods

From Mar to Aug 2020, we collected 189 blood samples from individuals with a history of wild boar meat consumption and examined the sera for anti-Trichinella IgG antibodies using a commercial ELISA kit (NovaTec Immunodiagnostica GmbH, Germany). Sera from 30 individuals with no history of eating wild boar meat was used to determine the range of actual negative values and possible cross-reactivity with other similar antigens.

Results

Of the 189 participants, 5 (2.6%) had anti-Trichinella IgG antibodies (OD, 1.176 ±0.154). None of the 30 negative controls became positive (OD, 0.198 ± 0.044). The age, gender, occupation, and education showed no significant association with Trichinella seropositivity rate (P>0.05). All five seropositive cases were among 112 individuals (4.46% seropositivity) that resided in the western part of the study area, stretching from Behshar to Gorgan.

Conclusion

Eating wild boar meat might expose individuals to trichinellosis in the north and northeast of Iran. Further studies with more individuals from different parts of the country and confirmation of the ELISA by additional tests like Western blot will give a more in-depth insight into human trichinellosis epidemiology in Iran.

Lymphatic filariasis in Asia: a systematic review and meta-analysis

Lymphatic filariasis (LF) is an important neglected parasitic disease according to the World Health Organization. In this study, we aimed to determine the prevalence of human LF in Asia using a systematic review and meta-analysis approach. Records from 1990 to 2018 in reputable databases including PubMed, Science Direct, Embase, and Cochrane Library were searched using a panel of related keywords. All 48 countries of Asia were searched one by one in combination with the keywords. In all, 41,742 cases identified in this study were included in the analysis. According to our findings, the pooled prevalence of LF in Asia was estimated at 3% (95% CI: [1.7, 5.2]). There was no major trend in the cumulative prevalence of LF over time. Some countries in Asia including China, Japan, Vietnam, and South Korea succeeded in eliminating LF as a public health problem, but others still need to monitor the disease. Based on the initiative of the WHO starting in 2000, some countries in Asia succeeded in eliminating LF as a public health problem. Other countries have taken steps to eliminate the disease with variable degrees of success. These efforts might be affected by issues such as climate change.

Emerging Cases of Fascioliasis in Lorestan Province, Western Iran: Case Series Report

Fascioliasis is a zoonotic disease caused by Fasciola spp. We report five serologically and molecularly confirmed cases in an emerging region in Iran. A retrospective, case series study, performed in Lorestan Province, west of Iran between January 2015 and June 2016. From 1256 patients examined, 16 patients had positive serum ELISA. Five cases were approved as infected with fasciolosis using stool exam and PCR. Age ranged from 24 to 80 yr with mean age of 45 years. All of patients were adults and four of them had abdominal and back pain. Other symptoms included fever and chills, coughing and sore throat, weight loss, cutaneous manifestations. All patients lived in the rural environment, and four reported the ingestion of raw aquatic plants such as watercress. In fecal examination for fluke eggs, four samples were positive for F. hepatica eggs. Conventional PCR analysis showed that five human stools were positive for F. hepatica. All of 5 patients were treated with the usual dose of triclabendazole. A history of recent consumption of raw aquatic plants (in 4 out of 5 patients) is an important finding, but in one patient the source of infection remained unclear. Lorestan should be considered as an emerging region for this disease and further research in this province should be carried out.

A faunistic survey of snails and their infection with digenean trematode cercariae in Bandar-e Anzali at the littoral of the Caspian Sea

Trematodes are known as a diverse group of endogenous parasites, which snails as their intermediate hosts can dramatically affect parasite transmission dynamics. Snails play a key role in life cycles of digenean trematode. However, there has not been much faunistic surveys in terms of snails' distribution in Iran. The current study was aimed to identify snail's fauna and their current geographic distribution in four regions of Guilan province, Iran. Several species of snails (land and freshwater snails) were obtained from 4 different areas (2018-2019), and then samples were separately transferred to the laboratory. Diagnosis of snails was then performed according to morphometric characteristics including dextral or sinistral shell, shape, color and size of shell. Moreover, radula was stained and then photographed under microscopic examination. Furthermore, 25% of any species were tested for cercarial infection. In total, 2082 snails belonging to 12 species were identified based on the morphological characteristics. Land snails were identified to be Helicella sp. (46.4%), Helix aspersa (34.1%), Helicopsis sp. (8%), Pomatia sp. (6.7%) and Oxyloma elegans (4.8%). Moreover, freshwater snails were Physa acuta (30.6%), Lymnaea auricularia (25.8%), Lymnaea gedrosiana (18.7%), Lymnaea palustris (8.9%), Lymnaea truncatula (8.1%), Planorbis sp. (6.4%) and Lymnaea stagnalis (1.5%). In collected snails, Lymnaea auricularia (0.66%) and Lymnaea gedrosiana (0.45%) were the only snails harboring cercariae (Gymnocephalus cercariae). There was no statistically significant difference between the cercarial infection and snail species (P<0.05). Comprehensive field studies are highly needed for better evaluation of the snail biodiversity in the Caspian Sea region due to the particular climatic conditions and the high prevalence of trematodosis.

Expression of Mir-21 and Mir-103a in Toxocara canis: Potential for Diagnosis of Human Toxocariasis

Background:

Toxocariasis is one of the most neglected zoonotic diseases, predominantly caused by Toxocara canis. We aimed to evaluate the expression of microRNAs 21 and 103a in seropositive individuals for human toxocariasis as diagnostic biomarkers.

Methods:

This study was conducted on 324 individuals for ELISA test on toxocariasis in Tehran and Karaj, Iran 2019. Then positive samples for anti-Toxocara IgG were obtained to quantitative Real-time PCR (qRT-PCR) assays to investigate the transcriptional profiles of miRNAs predicted to be involved in developmental and reproductive processes. qPCR was employed to assess levels of transcription for miRNAs of 103a and 21 in plasma samples.

Results:

After the experiments, the results were evaluated by REST software, Livak formula and quantitative t-test. The analyzes performed on human samples showed that in the case group compared to the control group, only in Tc-miR-21 gene, a 0.3-fold increase in expression was obtained with REST software (Fold change ≤ 1.5, P>0.05), which was statistically significant by t-test (P<0.05).

Conclusion:

To our knowledge, this is the first study to evaluate miR-21 and miR-103a in toxocariasis, which shed light on the fundamental role of it as a biomarker and diagnostic tool. However, due to the changes in expression of these miRNAs were not vast to be used as biomarkers in diagnosis. Despite of that the changes in the expression of these miRNAs were not vast but they could serve as novel promising biomarkers for diagnosis of toxocariasis.

Human Cysticercosis in Asia: A Systematic Review and Meta-Analysis

Background:

Cysticercosis in among the neglected tropical disease caused by eating the egg of parasite Taenia solium. In this review, we aimed to verify the prevalence of human cysticercosis in different countries of Asia using systematic review and meta-analysis approach.

Methods:

Based of the protocol, reliable databases including PubMed, SCOPUS, Science Direct, Embase, and Cochrane Library from 1990–2018 were searched using a panel of keywords. Overall, 48 countries of Asia were searched in turn and data were analyzed using a category of statistical tests.

Results:

Out of 28 included studies, 586175 samples were collected and included in the data analysis. Based on the meta-analysis results, the overall pooled percent of cysticercosis was estimated 3.8% (95% CI: [2.0, 7.0]). According to the result of heterogeneity statistics including I-squared, chi-square, and tau-squared, it was statistically significant (Tau2 = 2.94, chi2 = 12733.31, P<0.001, I2 = 100%) therefore a random effect model was used to handle the heterogeneity of studies. To evaluate the trend of cysticercosis over the time, Cumulative meta-analysis was performed and the result showed that there was a minor upward tendency in the prevalence of cysticercosis over the time.

Conclusion:

Although, considering the religious culture and food habits in Asia, we might have expected to witness a low prevalence of human cysticercosis, but we noticed more or less significant infection in some countries of the region. Regarding the new feature of immigration and travel between countries, all authorities are advised to take measures on controlling and monitoring the disease.

Molecular phylogenetic and genetic variability of Fasciola gigantica in Kermanshah province, western Iran with an overview to understand haplotypes distribution in Asia and Africa

Over the last decade, diagnostic tools to detect and differentiate Fasciola species have improved, but our understanding of the distribution of haplotypes and population structure of this parasite is less clear. This study was designed to survey this gap in the F. gigantica epidemiology in Kermanshah province, western Iran from 2015 to 2017. Sixty-eight Fasciola isolates were collected from slaughterhouses from this province. We evaluated the PCR-RFLP assay of the ITS1 genes for the identification of Fasciola species using the RsaI enzyme. After Fasciola species identification, the partial sequence of mitochondrial NADH dehydrogenase subunit 1 (ND1) gene of F. gigantica was used for subsequent construction of the phylogenetic tree and network analysis. Based on the PCR-PRFLP profile, one (6.25%) of sheep isolates and 19 (39.60%) of cattle isolates were detected as F. gigantica, whereas 93.75% of sheep isolates, 60.40% of cattle isolates and all of the goat isolates were F. hepatica. In the 20 analyzed flukes, five ND1 haplotypes were detected. Statistically significant genetic differentiation was demonstrated between the Iran population and all the other populations. Evidence is presented for the existence of two well-separated populations: African and West Asian gigantica flukes and East Asian gigantica flukes. Genetic relationships among haplotypes were associated with geographical divisions. Also, our results have heightened our knowledge about the genetic diversity of F. gigantic, providing the first evidence for the existence of two well-separated populations of this parasite.

Seroprevalence of Toxocara Infection in Association with Different Risk Factors among Children of 4-12 Years Old Referred to Some Medical Centers in Aras Free Zone, Northwest Iran

Background:

Toxocariosis is a parasitic disease caused by the larval stage of Toxocara species from dog and cat. It has a worldwide distribution with higher prevalence in children. This study aimed to determine seroprevalence of Toxocara infection and its association with some risk factors among children of Aras Free Zone (Jolfa City) in Northwest of Iran.

Methods:

Sera were collected from 514 children aged 4–12 yr old attending to some medical centers in the study area from May 2018 to Feb 2019. Anti-Toxocara IgG antibodies assay was performed using commercial ELISA kit (Nova Tec, Germany). The seropositivity rate was determined and its association with different demographic criteria and risk factors were statistically analyzed.

Results:

The overall seroprevalence was 2.3% (12/514). Risk factors of children’s age group and contact with either pet animals (dog and cat) and/or soil were significantly associated with seropositivity. However, there was not any relationship between Toxocara infection and gender of children, place of residency (urban or rural) and their mothers’ education level.

Conclusion:

Both girls and boys are at risk of Toxocara infection in the study area. Younger age of childhood and contact with sources of infection were important associated factors. More probably, additional criteria are involved in the initiation of infection.

Comprehensive Survey of Plagiarism in Iran

Background and Objective:

We conducted this study to assess the prevalence of plagiarism and to shed light on some dark aspects of this issue. The main objectives included to find out the etiology, prevalence, and detection of various forms plagiarism.

Methods:

In this Cross-sectional study we used a questionnaire, face-to-face interview, analyzing the present notifications and codes, websites, and literature review. The current study was conducted throughout Iran from 2017-2018. Those associated with scientific journalism, academic staffs, and authors were interviewed or asked to fill out a prepared questionnaire.

Results:

Nine hundred seventy nine questionnaires were circulated. Out of this 706 (72.1%) were completed and returned. Those with a master degree were most cooperative in filling out the questionnaires (36.4%); followed by Assistant Professors (29.6%). About 74.1% of respondents, had not participated in any educational workshops on plagiarism (P<0.001) while 10.8% had not heard anything about plagiarism (P<0.001). As regards correct reply as for definition and detecting plagiarism; 91.1%, 40.8%, 48.4% and 57.9% could reply correctly (P<0.001). Forty-one-point one percent of the participants believed that reprimand would be the best punishment. The percentage of plagiarism as per people associated in journal administration, was 22.9%; based on experts’ opinions, it was 30.0%; and based on analysis of some journals published in Iran, it was 25.5%.

Conclusion:

We found a noticeable prevalence of plagiarism in Iran. Many factors are involved in this misconduct; most important being the need for academic staff and students to publish e more papers regardless of their quality to meet some of the academic requirements. Considering the high rank of Iran in terms of scientific growth worldwide, it is expected from the regulatory authorities to monitor all aspects of scientific misconducts in medical journalism.

Seroepidemiology of human fascioliasis in rural and nomad areas of Lorestan Province, western Iran, in 2016 and 2017

According to previous studies in Lorestan Province, western Iran on human fascioliasis, we aimed to understand the epidemiology of the disease and to identify the cases in rural and nomad regions of this province. The studied population was a rural and nomadic population of nine districts of Lorestan province, of which 1053 were selected according to the population of each studied county based on random sampling in 2016-2017. Initially, a questionnaire was completed for each person, including age, gender, education, occupation, use of local native aquatic plants and history of travel to the northern provinces of the country where fasciolosis has been reported mostly. Then, 5 ml blood samples were taken and the samples were evaluated as for anti-Fasciola specific antibodies using ELISA technique. Overall, 1053 individuals were participated, of which 28 (2.66%) were infected with fasciolosis and 18 positive cases were female. The highest infection rate was in the age group of 20-29 years (23%) followed by 30-39 years of age (22%). There was no significant difference between the rate of infection in terms of gender (P = 0.89), age (P = 0.15), travel history to the northern provinces of the country (P = 0.089), history of aquatic plant consumption called Balmak natively (P = 0.48), history of surface water consumption (springs, streams) (P = 0.18), and occupation (P = 0.43). Considering the results of current and previous studies it seems that the disease in the Lorestan province is expanding and new foci in different parts of the province are formed or are being formed. Therefore, the preventive measures, control and treatment should be taken in areas with parasites transmission.

Molecular phylogenetic and genetic variability of Fasciola gigantica in Kermanshah province, western Iran with an overview to understand haplotypes distribution in Asia and Africa

Over the last decade, diagnostic tools to detect and differentiate Fasciola species have improved, but our understanding of the distribution of haplotypes and population structure of this parasite is less clear. This study was designed to survey this gap in the F. gigantica epidemiology in Kermanshah province, western Iran from 2015 to 2017. Sixty-eight Fasciola isolates were collected from slaughterhouses from this province. We evaluated the PCR-RFLP assay of the ITS1 genes for the identification of Fasciola species using the RsaI enzyme. After Fasciola species identification, the partial sequence of mitochondrial NADH dehydrogenase subunit 1 (ND1) gene of F. gigantica was used for subsequent construction of the phylogenetic tree and network analysis. Based on the PCR-PRFLP profile, one (6.25%) of sheep isolates and 19 (39.60%) of cattle isolates were detected as F. gigantica, whereas 93.75% of sheep isolates, 60.40% of cattle isolates and all of the goat isolates were F. hepatica. In the 20 analyzed flukes, five ND1 haplotypes were detected. Statistically significant genetic differentiation was demonstrated between the Iran population and all the other populations. Evidence is presented for the existence of two well-separated populations: African and West Asian gigantica flukes and East Asian gigantica flukes. Genetic relationships among haplotypes were associated with geographical divisions. Also, our results have heightened our knowledge about the genetic diversity of F. gigantic, providing the first evidence for the existence of two well-separated populations of this parasite.

Global, regional, and national under-5 mortality, adult mortality, age-specific mortality, and life expectancy, 1970-2016: a systematic analysis for the Global Burden of Disease Study 2016

BACKGROUND

Detailed assessments of mortality patterns, particularly age-specific mortality, represent a crucial input that enables health systems to target interventions to specific populations. Understanding how all-cause mortality has changed with respect to development status can identify exemplars for best practice. To accomplish this, the Global Burden of Diseases, Injuries, and Risk Factors Study 2016 (GBD 2016) estimated age-specific and sex-specific all-cause mortality between 1970 and 2016 for 195 countries and territories and at the subnational level for the five countries with a population greater than 200 million in 2016.

METHODS

We have evaluated how well civil registration systems captured deaths using a set of demographic methods called death distribution methods for adults and from consideration of survey and census data for children younger than 5 years. We generated an overall assessment of completeness of registration of deaths by dividing registered deaths in each location-year by our estimate of all-age deaths generated from our overall estimation process. For 163 locations, including subnational units in countries with a population greater than 200 million with complete vital registration (VR) systems, our estimates were largely driven by the observed data, with corrections for small fluctuations in numbers and estimation for recent years where there were lags in data reporting (lags were variable by location, generally between 1 year and 6 years). For other locations, we took advantage of different data sources available to measure under-5 mortality rates (U5MR) using complete birth histories, summary birth histories, and incomplete VR with adjustments; we measured adult mortality rate (the probability of death in individuals aged 15-60 years) using adjusted incomplete VR, sibling histories, and household death recall. We used the U5MR and adult mortality rate, together with crude death rate due to HIV in the GBD model life table system, to estimate age-specific and sex-specific death rates for each location-year. Using various international databases, we identified fatal discontinuities, which we defined as increases in the death rate of more than one death per million, resulting from conflict and terrorism, natural disasters, major transport or technological accidents, and a subset of epidemic infectious diseases; these were added to estimates in the relevant years. In 47 countries with an identified peak adult prevalence for HIV/AIDS of more than 0·5% and where VR systems were less than 65% complete, we informed our estimates of age-sex-specific mortality using the Estimation and Projection Package (EPP)-Spectrum model fitted to national HIV/AIDS prevalence surveys and antenatal clinic serosurveillance systems. We estimated stillbirths, early neonatal, late neonatal, and childhood mortality using both survey and VR data in spatiotemporal Gaussian process regression models. We estimated abridged life tables for all location-years using age-specific death rates. We grouped locations into development quintiles based on the Socio-demographic Index (SDI) and analysed mortality trends by quintile. Using spline regression, we estimated the expected mortality rate for each age-sex group as a function of SDI. We identified countries with higher life expectancy than expected by comparing observed life expectancy to anticipated life expectancy on the basis of development status alone.

FINDINGS

Completeness in the registration of deaths increased from 28% in 1970 to a peak of 45% in 2013; completeness was lower after 2013 because of lags in reporting. Total deaths in children younger than 5 years decreased from 1970 to 2016, and slower decreases occurred at ages 5-24 years. By contrast, numbers of adult deaths increased in each 5-year age bracket above the age of 25 years. The distribution of annualised rates of change in age-specific mortality rate differed over the period 2000 to 2016 compared with earlier decades: increasing annualised rates of change were less frequent, although rising annualised rates of change still occurred in some locations, particularly for adolescent and younger adult age groups. Rates of stillbirths and under-5 mortality both decreased globally from 1970. Evidence for global convergence of death rates was mixed; although the absolute difference between age-standardised death rates narrowed between countries at the lowest and highest levels of SDI, the ratio of these death rates-a measure of relative inequality-increased slightly. There was a strong shift between 1970 and 2016 toward higher life expectancy, most noticeably at higher levels of SDI. Among countries with populations greater than 1 million in 2016, life expectancy at birth was highest for women in Japan, at 86·9 years (95% UI 86·7-87·2), and for men in Singapore, at 81·3 years (78·8-83·7) in 2016. Male life expectancy was generally lower than female life expectancy between 1970 and 2016, and the gap between male and female life expectancy increased with progression to higher levels of SDI. Some countries with exceptional health performance in 1990 in terms of the difference in observed to expected life expectancy at birth had slower progress on the same measure in 2016.

INTERPRETATION

Globally, mortality rates have decreased across all age groups over the past five decades, with the largest improvements occurring among children younger than 5 years. However, at the national level, considerable heterogeneity remains in terms of both level and rate of changes in age-specific mortality; increases in mortality for certain age groups occurred in some locations. We found evidence that the absolute gap between countries in age-specific death rates has declined, although the relative gap for some age-sex groups increased. Countries that now lead in terms of having higher observed life expectancy than that expected on the basis of development alone, or locations that have either increased this advantage or rapidly decreased the deficit from expected levels, could provide insight into the means to accelerate progress in nations where progress has stalled.

FUNDING

Bill & Melinda Gates Foundation, and the National Institute on Aging and the National Institute of Mental Health of the National Institutes of Health.

Global, regional, and national age-sex specific mortality for 264 causes of death, 1980-2016: a systematic analysis for the Global Burden of Disease Study 2016

BACKGROUND

Monitoring levels and trends in premature mortality is crucial to understanding how societies can address prominent sources of early death. The Global Burden of Disease 2016 Study (GBD 2016) provides a comprehensive assessment of cause-specific mortality for 264 causes in 195 locations from 1980 to 2016. This assessment includes evaluation of the expected epidemiological transition with changes in development and where local patterns deviate from these trends.

METHODS

We estimated cause-specific deaths and years of life lost (YLLs) by age, sex, geography, and year. YLLs were calculated from the sum of each death multiplied by the standard life expectancy at each age. We used the GBD cause of death database composed of: vital registration (VR) data corrected for under-registration and garbage coding; national and subnational verbal autopsy (VA) studies corrected for garbage coding; and other sources including surveys and surveillance systems for specific causes such as maternal mortality. To facilitate assessment of quality, we reported on the fraction of deaths assigned to GBD Level 1 or Level 2 causes that cannot be underlying causes of death (major garbage codes) by location and year. Based on completeness, garbage coding, cause list detail, and time periods covered, we provided an overall data quality rating for each location with scores ranging from 0 stars (worst) to 5 stars (best). We used robust statistical methods including the Cause of Death Ensemble model (CODEm) to generate estimates for each location, year, age, and sex. We assessed observed and expected levels and trends of cause-specific deaths in relation to the Socio-demographic Index (SDI), a summary indicator derived from measures of average income per capita, educational attainment, and total fertility, with locations grouped into quintiles by SDI. Relative to GBD 2015, we expanded the GBD cause hierarchy by 18 causes of death for GBD 2016.

FINDINGS

The quality of available data varied by location. Data quality in 25 countries rated in the highest category (5 stars), while 48, 30, 21, and 44 countries were rated at each of the succeeding data quality levels. Vital registration or verbal autopsy data were not available in 27 countries, resulting in the assignment of a zero value for data quality. Deaths from non-communicable diseases (NCDs) represented 72·3% (95% uncertainty interval [UI] 71·2-73·2) of deaths in 2016 with 19·3% (18·5-20·4) of deaths in that year occurring from communicable, maternal, neonatal, and nutritional (CMNN) diseases and a further 8·43% (8·00-8·67) from injuries. Although age-standardised rates of death from NCDs decreased globally between 2006 and 2016, total numbers of these deaths increased; both numbers and age-standardised rates of death from CMNN causes decreased in the decade 2006-16-age-standardised rates of deaths from injuries decreased but total numbers varied little. In 2016, the three leading global causes of death in children under-5 were lower respiratory infections, neonatal preterm birth complications, and neonatal encephalopathy due to birth asphyxia and trauma, combined resulting in 1·80 million deaths (95% UI 1·59 million to 1·89 million). Between 1990 and 2016, a profound shift toward deaths at older ages occurred with a 178% (95% UI 176-181) increase in deaths in ages 90-94 years and a 210% (208-212) increase in deaths older than age 95 years. The ten leading causes by rates of age-standardised YLL significantly decreased from 2006 to 2016 (median annualised rate of change was a decrease of 2·89%); the median annualised rate of change for all other causes was lower (a decrease of 1·59%) during the same interval. Globally, the five leading causes of total YLLs in 2016 were cardiovascular diseases; diarrhoea, lower respiratory infections, and other common infectious diseases; neoplasms; neonatal disorders; and HIV/AIDS and tuberculosis. At a finer level of disaggregation within cause groupings, the ten leading causes of total YLLs in 2016 were ischaemic heart disease, cerebrovascular disease, lower respiratory infections, diarrhoeal diseases, road injuries, malaria, neonatal preterm birth complications, HIV/AIDS, chronic obstructive pulmonary disease, and neonatal encephalopathy due to birth asphyxia and trauma. Ischaemic heart disease was the leading cause of total YLLs in 113 countries for men and 97 countries for women. Comparisons of observed levels of YLLs by countries, relative to the level of YLLs expected on the basis of SDI alone, highlighted distinct regional patterns including the greater than expected level of YLLs from malaria and from HIV/AIDS across sub-Saharan Africa; diabetes mellitus, especially in Oceania; interpersonal violence, notably within Latin America and the Caribbean; and cardiomyopathy and myocarditis, particularly in eastern and central Europe. The level of YLLs from ischaemic heart disease was less than expected in 117 of 195 locations. Other leading causes of YLLs for which YLLs were notably lower than expected included neonatal preterm birth complications in many locations in both south Asia and southeast Asia, and cerebrovascular disease in western Europe.

INTERPRETATION

The past 37 years have featured declining rates of communicable, maternal, neonatal, and nutritional diseases across all quintiles of SDI, with faster than expected gains for many locations relative to their SDI. A global shift towards deaths at older ages suggests success in reducing many causes of early death. YLLs have increased globally for causes such as diabetes mellitus or some neoplasms, and in some locations for causes such as drug use disorders, and conflict and terrorism. Increasing levels of YLLs might reflect outcomes from conditions that required high levels of care but for which effective treatments remain elusive, potentially increasing costs to health systems.

FUNDING

Bill & Melinda Gates Foundation.

Measuring progress and projecting attainment on the basis of past trends of the health-related Sustainable Development Goals in 188 countries: an analysis from the Global Burden of Disease Study 2016

BACKGROUND

The UN's Sustainable Development Goals (SDGs) are grounded in the global ambition of "leaving no one behind". Understanding today's gains and gaps for the health-related SDGs is essential for decision makers as they aim to improve the health of populations. As part of the Global Burden of Diseases, Injuries, and Risk Factors Study 2016 (GBD 2016), we measured 37 of the 50 health-related SDG indicators over the period 1990-2016 for 188 countries, and then on the basis of these past trends, we projected indicators to 2030.

METHODS

We used standardised GBD 2016 methods to measure 37 health-related indicators from 1990 to 2016, an increase of four indicators since GBD 2015. We substantially revised the universal health coverage (UHC) measure, which focuses on coverage of essential health services, to also represent personal health-care access and quality for several non-communicable diseases. We transformed each indicator on a scale of 0-100, with 0 as the 2·5th percentile estimated between 1990 and 2030, and 100 as the 97·5th percentile during that time. An index representing all 37 health-related SDG indicators was constructed by taking the geometric mean of scaled indicators by target. On the basis of past trends, we produced projections of indicator values, using a weighted average of the indicator and country-specific annualised rates of change from 1990 to 2016 with weights for each annual rate of change based on out-of-sample validity. 24 of the currently measured health-related SDG indicators have defined SDG targets, against which we assessed attainment.

FINDINGS

Globally, the median health-related SDG index was 56·7 (IQR 31·9-66·8) in 2016 and country-level performance markedly varied, with Singapore (86·8, 95% uncertainty interval 84·6-88·9), Iceland (86·0, 84·1-87·6), and Sweden (85·6, 81·8-87·8) having the highest levels in 2016 and Afghanistan (10·9, 9·6-11·9), the Central African Republic (11·0, 8·8-13·8), and Somalia (11·3, 9·5-13·1) recording the lowest. Between 2000 and 2016, notable improvements in the UHC index were achieved by several countries, including Cambodia, Rwanda, Equatorial Guinea, Laos, Turkey, and China; however, a number of countries, such as Lesotho and the Central African Republic, but also high-income countries, such as the USA, showed minimal gains. Based on projections of past trends, the median number of SDG targets attained in 2030 was five (IQR 2-8) of the 24 defined targets currently measured. Globally, projected target attainment considerably varied by SDG indicator, ranging from more than 60% of countries projected to reach targets for under-5 mortality, neonatal mortality, maternal mortality ratio, and malaria, to less than 5% of countries projected to achieve targets linked to 11 indicator targets, including those for childhood overweight, tuberculosis, and road injury mortality. For several of the health-related SDGs, meeting defined targets hinges upon substantially faster progress than what most countries have achieved in the past.

INTERPRETATION

GBD 2016 provides an updated and expanded evidence base on where the world currently stands in terms of the health-related SDGs. Our improved measure of UHC offers a basis to monitor the expansion of health services necessary to meet the SDGs. Based on past rates of progress, many places are facing challenges in meeting defined health-related SDG targets, particularly among countries that are the worst off. In view of the early stages of SDG implementation, however, opportunity remains to take actions to accelerate progress, as shown by the catalytic effects of adopting the Millennium Development Goals after 2000. With the SDGs' broader, bolder development agenda, multisectoral commitments and investments are vital to make the health-related SDGs within reach of all populations.

FUNDING

Bill & Melinda Gates Foundation.

Healthcare Access and Quality Index based on mortality from causes amenable to personal health care in 195 countries and territories, 1990-2015: a novel analysis from the Global Burden of Disease Study 2015

BACKGROUND

National levels of personal health-care access and quality can be approximated by measuring mortality rates from causes that should not be fatal in the presence of effective medical care (ie, amenable mortality). Previous analyses of mortality amenable to health care only focused on high-income countries and faced several methodological challenges. In the present analysis, we use the highly standardised cause of death and risk factor estimates generated through the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) to improve and expand the quantification of personal health-care access and quality for 195 countries and territories from 1990 to 2015.

METHODS

We mapped the most widely used list of causes amenable to personal health care developed by Nolte and McKee to 32 GBD causes. We accounted for variations in cause of death certification and misclassifications through the extensive data standardisation processes and redistribution algorithms developed for GBD. To isolate the effects of personal health-care access and quality, we risk-standardised cause-specific mortality rates for each geography-year by removing the joint effects of local environmental and behavioural risks, and adding back the global levels of risk exposure as estimated for GBD 2015. We employed principal component analysis to create a single, interpretable summary measure-the Healthcare Quality and Access (HAQ) Index-on a scale of 0 to 100. The HAQ Index showed strong convergence validity as compared with other health-system indicators, including health expenditure per capita (r=0·88), an index of 11 universal health coverage interventions (r=0·83), and human resources for health per 1000 (r=0·77). We used free disposal hull analysis with bootstrapping to produce a frontier based on the relationship between the HAQ Index and the Socio-demographic Index (SDI), a measure of overall development consisting of income per capita, average years of education, and total fertility rates. This frontier allowed us to better quantify the maximum levels of personal health-care access and quality achieved across the development spectrum, and pinpoint geographies where gaps between observed and potential levels have narrowed or widened over time.

FINDINGS

Between 1990 and 2015, nearly all countries and territories saw their HAQ Index values improve; nonetheless, the difference between the highest and lowest observed HAQ Index was larger in 2015 than in 1990, ranging from 28·6 to 94·6. Of 195 geographies, 167 had statistically significant increases in HAQ Index levels since 1990, with South Korea, Turkey, Peru, China, and the Maldives recording among the largest gains by 2015. Performance on the HAQ Index and individual causes showed distinct patterns by region and level of development, yet substantial heterogeneities emerged for several causes, including cancers in highest-SDI countries; chronic kidney disease, diabetes, diarrhoeal diseases, and lower respiratory infections among middle-SDI countries; and measles and tetanus among lowest-SDI countries. While the global HAQ Index average rose from 40·7 (95% uncertainty interval, 39·0-42·8) in 1990 to 53·7 (52·2-55·4) in 2015, far less progress occurred in narrowing the gap between observed HAQ Index values and maximum levels achieved; at the global level, the difference between the observed and frontier HAQ Index only decreased from 21·2 in 1990 to 20·1 in 2015. If every country and territory had achieved the highest observed HAQ Index by their corresponding level of SDI, the global average would have been 73·8 in 2015. Several countries, particularly in eastern and western sub-Saharan Africa, reached HAQ Index values similar to or beyond their development levels, whereas others, namely in southern sub-Saharan Africa, the Middle East, and south Asia, lagged behind what geographies of similar development attained between 1990 and 2015.

INTERPRETATION

This novel extension of the GBD Study shows the untapped potential for personal health-care access and quality improvement across the development spectrum. Amid substantive advances in personal health care at the national level, heterogeneous patterns for individual causes in given countries or territories suggest that few places have consistently achieved optimal health-care access and quality across health-system functions and therapeutic areas. This is especially evident in middle-SDI countries, many of which have recently undergone or are currently experiencing epidemiological transitions. The HAQ Index, if paired with other measures of health-system characteristics such as intervention coverage, could provide a robust avenue for tracking progress on universal health coverage and identifying local priorities for strengthening personal health-care quality and access throughout the world.

FUNDING

Bill & Melinda Gates Foundation.

History of Medical Parasitology and Parasitic Infections in Iran

Parasites and parasitic diseases have been prevalent in Iran according to Iranian ancient scholars and physicians' inscriptions dating back to 865-1496. Some protozoan diseases such as malaria and cutaneous leishmaniasis have been introduced by clinical manifestations and helminthic infections by size and morphology of the worms. Scientific studies of Parasitology started in Iran from 1833, first by foreign physicians and continued from 1909 by Iranian researchers. The pioneer medical parasitologists of Iran were Dr N. Ansari and Dr. Sh. Mofidi who established the Department of Medical Parasitology in the School of Medicine, University of Tehran, 1939. Afterward, a considerable number of researchers and professors of parasitology have been active in training and research works in the fields of medical parasitology throughout the entire nation. At present, some significant parasitic diseases such as bilharsiasis and dracunculiasis are more or less eradicated and malaria is in the elimination phase. The prevalence of most helminthic infections has considerably decreased. Most of the departments of medical Parasitology in Iran are active in training MD, MSPH and PhD students. The Iranian Society of Parasitology established in 1994 is active with many eligible members and its creditable publication, the Iranian Journal of Parasitology, published seasonally since 2006. From 1833, when the scientific studies of Parasitology have started in Iran up to 2013, many researchers have been done on various fields of medical Parasitology and parasitic diseases in Iran and 2517 papers in English and 1890 papers in Persian have been published in national and international scientific journals. In addition, more than 420 books related in the field of medical parasitology field have been published in Persian language.

Genotyping of Hydatid Cyst Isolated from Human and Domestic Animals in Ilam Province, Western Iran Using PCR-RFLP

BACKGROUND

Hydatidosis or cystic hydatid disease is one of the most important diseases in human and animals. Identification of strains is important for improvement of control and prevention of disease. The aim of this study was to determine the strains isolated from human and domestic animals in Ilam Province, Iran, using PCR-RFLP method.

METHODS

Respectively, 30 and 4 animal and human hydatid cysts were collected from different slaughterhouses and hospitals of the province. Protoscolices were separated and their DNA genome was extracted by extraction kit. rDNA-ITS1 of each isolated samples was duplicated by BD1(Forward) and 4s (Reverse) Primers. PCR products were studied by electrophoresis and then were digested using TaqI, HpaII, RsaI and AluI restriction enzymes. RFLP products were studied using electrophoresis on 1% agar gel.

RESULT

A fragment of 1000bp was produced from amplification of rDNA-ITS1 of protoscolices using PCR method. After digestion of PCR product by AluI enzyme, 200bp and 800bp, by RsaI, 655bp and 345bp and by HpaII 700bp and 300bp sizes were obtained. TaqI enzyme had no change in fragment size and it remained 1000bp. Considering the method, Ilam strains was specified as E. granulosus sensu stricto (G1-G3).

CONCLUSIONS

Although sheep strain (G1) is dominated in human and different animal in Iran and the world, but more efforts should be done to clarify the true genotype of Ilam strains specified as E. granulosus sensu stricto (G1-G3).

Assessing the effect of highly cited papers on the impact factor of journals in the field of public health

BACKGROUND

The aim of this study was to appraisal the effect of highly cited papers in the field of public health and find out whether the unusual citations affect the ranking order of the journals in this field or not. A total number of 142 journals titles were listed in Journal Citation Report (ISI Thomson) in the field of "Public, Environmental & Occupational Health". All but one of them had published papers at least for a year from 2009 to 2010. Journal title, number of citations and publication year of 45685 papers were collected from ISI web of knowledge database at December 25, 2011. About half of the papers (23226) had no citations and 89.4% (40835) had less than 6 citations. We concluded that the ranking of journals in the field of public health is not affected by the individual papers with unusual number of citations.

Evaluation of rabbit antibody response against 8 and 16 kDa recombinant subunits of antigen B from Echinococcus granulosus

OBJECTIVE

To immunize rabbits with 12 and 16 kDa recombinant subunits of antigen B from Echinococcus granulosus (E. granulosus) and measuring polyclonal antibody and humoral immune response using ELISA and gel diffusion.

METHODS

Two mentioned antigens were cloned and expressed in expression vector and purified by affinity chromatography. Four young rabbits were selected and challenged intradermally with yielded recombinant antigens. Rabbits' sera were collected post infection and were tested using ELISA and gel diffusion for polyclonal antibody detection 10 days after last injection.

RESULTS

The specific antibody against the recombinant peptides was efficiently produced within 4 weeks post infection.

CONCLUSIONS

Produced recombinants proteins could induce the immune response of the rabbits successfully. This process might improve the clarification of diagnosis and vaccination as regards hydatidosis.

Seroprevalence of human hydatidosis using ELISA method in qom province, central iran

BACKGROUND

The objective of this study was to determine the prevalence of cystic echinococcosis (CE) in Qom Province, central Iran using ELISA test.

METHODS

Overall, 1564 serum samples (800 males and 764 females) were collected from selected subjects by randomized cluster sampling in 2011-2012. Sera were analyzed by ELISA test using AgB. Before sampling, a questionnaire was filled out for each case. Data were analyzed using Chi-square test and multivariate logistic regression for risk factors analysis.

RESULTS

Seropositivity was 1.6% (25 cases). Males (2.2%) showed significantly more positivity than females (0.9%) (P= 0.03). There was no significant association between CE seropositivity and age group, occupation, and region. Age group of 30-60 years encompassed the highest rate of positivity. The seropositivity of CE was 2.1% and 1.2% for urban and rural cases respectively. Binary logistic regression showed that males were 2.5 times at higher risk for infection than females.

CONCLUSION

Although seroprevalence of CE is relatively low in Qom Province, yet due to the importance of the disease, all preventive measures should be taken into consideration.

Heavy Worm Burden of Moniliformis moniliformis in Urban Rats with Histopathological Description

BACKGROUND

Due to scarcity of human reports, we took advantage of the heaviest infection of M. moniliformis in rats, to describe histopathological and microanatomical valuable useful keys while confronting human occurrences.

METHODS

Samples were obtained from captured rats in Tehran, capital of Iran, during two decades. Tissue sections were performed through hematoxylin and eosin staining to describe histopathological changes in rat's intestines.

RESULTS

Totally, nine rats were found infected with M. moniliformis amongst 272 obtained rats. Heavy infection has been distinguished in 2 individuals with parasite burden of 141and 73 adult worms. Cross sections of worms within the lumen show mucosal thickness, infiltration of eosinophilic leukocyte and increase in goblet cells.

CONCLUSION

Beyond the uncommonness of human infection with M. moniliformis unitended infections should not be ignored. Abundance of rats and roaches as definite and intermediate hosts must be considered particularly in countries with poor hygiene.

Molecular Identification and Differentiation of Fasciola Isolates Using PCR- RFLP Method Based on Internal Transcribed Spacer (ITS1, 5.8S rDNA, ITS2)

BACKGROUND

In this study, we used both ITS1 and ITS2 for molecular identification of Fasciola species.

METHODS

The region between 18S and 28S of ribosomal DNA was used in PCR-RFLP method for molecular identification of Fasciola species. Ninety trematodes of Fasciola were collected during abattoir inspection from livers of naturally infected sheep and cattle from Khorasan, East Azerbaijan, and Fars provinces in Iran. After DNA extraction, PCR was performed to amplify region ITS1, 5.8S rDNA, ITS2. To select a suitable restriction enzyme, we sequenced and analyzed the PCR products of F. hepatica and F. gigantica samples from sheep and cattle. Tsp509I fast digest restriction enzyme was selected for RFLP method that caused the separation specifically of Fasciola species.

RESULTS

The fragment approximately 1000bp in all of the Fasciola samples was amplified and then digested with the Tsp509I restriction endonuclease. Seventy F. hepatica and 20 F. gigantica were identified of total 90 Fasciola isolates.

CONCLUSION

The new PCR-RFLP assay using Tsp509I restriction enzyme provides a simple, practical, fast, low cost, and reliable method for identification and differentiation of Fasciola isolates.

Seroepidemiological study of human hydatidosis in meshkinshahr district, ardabil province, iran

BACKGROUND

The aim of this study was to conduct a sero-epidemiological survey in Meshkinshahr, Ardabil Province, northwestern Iran to detect the rate of hydatidosis in the city and nearby villages. Literature shows that no such study has been conducted so far.

METHODS

Overall, 670 serum samples were collected from 194 males and 476 females from patients referred to different health centers of the region. All patients filled out a questionnaire and an informed consent. Sera were analyzed using indirect-ELISA test. Ten µg /ml antigens (Antigen B derived from hydatid cyst fluid), serum dilutions of 1:500 and conjugate anti-human coombs with 1:10000 dilutions were utilized to perform the test. Data analysis was conducted using SPSS software ver. 11.5.

RESULTS

The seroprevalence of human hydatidosis was 1.79% by ELISA test in the region. This rate for females was 1.68% and males 2.6%, respectively. There was no significant difference as regards all factors studied and the seropositivity. According to job, farmers and ranchmen had the highest rate of infection as 3.17%. The sero-prevalence of infection was 2.6%% in illiterate people which showed the highest rate. As regards residency, urban life showed no significant difference with rural life (1.1% vs. 2.58%). Age group of 69-90 yr old, with 4.62% as prevalence had the highest rate of positivity.

CONCLUSION

Obtained sero-prevalence of hydatidosis shows more or less a resemblance to other cities of Iran, although due to the specific condition of the city we expected more rate of sero-positivity.

Establishment of Hymenolepis diminuta Life Cycle to Provide Parasite Mass Production

BACKGROUND

The main object of this experimental work was to practise laboratory production both adult and the larval stage of Hymenolepis diminuta with conventional modification to make further studies easier. MATERIALS #ENTITYSTARTX00026;

METHOD

Adults H. diminuta were collected from urban rats in Tehran, Iran. The beetles became infected using blended gravid segments with flour as bait. Cysticercoids have been saved after precise dissection of invertebrate hosts. The exposure of infected beetles to laboratory rats was performed to establish the life cycle.

RESULT

Out of 57 collected rats, three rats were infected with H. diminuta. Almost all exposed beetles found infected with the larval stage of parasite. About one-month later H. diminuta eggs were seen in stool examination of laboratory rats.

CONCLUSION

Rare human occurrence of H. diminuta along with light level of clinical manifestation of this parasite, underestimate the concerns toward its public health importance. Nowadays, various field of studies, such as biochemistry with special focuses on the capability of H. diminuta tegument absorption have performed apart from parasitological views alone. In the present study, establishment of this parasite life cycle has practically provided the access of adult and cysticercoid stages of the tapeworm in further researches.

Molecular Diagnosis of Strongyloides stercoralis Infection by PCR Detection of Specific DNA in Human Stool Samples

BACKGROUND

Strongyloidiasis is mostly an asymptomatic infection and diagnosis of latent infections is difficult due to limitations of current parasitological and serological methods. This study was conducted to set up a PCR-based method for molecular diagnosis of Strongyloides stercoralis infection by detection of copro-DNA in stool samples.

METHODS

A total of 782 fresh stool samples were collected and examined by agar plate culture. Among those sixteen stool samples, which confirmed to be infected with S. stercoralis were examined as positive control to set up each single and nested PCR, using two primer sets designing to amplify partial ribosomal DNA of S. stercoralis genome. Since, single PCR method yielded higher efficacy in detecting positive samples, in the second step, 30 stool samples, which found negative for S. stercoralis by agar plate culture of single stool sample, were examined by single PCR. Data analysis was performed using McNemar's χ(2) test, with consideration of a P-value of <0.05 as indication of significant difference.

RESULTS

In amplification of DNA extracted from stool samples, single PCR detected S. stercoralis DNA target in all 16 positive samples, while nested PCR amplified DNA in only 75% of samples. In the second step, single PCR amplified S. stercoralis extracted DNA in 5 out of 30 samples which were negative by coproculture.

CONCLUSION

Single PCR method amplifying a short (100bp) target represented more efficacies for detection of S. stercoralis in faecal examination compared to agar plate culture and nested PCR, which amplified longer target.

Evaluation of Fast-ELISA versus standard-ELISA to diagnose human fasciolosis

BACKGROUND

The present study was conducted to evaluate and compare a fast-ELISA (F-ELISA) method versus standard-ELISA (S-ELISA) to diagnose human fasciolosis.

METHODS

Serum samples were obtained from 35 individuals infected with fasciolosis, 27 infected with other parasitoses and 22 from healthy people. The samples were examined with S-ELISA (30-minute incubation periods) and F-ELISA (10-minute incubation periods) for total antibody response against fasciolosis.

RESULTS

The optimum conditions for S-ELISA and F-ELISA were respectively as follows: antigen 10 and 5 µg/mL, sera 1:500 dilution for both, peroxidase-conjugated goat anti-human IgG diluted 1:7000 and 1:10000. Data were analyzed using SPSS version 11.0. Cut-off vale for S-ELISA and F-ELISA was determined as 0.56 and 0.42, respectively. The sensitivity, specificity; positive, and negative predictive values were detected as 97.2%, 100%, 94.6%, and 95.6% for both tests.

CONCLUSION

Cut-off values, sensitivity, specificity, and other important parameters of the two evaluated tests determined that the F-ELISA method could be used with no detectable difference.

The prevalence of honorary and ghost authorships in Iranian bio-medical journals and its associated factors

BACKGROUND

The purpose of this study was to detect the prevalence of ghost and honorary authors and its determinant factors in bio-medical journals of Iran.

METHODS

The study was done in 2009-10 in Tehran, Kerman, and Iran Medical Universities, Iran. We contacted the first or corresponding authors of the papers had published papers in the recent two issues of Iranian Journal of Public Health, Journal of Kerman University of Medical Sciences, and Tehran University Medical Journal. They explored the role of each coauthor and others who had done mouthing for the paper. Then, according to ICMJE criteria, we counted how many of them are real, honorary or ghost author. For the analysis, we utilized two databases. One included articles as the records and the other included authors as the records.

RESULTS

From 124 articles, with 536 authors, 301 (56.1%) were honorary authors. Each article had 4.35 authors on average, while 2.4 of them were honorary authors. The percentage of honorary author in basic science articles was about 6% more than the articles of clinical sciences. Moreover, 89% of articles had at least one honorary author. About 20% of all articles had more than three honorary authors. Besides, 25 (21.43%) authors confessed they had colleague(s) omitted from the authors list, while only one (0.81%) of them met the authorship criteria. The percentage of agreement between the corresponding and the remaining authors on the number of honorary of the authors was about 47.4% (Kappa= 0.27, P= 0.01).

CONCLUSION

It seems that the present data might assist the authorities to make a decisive decision on amending the process of authorship in Iran.

Gene cloning, expression and serological evaluation of the 12-kDa antigen-B subunit from Echinococcus granulosus

A 12-kDa subunit of antigen B from Echinococcus granulosus has recently been cloned, expressed and used in diagnostic ELISA to test human sera for evidence of cystic echinococcosis. The performance of the ELISA based on the recombinant antigen (rAgB) was compared with that of similar assays based on native antigen B (nAgB) or hydatid-cyst fluid. For the preparation of the rAgB, total RNA was extracted from Ec. granulosus protoscoleces so that antigen-B complementary DNA could be synthesised, amplified by PCR, and then cloned into the pQE30 expression vector. The recombinant plasmid was transformed in Escherichia coli and induced using isopropyl-beta-D-thiogalactopyrano-side. Bacterial samples were collected, lysed and then analysed by SDS-PAGE and western blotting. The recombinant protein was purified by affinity chromatography. Although the performance of the ELISA based on cyst fluid appeared identical to that of the assay based on the recombinant antigen (with a sensitivity, specificity, positive predictive value and negative predictive value of 96.0%, 97.0%, 97.2% and 95.5%, respectively), the corresponding results for the ELISA based on nAgB (98.6%, 100%, 100% and 98.5%) were slightly better. Despite this difference (which was not statistically significant), the comparative ease with which large quantities of the recombinant antigen could be produced make the antigen a potentially useful tool in the diagnosis of cystic echinococcosis.

Neglected human fascioliasis case in a visceral leishmaniasis endemic area, north-Western iran

Ardabil Province, northwestern Iran, is endemic for visceral leishmaniasis of Mediterranean type from many years ago. This situation might cause to underestimate other important diseases, which occur sporadically within the same area. In this case, a 6-year-old male patient in this area was treated as infected with visceral leishmaniasis initially with seropositive result for visceral leishmaniasis. Afterwards, histopathological study of crashed material and tissue sections surprisingly revealed numerous liver fasciolid fluke eggs. This case demonstrates that in an area endemic for a given parasitoses, other important infectious diseases must be considered as well.

Ocular dirofilariasis, a case report

Accidental infection with animal filarial worms in humans is a dilemma for clinicians and parasitologists throughout the world. To date a variety of such rare parasitoses have been reported mostly in tropics and subtropics. Human dirofilariasis is among those unusual zoonotic infections that occasionally have been observed in the eye and in subcutaneous areas exhibiting with nodule formation. Filarial worms are transmitted to humans through invertebrate biological vectors such as certain species of mosquitoes. The present report describes a peculiar case of ocular dirofilariasis in a 49-year-old man resident in Iran.

Serological Evaluation of EgAgB16 kDa, a Recombinant Antigen from Echinococcus granulosus for Diagnosis of Human Hydatidosis

BACKGROUND

Regarding that accurate diagnosis of human hydatidosis still needs more investigations, the present study was conducted to clone, express, and evaluate the gene encoding AgB subunits (EgAgB16 kDa) from Echinococcus granulosus (Iranian G1 strain) and its evaluation by ELISA test.

METHODS

DNA was extracted from protoscoleces and was utilized by PCR for strain identification. Total RNA was prepared with RNeasy protect mini kit from E. granulosus (Iranian G1 strain) protoscoleces collected from naturally infected sheep with hydatid cyst. Recombinant AgB16 kDa was produced using pETDuet as vector and evaluated by ELISA method. A panel of sera including hydatid cyst-infected individuals (n=72), healthy individual (n=48), toxoplasmosis (n=4), strongyloidosis (n=4), kala-azar (n=5) and tuberculosis (n=5) were examined using this recombinant antigen.

RESULTS

Recombinant protein was purified by affinity chromatography using His-Tag column. After purification, recombinant protein was confirmed by western blot analysis using His Tag monoclonal antibody or hydatid positive human serum. The sensitivity, specificity; positive and negative predictive values were calculated as 93.5%, 95.6%, 96% and 92.9%, in that order. The cut-off point was detected 0.3 for rAgB16.

CONCLUSION

While the produced recombinant AgB16 kDa showed promising results in diagnosing human hydatidosis, but more investigations should be implemented to reach an accurate gold standard.

Evaluation of the stability of coated plates with antigen at different temperatures and times by ELISA test to diagnose fasciolosis

BACKGROUND

Considering that ELISA method presently is the test of choice for diagnosis of fasciolosis, the present study was undertaken to evaluate the maximum validity of coated plates at different temperatures and different times during one year of evaluation.

METHODS

Serum samples of patients infected with fasciolosis (n=10), hydatidosis (n=5), toxocariasis (n=5), and negative control sera (n=5) were examined. Two series of plates were considered. The first series were coated with Fasciola homogenate Ag 12 ug/ml, and after some steps were blocked with gelatin and preserved at different temperatures as -80°C, -20°C, -4°C and +4°C. The 2(nd) series were treated under the same criteria but were not blocked with gelatin. Each series were examined by ELISA test from 1(st) month to 12(th) month. Sera with 1:125 dilution, and peroxidase-conjugated goat anti-human IgG diluted 1:10000 were considered optimum.

RESULTS

To ease reporting the results and due to many similarities only results related to 1(st), 6(th) and 12(th) months were analyzed and sensitivity, specificity plus cut-off were determined for each series separately.

CONCLUSION

Preserving the coated plates, while unblocked at -80°C for 6-8 months is pertinent and functional and in that case, we can be sure the best out put would be applicable.

Identification and differentiation of Fasciola hepatica and Fasciola gigantica using a simple PCR-restriction enzyme method

Accurate morphological differentiation between the liver fluke species Fasciola hepatica and Fasciola gigantica is difficult. We evaluated PCR-restriction enzyme profiles of internal transcribed spacer 1 (ITS1) that could aid in their identification. Fifty F. hepatica and 30 F. gigantica specimens were collected from different hosts in three provinces of Iran. For DNA extraction, we crushed fragments of the worms between two glass slides as a new method to break down the cells. DNA from the crushed materials was then extracted with a conventional phenol-chloroform method and with the newly developed technique, commercial FTA cards. A primer pair was selected to amplify a 463-bp region of the ITS1 sequence. After sequencing 14 samples and in silico analysis, cutting sites of all known enzymes were predicted and TasI was selected as the enzyme that yielded the most informative profile. Crushing produced enough DNA for PCR amplification with both the phenol-chloroform and commercial FTA card method. The DNA extracted from all samples was successfully amplified and yielded a single sharp band of the expected size. Digestion of PCR products with TasI allowed us to distinguish the two species. In all samples, molecular identification was consistent with morphological identification. Our PCR-restriction enzyme profile is a simple, rapid and reliable method for differentiating F. hepatica and F. gigantica, and can be used for diagnostic and epidemiological purposes.

The present status of human helminthic diseases in Iran

Over the last few decades there have been several marked changes in the human helminthiases found in Iran. Fascioliasis is emerging as an important chronic disease of humans, especially in the northern province of Gilan (where outbreaks in 1989 and 1999 involved >7000 and >10,000 cases, respectively) and, more recently, in the western province of Kermanshah. In contrast, no cases of urinary schistosomiasis, a disease that once affected thousands of individuals in south-western Khuzestan province, have been reported in Iran in recent years, and no cases of dracunculiasis have been seen in the country since the mid-1970s. Approximately 1% of all admissions to surgical wards are attributable to cystic echinococcosis, which is still considered endemic, but only a few cases of alveolar echinococcosis have been recorded. Over the last decade, there appears to have been a generally downward trend in the incidence of intestinal helminthiases in Iran. Recent estimates of the prevalences of ascariasis and strongyloidiasis, for example, lie between just 0.1% and 0.3%, and <1% of the population now appears to be infected with hookworm. In contrast, human infection with Hymenolepis and Enterobius remains relatively common. There have been a few case reports of toxocariasis and a few sero-epidemiological investigations of this disease but problems in accurate diagnosis have prevented good estimates of the general prevalence of this nematode infection. Just nine cases of pentastomiasis (all caused by Linguatula), 12 of dirofilariasis, one of gongylonemiasis, and three of moniliformiasis have been formally recorded in Iran.

Comparison of enzyme-linked immunosorbent assay and indirect immunofluorescence assay in the diagnosis of human strongyloidiasis

BACKGROUND

An enzyme-linked immunosorbent assay (ELISA) and indirect immunofluorescence assay (IFA) were evaluated for serological diagnosis of human strongyloidiasis.

METHODS

Serum specimens obtained from 46 individuals infected with Strongyloides stercoralis, 37 healthy persons and 381 persons with other parasitic infections were tested using an IgG-ELISA that used crude antigen of S. stercoralis filariform larvae and an IFA. Test sera were pre-incubated with antigens from Ascaris, Toxocara and hydatid protoscolices to remove non-specific antibodies.

RESULTS

The sensitivity, specificity, positive predictive value and negative predictive value for ELISA were 93.5%, 96.1%, 72.9% and 99.2%, respectively, and those for IFA were 87%, 90.1%, 49.4% and 98.4%, respectively. Both assays showed false positivity in hydatidosis, ascariasis and toxocariasis; however, this was less common with ELISA.

CONCLUSION

ELISA method using filariform larval antigen may be a sensitive and specific test for human strongyloidiasis, and may be preferable to IFA.

Helminth parasites of the wild boar, Sus scrofa, in Luristan province, western Iran and their public health significance

Seven helminth species were obtained from 12 wild boars (Sus scrofa) during a survey from 2000 to 2001 in Luristan province, western Iran. These species include the cestode larvae Cysticercus tenuicollis (25%), C. cellulosae (8.3%), the nematodes Metastrongylus apri (41.6%), M. pudendotectus (16.6%), M. salmi (8.3%), Trichuris suis (8.3%) and the acanthocephalan Macracanthorhynchus hirudinaceus (41.6%). No trematodes were found. Seven wild boars (58.3%) were identified as having at least one helminth species. A single infection was detected in 16.6% of cases, but a three species infection covered the highest rank (25%). All these helminths have been reported from other areas of Iran including the north, northeast and southwest, but not in Luristan. Among seven helminths identified, at least three species are transmissible to humans. The public health significance of these helminths is discussed.

Comparison of adult somatic and cysteine proteinase antigens of Fasciola gigantica in enzyme linked immunosorbent assay for serodiagnosis of human fasciolosis

Fasciolosis caused by Fasciola hepatica and Fasciola gigantica is one of the major public health problems in the world and in Iran. Considering that stool examination for Fasciola eggs is not a sensitive method and immunodiagnosis methods are more applicable for this purpose, so the present study was conducted to compare the somatic (S) and cysteine proteinase (CP) antigens of F. gigantica in IgG-ELISA to diagnose human fasciolosis. Serum samples obtained from 100 individuals collected during the fasciolosis outbreak in 1999 in the Gilan province of Northern Iran that were coprologically positive for fasciolosis were analyzed by IgG-ELISA. Sera from healthy control individuals, not infected with any parasitic diseases (n=50) and from others with different parasitic infections including hydatidosis (n=40), toxocariosis (n=20), amoebiosis (n=10), and malaria (n=5) were examined as well. The cut-off point for (S) and CP was 0.40 and 0.35, respectively. All 100 individuals that showed clinical manifestations of fasciolosis, were also seropositive using both antigens, whereas all 50 non-infected controls were seronegative, therefore the sensitivity of the test was 100% for both antigens. The specificity of (S) and CP antigens were calculated as 96.9 and 98.4%, respectively. The positive and negative predictive values of the test regarding (S) antigen were 96 and 100%, whereas these values as for CP antigen were 98 and 100% correspondingly. Two individuals with hydatidosis and two with toxocariasis had antibodies that were reactive against (S) antigen, whereas concerning CP antigen, one individual with hydatidosis and another with toxocariasis showed cross-reactivity against it. We have demonstrated that altogether CP antigen provides a more conclusive diagnosis as possessing lower cut-off and enabling better to discriminate between seronegative and seropositive subpopulations.