Iranian Journal of Parasitology
Volume:16 Issue: 2, Apr-Jun 2021

One of the main obstacles to malaria control in the world has been the emergence of resistance in Plasmodium falciparum to chloroquine and other anti-malarial drugs. This study aimed to review studies in Iran on resistance in P. falciparum and P. vivax to drugs, and to reveal the mechanisms and molecular markers of resistance of these two species.

The databases of PubMed, Scopus, Google Scholar, Magiran, and reputable Iranian journals were searched to find published studies on the resistance in P. falciparum and P. vivax to antimalarial drugs in Iran.

There is a significant relationship between resistance to chloroquine in P. falciparum and the emergence of K76T mutation in the P. falciparum chloroquine-resistance transporter gene in Iran. Resistance to sulfadoxine-pyrimethamine (SP) in P. falciparum is also significantly associated with the development of mutations in the dihydrofolate reductase and dihydropteroate synthase genes. Resistance to chloroquine in P. vivax has not been reported in Iran and it is used as a first-line treatment for P. vivax malaria.

P. falciparum has become resistant to chloroquine in different regions of Iran and is not currently used to treat malaria. Besides, cases have emerged of P. falciparum resistance to SP in different parts of southern Iran, and SP is not administered alone for treating P. falciparum.

Leishmania is a mandatory intracellular pathogen and causing neglected disease. Hence, protection against leishmaniasis by a development vaccine is an important subject. This study aimed to design a poly-epitope vaccine for cutaneous leishmaniasis.

The present study was conducted in the Parasitology Department of Tarbiat Modares University, Tehran, Iran during 2017-2019. Several bioinformatics methods at online servers were used for prediction of different aspects of poly-epitope, including, physico-chemical attributes, allergenicity, antigenicity, secondary and tertiary structures, B-cell, T-cell and MHC (I, II) potential epitopes of LACK, LEIF, GP63 and SMT antigens of L. major.

After designing the construct (GLSL), the outputs of PTM sites demonstrated that the poly-epitope had 57 potential sites for phosphorylation. Furthermore, the secondary of GLSL structure includes 59.42%, 20.94% and 19.63% for random coil, extended strand and alpha-helix, respectively. The GLSL is an immunogenic protein with an acceptable antigenicity (0.8410) and non-allergen. Afterward, 20 potential epitopes of LACK, LEIF, GP63 and SMT antigens were linked by a flexible linker (SAPGTP), then was synthesized, and sub-cloned in pLEXY– neo2. The results were confirmed the expression of 38.7 kDa poly-epitope in secretory and cytosolic sites, separately.

A good expression in the L. tarentulae and confirmation of the GLSL poly-epitope could be a basis for developing a vaccine candidate against leishmaniasis that should be confirmed via experimental tests in BALB/c mice.

Parasitic infections are widespread in sheep farms of the Russian Federation, including Siberia. The infection of sheep with helminths and parasitic arthropods with a range of 70% to 100% in different regions, contributes to a decrease in the productivity and quality of products, and even death of animals. This study aimed to formulate drugs with pronounced parasiticidal effects based on ivermectin and albendazole, widely used to treat animal entomoses and helminth infections.

New formulations in the form of solid dispersed compositions were prepared by mechanochemical modification of ivermectin and albendazole using arabinogalactan polysaccharide. The efficacy of preparations on gastrointestinal strongylosis and monieziosis, and melophagosis of sheep was determined by parasitological examination and analysis of feces and urine.

The new formulations demonstrated increased solubility and parasiticidal activity due to the formation of inclusion complexes when interact with water. The maximum efficacy values ​​(> 95% efficiency) against intestinal Strongylida and Moniezia expansa, and ectoparasitic Melophagus ovinus were seen in doses lower than the recommended doses of the starting drugs.

The increased parasiticidal activity of innovative compositions can be explained by increased water solubility and bioavailability of the preparations, due to formation of inclusion complexes. The results of this study suggests the possibility of a significant reduction in the dosages of composed substances without losing their parasiticidal activity.

This study aimed to analyze cultures of mononuclear (MN) cells with Giardia lamblia to determine the levels of the cytokines IFN-γ and TGF-β and the functional activity of MN cells after incubation with cytokines.

This study was conducted in 2018 in Barra do Garças, Mato Grosso State, Brazil. Blood samples were collected from 60 healthy volunteer donors to obtain leukocytes. The levels of IFN-γ and TGF-β were quantified in trophozoite cell culture supernatants. Superoxide release, phagocytosis, microbicidal activity, apoptosis and intracellular calcium release were analyzed.

The cytokines evaluated were detected in the culture supernatant of MN cells and G. lamblia. Regardless of the type of cytokine, MN cells increased superoxide release in the presence of G. lamblia. Phagocytosis, microbicidal activity and apoptosis were higher when MN phagocytes were treated with cytokines. The highest microbicidal activity and apoptosis rates were observed in MN cells cultured with TGF-β. IFN-γ increased the release of intracellular calcium by MN phagocytes.

Cytokines play a beneficial role in the host by activating MN cells against G. lamblia. In addition, phagocytosis causes G. lamblia death and that the modulation of the functional activity of blood MN phagocytes by cytokines is an alternative mechanism for eliminating G. lamblia.

Cystic echinococcosis (CE) is a zoonotic disease caused by infection with Echinococcus granulosus. Toll-like receptors (TLRs) as the first line of defense against various parasites play a critical role in sensing and triggering anti-parasite responses.

The study was conducted at the Department of Pathobiology, Faculty of Veterinary Medicine, Ferdowsi University of Mashhad, Iran in 2019. Ovine peripheral blood mononuclear cells (PBMCs) were stimulated with hydatid cyst-derived antigens including hydatid cyst fluid (HCF), germinal layer antigens (GL), somatic and excretory/secretory (ES) products of protoscoleces (PSC). To investigate whether the expression of TLR2 and TLR4 was altered during exposure to these antigens, PBMCs were stimulated with two different concentrations at different time points.

After exposure of PBMCs to ES and somatic antigens of protoscoleces (PSC) the expression of TLR2 and TLR4 was down-regulated in comparison with control group. Similarly, HCF markedly down-regulated TLR2 and TLR4 transcripts independent of dose and time. GL antigens significantly down-regulated TLR2, while TLR4 expression was up-regulated as compared with control group.

Hydatid cyst-derived antigens could dysregulate the expression of TLR2 and TLR4 in ovine PBMCs, suggesting a possible mechanism to suppress host immunity to establish chronic infection.

Toxoplasma gondii is a zoonotic obligatory intracellular protozoan parasite that infects a wide range of warm-blooded species. This study aimed to obtain further information on the role of T. gondii infection in ruminant abortion (sheep, goats and cattle) using bioassay and PCR methods in Mazandaran province, northern Iran.

Overall, 104 aborted fetuses (52 bovine, 48 ovine, 4 caprine) were collected at different stages of gestation during the lambing seasons in various parts of Mazandaran Province from Mar 2016 to May 2017. Brains of 104 aborted fetuses were bioassayed in female BALB/c mice. DNA was extracted from all brain samples using phenol-chloroform-isoamyl Alcohol instructions. RE gene was used for detection all of T. gondii DNA by conventional PCR assay.

The results of the bioassayed samples were negative because no tachyzoites or cyst were observed in the peritoneal and brain specimens of the mice. The detection of T. gondii DNA was confirmed by observation of a 529 bp band in 15 out of 104 fetuses (14.4%). The highest prevalence rate of T. gondii detected from sheep (16.6%) followed by cattle (13.4%) and goats (0%). The highest prevalence of the infection was observed in east area, while the lowest prevalence of the infection was observed in west area.

T. gondii infection may partly be responsible for abortion and economic losses in livestock husbandry in this region. Therefore, further additional researches such as genotyping T. gondii and designing control strategies for improving management in livestock flocks are necessary.

According to the WHO (2019), more than 1.5 billion people worldwide are infected with soil-transmitted parasites. Previous research in the Federation of Bosnia and Herzegovina (FB&H) was mainly conducted in the area of the Sarajevo Canton. Therefore, the aim of the research was to explore contamination of soil and vegetation with developmental forms of parasites in the other cantons of FB&H.

Between Apr and Oct 2018, a total of 1,618 soil and vegetation samples were taken from 386 different locations in the 9 cantons of the FB&H.

Positive samples were observed, 65/66 (98.48%) municipalities/cities and on 239/386 (61.92%) locations. Out of 1,618 samples taken in total (1,263 soil samples and 355 vegetation samples), 357 (22.06%) were positive, out of which 337 (26.68%) and 20 (5.63%) were soil and plant samples, respectively. In total, the following adult and developmental forms were identified: Taeniidae eggs (7.30%), Toxocara spp. eggs (62.08%), Ancylostomatidae eggs (25.00%), Trichuris spp. eggs (9.55%), Capillaria spp. eggs (3.37%), Toxascaris leonina eggs (1.40%), Nematodes larvae (19.38%), Giardia duodenalis cysts (5.06%), Cryptosporidium spp. oocysts (1.4%), oocysts and cysts of different species of Protozoa (3.93%).

The identified developmental forms of parasites pose a permanent threat to human health. It is necessary to carry out measures to reduce the contamination of soil and vegetation in coordination with systematic solutions (legislation), paralelly with contribution of animal owners, veterinarians, physicians, ecologists, parents and all the others involved in this issue.

Trichomoniasis, caused by Trichomonas vaginalis protozoan, may lead to clinical or subclinical urethritis or prostatitis in men. Despite the importance of men in the epidemiology of trichomoniasis, there is little information about this topic. This epidemiological study was performed on men in Hamedan, western Iran.

During Oct 2018 to Mar 2019, 214 male individuals, presenting to the Urology Clinic of Shahid Beheshti Hospital in Hamadan, were enrolled and evaluated for trichomoniasis. First-voided urine specimen was used for detection of T. vaginalis infection using molecular and parasitological methods.

Trichomoniasis was detected in 10 of 214 male participants (4.7%, 95% CI: 7.5-1.8%) using PCR assay. Culture and wet mount preparation of urine sediment were unable to isolates any T. vaginalis parasite. Nine of the 10 infected men were married, and six of them were ≥49 yr of age. Urinary frequency and dysuria were the most complaints (80%) among infected individuals.

Given the notable prevalence of the infection, the prevalence of male trichomoniasis will be underestimated if only conventional diagnostic methods are used. Therefore, the risk of infection as well as the molecular survey of T. vaginalis infection should be considered in men with or without clinical symptoms.

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.

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.

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.

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.

The use of antimalarial drugs with number of compounds in combination form may potentiate each other's activity.

This study was conducted in the School of Public Health, Tehran University of Medical Sciences, Tehran, Iran in 2018. It was based on two methods including in vivo and in vitro tests with aim of considering interaction between chitosan and chloroquine against Plasmodium berghei and P. falciparum parasites using different ratios of the agents with ED50s and IC50s baselines.

Administrating 10 and 20 mg/kg (mouse body weight) of chitosan alone to the P. berghei –infected mice up to 4 successive days resulted in 37% and 45% inhibition of P. berghei respectively, while employing the compound with chloroquine in combination form with ratios of 90/10 and 70/30 (chloroquine/chitosan) had a considerable potentiation including 71.58% and 83.85% inhibition effectiveness against P. berghei. Moreover, 20 mg/L (CCM) concentration of chitosan alone could eliminate 69.55% of P. falciparum in culture medium while in combination with chloroquine in ratios of 90/10 (chloroquine/chitosan) had considerable potentiation including 79.14% inhibition effectiveness. Mean survival time of those mice received combination therapy in ratios of 90/10 and 70/30 (chloroquine/chitosan) was longer than those took up mono therapy of either chloroquine or chitosan based on their ED50s doses.

Interaction between chloroquine and chitosan showed considerable potentiation in combination form against either P. berghei or P. falciparum using in vivo and in vitro tests respectively. Meanwhile, interaction between the above mentioned agents resulted in a notable survival time for those P. berghei-infected mice treated with the combination.

This study was performed to determine the prevalence and to identify precisely Toxocara spp., which infects feral cats in Alexandria, Egypt based on morphological and molecular approaches.

This cross-sectional study was carried out on 100 feral cats trapped from different areas of Alexandria during 2018. Adult male and female worms were recovered from small intestinal contents after euthanasia and dissection of cats. Distinct morphological features were initially determined using available keys, and then after amplification and sequencing of the mitochondrial NADH dehydrogenase subunit 1 (nad1) gene was carried out and phylogenetic trees were constructed. 

Forty out of 100 cats were infected with Toxocara spp. Intensity of infection ranged from 1 to 9 worms/cat, with a mean of 2.27±1.6. All isolates were confirmed as T. cati based on morphological features and the sequence of nad1 gene. Results of the current study clearly show that Egyptian T. cati isolate examined herein is genetically similar to those recorded in other countries.

The current work revealed high prevalence of T. cati in feral cats in the study area. This is the first genetic study that confirms T. cati from feral cats in Egypt. In addition, it demonstrated the suitability and need of genetic markers such as nad1 for identification of Toxocara spp. Furthermore highlights the public health importance of T. cati in Egypt.

A specific treatment has not yet developed for cryptosporidiosis, and some of the used drugs had side effects in immunodeficient patients. The goal of an appropriate remedy is to remove symptoms and improve immune responses in hosts. The current study was designed to evaluate the therapeutic efficacy of Artemisia spicigera ethanolic extract in experimentally infected immunosuppressed mice.

Thirty six NMRI mice, 4-6 wk old, were randomly divided into six equal groups. C1: uninfected, treated control; C2: infected, untreated control; T1, T2, T3, and P: infected, treated with 0.2, 2, and 20 mg/ml extract, and 5mg/ml paromomycin, respectively. Mice were experimentally infected by oral administration of 104 oocysts/animal of Cryptosporidium parvum and treated orally for eight days per 12h, starting 12h before experimental infection. The presence of oocyst shedding, weight gain/loss, and the histopathology of ileum sections were examined.

Results revealed that oocyst shedding was significantly (P<0.05) reduced in treatment groups. There was no significant difference between the mean of weight gain/loss in the infected control and treated groups. Histopathological analysis of ileum sections further supported the parasitological findings.

Artemisia spicigera had acceptable efficacy as a therapeutic agent for cryptosporidiosis.

Theileria camelensis and T. dromedarii are parasitic protozoans reported by several studies as specific species that infect the one-humped camel (Camelus dromedarius). However, other findings casted significant doubts on the true identity of the causative species of theileriosis in camels. Therefore, the present study was conducted to investigate of T. camelensis and T. dromedarii in one humped camels in Iraq during Apr-Oct 2017.

Blood samples for DNA extraction were obtained from 181 slaughtered camels. Molecular investigation was performed following the amplification of 18S rRNA gene by conventional PCR technique. DNA sequencing was then utilized only for the positive samples to confirm the infection with the Theileria species.

Nine (4.97%) out of 181 examined samples showed a positive result to infection with Theileria spp., and all these appeared as a T. annulata when subjected to DNA amplification and sequencing techniques. There was a complete absence of any new sequence outside the known species.

Most of Theileria infection in camels in the study area is caused by T. annulata and no other causative agents like T. camelensis or T. dromedarii.

Free-living amoeba (FLA) belonging to Acanthamoeba spp., Naegleria, and Balamuthia mandrillaris are the soil-born protozoa. This study aimed to survey the occurrence of FLA, including Acanthamoeba spp., B. mandrillaris, Vermamoeba spp., and Naegleria spp., in soil samples collected from various districts of Mazandaran Province (Northern Iran) from July to December 2018.

Overall, 118 soil samples from the recreational and public places were surveyed for the existence of Acanthamoeba spp., Vermamoeba, Naegleria, and B. mandrillaris using both morphological key and molecular tools with genus-specific primers of JDP1, NA, ITS1, and Bal, respectively. To verify the taxonomic status of isolated amoeba, the phylogenetic tree was made based on sequences of 18S rRNA by MEGA (5.05) software with the maximum likelihood model.

Overall, 61/118 samples (51.6%) were contaminated with FLA, and based on the sequencing data, 29 isolates were successfully sequenced. Among the samples, all isolated Acanthamoeba (52.4%) belonged to the T4 genotype with amplification of the DF3 region (18S rRNA gene). Internal transcribed spacer (ITS) sequencing revealed the presence of one strain of Naegleria americana. Twenty-eight V. vermiformis were also confirmed based on Nuclear SSU rDNA. Morphological survey and PCR assay did not show any positive samples for B. mandrillaris.

The present study indicates the occurrence of FLA in soil sources of the recreational and public places in Mazandaran province that it can be a severe risk to human health. Thus, more studies are expected to survey the infection source in patients with FLA-related diseases.

Human toxocariasis is a neglected parasitic disease in most countries including Iran. Among different clinical forms of toxocariasis, ocular toxocariasis (OT) is an important disease resulting in severe vision loss. However, the prevalence and incidence of OT are currently unclear in Iran. This study aimed to determine the prevalence of ocular toxocariasis among patients with uveitis in the Northeast of Iran.

From 2015 to 2017, 510 patients with uveitis referred to Khatam-al-Anbia, a tertiary eye hospital at Mashhad, Iran were examined for OT. Serum samples of the suspected patients were obtained and evaluated for IgG against Toxocara canis using ELISA test. Anti-Toxocara IgG positive serums were further investigated using confirmatory Western blotting (WB) analysis.

Twenty patients had pathologic changes and clinical presentations in the anterior and posterior segments of their eyes and they were clinically diagnosed ocular toxocariasis. Among the 20 patients, 2 (10%) patients showed IgG antibody against Toxocara canis on ELISA as well as on WB test. The calculated prevalence of ocular toxocariasis was about 0.4%.

Ocular toxocariasis can be diagnosed both clinically and serologically in Mashhad, northeastern Iran. Although OT is a rare pathologic eye disease, it should be considered as one of the important cause of infectious posterior uveitis.

This study was designed to determine the frequency of hydatidosis in Khuzestan Province, Iran and to evaluate the antibody changes in infected individuals after treatment.

Overall, 454 sera were collected from health centers of Khuzestan Province, southern Iran (from 2013 to 2018). Demographic data such as age, gender and history of disease were recorded. Serum samples were investigated for antibody against CE by ELISA using antigen B. Thirty six of cases were followed up after treatment.

Among the 454 evaluated cases, antibody against CE was detected in 184 (40.52%) including 115 (62.5%) females and 69 (37.5%) males. Age distribution was from 8-97 yr, the highest prevalence of hydatid cyst was observed in age group 40-49 years. Liver was the most infected organ (76.63%). Relapse of CE occurred in 23 of patients. In the majority of patients the antibody decreased, whereas in some cases increased CE antibody observed during post-treatment follow up.

Current study indicated the high prevalence of hydatidosis and rate of relapse after treatment among suspected patients. Therefore, long periods and regular follow-up of patients after treatment is necessary and for these monitoring, antibody assay can be an appropriate method.

This study aimed to investigate the prevalence, intensity and risk factors (age and gender) promoting the intestinal helminthic infections of the Domestic mountain ponies and Balkan donkeys in Serbia.

Prevalence, intensity and risk factors influencing helminth infection in horses (n=39) and donkeys (n=18) at the site of Nature Park Stara Planina, were studied from May to Sep 2015. The presence of one or several gastrointestinal helminth species was confirmed by faecal flotation in 97.43% of horses and 88.88% of donkeys included in the monitoring. The identified helminth species were Trichostrongylus axei, Strongylus edentatus, S. vulgaris, Parascaris equorum, Dictyocaulus arnfieldi and Anoplocephala magna in 84.61%, 46.15%, 5.13%, 58.97%, 94.87% and 38.46% of horses, respectively. The significant association of infection with P. equorum and sex of horses was established. (χ2=13.33, P<0.01).

The prevalence of parasitic helminths identified in donkeys was the following: D. arnfieldi, T. axei, Pa. equorum, S. vulgaris, A. margna and Strongyloides westeri in 55.55%, 38.89%, 27.78%, 22.22% and 22.22% of donkeys, respectively. Moreover, the mean faecal egg count was higher in donkeys (369.9 EPG - egg per gram) than in horses (250.2 EPG). The association between the age and the mean EPG was significant (P<0.05) in both equine species.

The results of the investigation provided basic information that can be helpful for planning strategic control of nematode infection in equine population in Nature Reserves in Serbia.

The migration of humans and climatic and environmental changes cause the emergence of infectious diseases. This study aimed to investigate the changes in the molecular epidemiology of the Echinococcosis disease in the southeast region of Turkey after migrations.

Overall, 159 tissues samples were taken from suspected cases of Echinococcosis at the Kilis State Hospital in the southeast region of Turkey. All of the tissues samples were analyzed using histopathology methods, PCR, Real-time PCR methods, DNA sequencing, and phylogenetic analyses in laboratories.

The positivity values of the histopathology, the polymerase chain reaction, and the Real-time PCR methods were found to be 14.5% (23/159), 15.7% (25/159), and 16.9% (27/159), respectively. 32.0 % (8/25) E. multilocularis of Echinococcus isolates and 68% (17/25) E. granulosus of Echinococcus isolates were identified using PCR methods. 58.8% (10/17) of the E. granulosus isolates were found to be Genotype 1% and 41.2% (7/17) E. granulosus isolates were found to be Genotype 3.

Molecular methods play an important role in the epidemiology, treatment, and diagnosis of diseases. Increasing immigration in a geographical area may create social, economic, and health problems in that area. For this reason, epidemiological studies of infectious diseases should be updated in areas with immigration.