The effects of killer cell immunoglobulin-like receptor (KIR) genes on susceptibility to severe COVID-19 in the Iranian population.

BACKGROUND: Variations in the innate and adaptive immune response systems are linked to variations in the severity of COVID-19. Natural killer cell (NK) function is regulated by sophisticated receptor system including Killer-cell immunoglobulin-like receptor (KIR) family. We aimed to investigate the impact of possessing certain KIR genes and genotypes on COVID19 severity in Iranians. KIR genotyping was performed on 394 age/sex matched Iranians with no underlying conditions who developed mild and severe COVID- 19. The presence and/or absence of 11 KIR genes were determined using the PCR with sequence specific primers (PCR-SSP). RESULTS: Patients with mild symptoms had higher frequency ofKIR2DS1 (p = 0.004) and KIR2DS2 (p = 0.017) genes compared to those with severe disease. While KIR3DL3 and deleted variant of KIR2DS4 occurred more frequently in patients who developed a severe form of the disease. In this study, a significant increase of and B haplotype was observed in the Mild group compared to the Severe group (respectively, p = 0.002 and p = 0.02). Also, the prevalence of haplotype A was significantly higher in the Severe group than in the Mild group (p = 0.02). CONCLUSIONS: These results suggest that the KIR2DS1, KIR2DS, and B haplotype maybe have a protective effect against COVID-19 severity. The results also suggest the inhibitory gene KIR2DL3 and haplotype A are risk factors for the severity of COVID-19.

Discordance Therapeutic Protocol of Cystic Echinococcosis With WHO Guideline: A Descriptive Study Based on Liver Ultra-Sonographic Data in North Khorasan Province, Northeastern of Iran.

BACKGROUND: Cystic echinococcosis (CE), a helminth-associated zoonosis caused by Echinococcus granulosus, poses a significant public health problem, particularly in pastoral-rearing regions. The lack of uniform guidelines led to variations in CE management. Based on ultrasound data, the World Health Organization Informal Working Group on Echinococcosis (WHO-IWGE) classification system categorizes cysts into active, transitional, and inactive groups. This study assesses whether the therapeutic approach from liver human operation cases in North Khorasan province aligns with the WHO-IWGE reference based on ultrasound data. METHODS: The research is based on ultrasound data from liver CE human operation cases collected between 2018 and 2022. This retrospective study investigates the therapeutic protocol for (CE) in North Khorasan Province, Iran, comparing it with the WHO-IWGE guidelines. We collect data from previously registered patients' medical information from our studied area's main CE surgical hospital. Moreover, as the first hospitalized survey in Iran, this study reveals insights into patient demographics, cyst stage prevalence, and treatment modalities. RESULTS: Notably, more than half of the patients were treated for CE1 stage cysts, and CE4 cases, which generally do not require surgery, underwent open surgery. The results suggest a need for adherence to the "watch-and-wait" approach in specific cases. All patients underwent successful surgeries, but we do not have access to follow-up data from patients after discharge. CONCLUSIONS: This descriptive study contributes to understanding the implementation of WHO guidelines in a regional context, shedding light on the challenges and variations in CE management. It seems, retraining courses for surgeons are required to update their knowledge of standard CE diagnostic and treatment methods.

Potential therapeutic targets shared between leishmaniasis and cancer.

The association of leishmaniasis and malignancies in human and animal models has been highlighted in recent years. The misdiagnosis of coexistence of leishmaniasis and cancer and the use of common drugs in the treatment of such diseases prompt us to further survey the molecular biology of Leishmania parasites and cancer cells. The information regarding common expressed proteins, as possible therapeutic targets, in Leishmania parasites and cancer cells is scarce. Therefore, the current study reviews proteins, and investigates the regulation and functions of several key proteins in Leishmania parasites and cancer cells. The up- and down-regulations of such proteins were mostly related to survival, development, pathogenicity, metabolic pathways and vital signalling in Leishmania parasites and cancer cells. The presence of common expressed proteins in Leishmania parasites and cancer cells reveals valuable information regarding the possible shared mechanisms of pathogenicity and opportunities for therapeutic targeting in leishmaniasis and cancers in the future.

The host mTOR pathway and parasitic diseases pathogenesis.

The mechanistic (or mammalian) target of rapamycin (mTOR) is considered as a critical regulatory enzyme involved in essential signaling pathways affecting cell growth, cell proliferation, protein translation, regulation of cellular metabolism, and cytoskeletal structure. Also, mTOR signaling has crucial roles in cell homeostasis via processes such as autophagy. Autophagy prevents many pathogen infections and is involved on immunosurveillance and pathogenesis. Immune responses and autophagy are therefore key host responses and both are linked by complex mTOR regulatory mechanisms. In recent years, the mTOR pathway has been highlighted in different diseases such as diabetes, cancer, and infectious and parasitic diseases including leishmaniasis, toxoplasmosis, and malaria. The current review underlines the implications of mTOR signals and intricate networks on pathogen infections and the modulation of this master regulator by parasites. Parasitic infections are able to induce dynamic metabolic reprogramming leading to mTOR alterations in spite of many other ways impacting this regulatory network. Accordingly, the identification of parasite effects and interactions over such a complex modulation might reveal novel information regarding the biology of the abovementioned parasites and might allow the development of therapeutic strategies against parasitic diseases. In this sense, the effects of inhibiting the mTOR pathways are also considered in this context in the light of their potential for the prevention and treatment of parasitic diseases.

The use of proteomics for the identification of promising vaccine and diagnostic biomarkers in Plasmodium falciparum.

Plasmodium falciparum is the main cause of severe malaria in humans that can lead to death. There is growing evidence of drug-resistance in P. falciparum treatment, and the design of effective vaccines remains an ongoing strategy to control the disease. On the other hand, the recognition of specific diagnostic markers for P. falciparum can accelerate the diagnosis of this parasite in the early stages of infection. Therefore, the identification of novel antigenic proteins especially by proteomic tools is urgent for vaccination and diagnosis of P. falciparum. The proteome diversity of the life cycle stages of P. falciparum, the altered proteome of P. falciparum-infected human sera and altered proteins in P. falciparum-infected erythrocytes could be proposed as appropriate proteins for the aforementioned aims. Accordingly, this review highlights and proposes different proteins identified using proteomic approaches as promising markers in the diagnosis and vaccination of P. falciparum. It seems that most of the candidates identified in this study were able to elicit immune responses in the P. falciparum-infected hosts and they also played major roles in the life cycle, pathogenicity and key pathways of this parasite.

Genotyping determination of Acanthamoeba strains: an original study and a systematic review in Iran.

This study aimed to detect the presence of Acanthamoeba spp. in different water resources of Zahedan, southeast of Iran, and also systematically reviewed all publications regarding Acanthamoeba in Iran (2005-2018). Fifty water samples were collected from different water resources in Zahedan. The positive samples were identified morphologically and subjected to polymerase chain reaction (PCR) using fragments of 18S rRNA. In the systematic review, data collection using particular terms was carried out using the following electronic databases including Science Direct, ISI Web of Science, MEDLINE, EBSCO, Scopus, and Google Scholar. A total of 17 (34%) samples were positive for Acanthamoeba spp., and nucleotide sequencing indicated that 15 samples (88.23%) belonged to the T4 genotype and the rest belonged to the T5 genotype. A total of 39 studies reported genotyping of Acanthamoeba spp. from various geographical areas of Iran and revealed that T4 (35 studies), T5 (19 studies), T3 (11 studies), T11 (8 studies), and T2 (6 studies) genotypes were the most prevalent in Iran. The T4 genotype of Acanthamoeba is a prevalent free-living amoeba and widely distributed not only in Zahedan but also in other provinces of Iran. Phylogenetic analysis reveals that A. castellanii and A. griffini predominantly colocalize with the T4 genotype.

Molecular and phylogenetic analysis of E. vermicularis in appendectomy specimens from Iran.

Human infection with Enterobius vermicularis occurs worldwide, particularly in children. The role of E. vermicularis in appendicitis is neglected. This study was designed to investigate genotypes of E. vermicularis detected from appendectomy specimens in the human population from Iran and clarify the intra-species variation of the parasite. Seventy appendectomies for acute clinical appendicitis isolates from Azerbaijan and North Khorasan of Iran were used in the present study. The genetic information of Tehran and Hamedan regions was also obtained from GenBank for comparison and analysis. The nucleotide sequence of cytochrome c oxidase subunit 1 (cox1) gene was analyzed to perform genetic differentiation, haplotype network analysis, and population structure. Phylogenetic analysis of all the isolates were included in type B haplogroup. The number of haplotypes in all geographical locations of Iran is not much. Network analysis of sequences for regions such as Thailand, Iran, Denmark, and Poland show three classified subtypes B1, B2, and B3 in the B haplogroup. It seems that the haplotypes of E. vermicularis detected from appendectomy are B type, and divided into three subtypes. Further research using another genetic marker is required to elucidate the genetic variation of the parasites in detail.

Absence of Asymptomatic Malaria Reservoirs in an Area with a Previous History of Local Malaria Transmission: A Successful Experience in Line with the Malaria Elimination Program in Iran.

Background: Asymptomatic malaria is a major challenge to be addressed in the implementation of the malaria elimination program. The main goal of the malaria surveillance system in the elimination phase is to identify reliably all the positive cases of malaria reliably (symptomatic and asymptomatic) in the shortest possible time. This study focused on the monitoring of asymptomatic malaria reservoirs in areas where local transmission had been previously established. Methods: It was a case-study approach that was conducted in the Anarestan area. A total of 246 residents and immigrants living in the area at the age range of 4-60 years old were randomly selected to be tested for malaria by microscope, RDT, and nested-PCR techniques. The inclusion criterion for participants to be entered into the study was the absence of specific symptoms of malaria. Moreover, participants who have been taking antimalarials for the last month were excluded from the study. Results: The results indicated no positive cases of asymptomatic malaria among the participants tested by all methods. Conclusion: The results of this study have shown that, without concerns for asymptomatic parasitic patients, a malaria elimination program has been successfully implemented within the studies area. In addition, the findings emphasized the existence of a strong malaria surveillance system in this area.

Genetic Diversity of Toxoplasma gondii by Serological and Molecular Analyzes in Different Sheep and Goat Tissues in Northeastern Iran.

Background: Toxoplasmosis is a parasitic disease caused by compilation protozoan agent Toxoplasma gondii, leading to significant financial and quality-adjusted life-year losses. Overcooked or raw meat consumption has been a considerable transmission route. The present study was conducted to determine the seropositivity rate of T. gondii in sheep and goats by serological and molecular tests and genotyping of obtained isolates in northeast Iran. Methods: Blood and tissue samples (diaphragm, heart) of 296 animals (including 168 sheep and 128 goats) were collected from the slaughterhouse in Quchan Country from august 2016 to April 2017. Modified agglutination test (MAT) and the PCR method performed to detect parasite DNA on tissues.PCR-RFLP method of GRA6 gene was used to determine the genotype of T. gondii. In addition, sequencing analysis was performed to evaluate the Toxoplasma type strains. Results: Serum positive for MAT results were found in 27.4% of sheep and 23.4% of goats. Positive PCR of B1 gene results in diaphragm and heart tissues of sheep and goats was 47.8% and 26.1%, 40% and 23.3%, respectively. PCR of GRA6 gene results were positive in 10 samples that RFLP technique results using MseI enzyme revealed genotype I. Sequencing and phylogenetic analysis revealed DNA of all samples was closely related to Toxoplasma type I. Conclusion: Concerning the high seropositivity rate of toxoplasmosis, undertaking an appropriate preventive program for reducing the prevalence of T. gondii infection by raw or undercooked meat consumption of livestock is recommended. Our study supports the notion that these animals' consumption of raw and undercooked meat can be a probable source of human toxoplasmosis.

Molecular and serological evaluation of visceral leishmaniasis in domestic dogs and cats in Maragheh County, north-west of Iran, 2018-2021.

OBJECTIVE: Zoonotic visceral leishmaniasis (VL) is caused by Leishmania infantum, of which dogs are the main reservoir. VL is endemic in the Middle East, also in some parts of Iran. Following reports of new cases of VL in children in Maragheh County, the non-endemic area of the disease, we encouraged to conduct a preliminary study on domestic dogs and cats to identify their potential role as reservoirs for the disease. MATERIALS AND METHODS: This study was conducted during a period of 3 years from 2018 to 2021. Two hundred ownership dogs and 25 cats from Maragheh County, north-west of Iran, were randomly screened. Blood samples were collected. A direct agglutination test (DAT) was used for the detection of anti-L. infantum antibodies. Furthermore, buffy coat samples from the L. infantum seropositive animals were examined to detect parasite presence using polymerase chain reaction. RESULTS: Out of the total of 200 ownership dogs evaluated, 170 (85%) were male and 30 (15%) were female with a mean age of 4.3 years. Anti-L. infantum antibodies (IgG cut-off ≥ 1:320) were observed in 3.5% of dogs (7/200) by the DAT test. All seropositive dogs were identified in the first year of examination. Regarding molecular approaches in seropositive dogs, two samples were positive for a 565 bp kDNA minicircle gene specific for L. infantum. During the study period, no seropositive case was detected in the cats examined. CONCLUSIONS: This study shows that the domestic cycle of L. infantum has been established in the studied region. It is necessary to increase the awareness and monitoring of the disease with the study of wild reservoirs periodically.

Three cases of brain hydatidosis in North Khorasan, Iran.

Cystic hydatidosis is a serious public health problem in Iran. Although cysts can develop in almost all organs and the brain cysts are very rare. Here, we present 3 confirmed cases of brain hydatidosis and the patients who underwent successful surgery. Pathological examinations demonstrated the presence of cystic hydatidosis.

Spatio-temporal variability of malaria infection in Chahbahar County, Iran: association with the ENSO and rainfall variability.

Malaria is one of the most widespread communicable diseases in the southeast regions of Iran, particularly the Chabahar County. Although the outbreak of this disease is a climate-related phenomenon, a comprehensive analysis of the malaria-climate relationship has not yet been investigated in Iran. The aims of this study are as follows: a) analyzing the seasonal characteristics of the various species of the infection; b) differentiating between number of patients during El Niño and La Niña and also during the wet and dry years. The monthly malaria statistics collected from twelve health centers were firstly averaged into seasonal scale and then composited with the corresponding data of the ground-based meteorological records, Southern Oscillation Index (SOI), and the satellite-based rainfall data. The proper statistical tests were used to detect differences in the number of patients between El Niño and La Niña and also between the adopted wet and dry episodes. Infection rate from the highest to the lowest was associated with summer, autumn, spring, and winter, respectively. Plasmodium falciparum, P. vivax, and the other species were responsible for 22%, 75%, and 3% of the sickness, respectively. The outbreak of P. falciparum/P. vivax occurs during autumn/summer. Due to the malaria eradication programs in urban areas, infection statistics collected from the rural areas were found to be more climate-related than that of urban regions. For rural/urban areas, the infection statistics exhibited a significant decline/increase during El Niño episodes. In autumn, spring, and winter, the patient number has significantly increased/decreased during the dry/wet years, respectively. These relationships were, however, reversed in summer.

Immunogenic properties of empty pcDNA3 plasmid against zoonotic cutaneous leishmaniasis in mice.

BACKGROUND: Leishmania (L) parasite, the causative agent of zoonotic cutaneous leishmaniasis (ZCL), effectively stimulates the mammalian cells to mount strong humoral responses by enhancing T-helper-2 (Th2)-associated cytokines for its survival. The best strategy to decrease the intensity of infection in the host is induction of cellular immunity. METHODS: We evaluated the effects of the empty bacterial pcDNA3 plasmid on mice infected with L. major and quantified the immune mediators including IFN-γ, IL-4, IL-10, IgG2a, IgG1, arginase activity and nitric oxide (NO) in the mice. Moreover, the footpad lesion size and parasite load were assessed. RESULTS: We observed that pcDNA3 could modulate the immune responses in favor of host cells and decrease the disease severity. Th2- associated mediators, including arginase, IL-4, and IL-10 are downregulated, while cellular responses are upregulated in line with an increase in the levels of nitric oxide (NO) and interfero-gamma (IFN-γ). Interestingly, pcDNA3 induced specific Th1-associated antibodies, IgG2a isotype; however, it suppressed the production of humoral IgG1. The stimulation of the immune response by the empty pcDNA3 is able to shift the immune function to predominant cellular responses caused by Th1, and it had a positive effect on the treatment of zoonotic cutaneous leishmaniasis (ZCL). CONCLUSIONS: Altogether, we introduced the pcDNA3 as a potential interfering factor in the modulation of the immune system against ZCL. Since this vector has been widely used as a control group in different studies, we suggest that the potential function of the empty vector should be deeply assessed, as it exerts anti-parasitic effects on mice infected with L. major.

Prevalence of camel babesiosis in southeast of Iran.

Babesiosis is a globally distributed zoonotic parasitic disease in a broad range of vertebrates with great importance in the veterinary field. The standard diagnostic test for Babesiosis in animals is microscopic identification of the parasite in a venous blood smear stained with Giemsa combined with assessment of clinical manifestations throughout the acute phase of the disease. The present study was planned to determine the presence of Babesia species in camels from the southeastern regions of Iran. A total of 140 blood samples of camels were randomly collected in four selected cities including Qaen, Nehbandan, Iranshahr, and Zahedan from March to August 2019. Blood smears of each case were also examined by the Giemsa staining method and extracted DNA samples were subjected to internal transcribed spacers (ITS1) polymerase chain reaction (PCR) amplification. The prevalence rates using microscopically and molecular examinations were 10% and 19.28%, respectively. The prevalence rates significantly vary between the selected regions (p = 0.003). PCR technique showed higher sensitivity than microscopy. We found that all infected camels were positive for Babesia caballi. The rate of infection with Babesia among the camel in Zahedan is remarkable. Early diagnosis and early treatment can prevent further spread of the disease in this area.

Downregulation of barley ferulate 5-hydroxylase dramatically alters straw lignin structure without impact on mechanical properties.

Barley is a major cereal crop for temperate climates, and a diploid genetic model for polyploid wheat. Cereal straw biomass is an attractive source of feedstock for green technologies but lignin, a key determinant of feedstock recalcitrance, complicates bio-conversion processes. However, manipulating lignin content to improve the conversion process could negatively affect agronomic traits. An alternative approach is to manipulate lignin composition which influences the physical and chemical properties of straw. This study validates the function of a barley ferulate 5-hydroxylase gene and demonstrates that its downregulation using the RNA-interference approach substantially impacts lignin composition. We identified five barley genes having putative ferulate 5-hydroxylase activity. Downregulation of HvF5H1 substantially reduced the lignin syringyl/guaiacyl (S/G) ratio in straw while the lignin content, straw mechanical properties, plant growth habit, and grain characteristics all remained unaffected. Metabolic profiling revealed significant changes in the abundance of 173 features in the HvF5H1-RNAi lines. The drastic changes in the lignin polymer of transgenic lines highlight the plasticity of barley lignification processes and the associated potential for manipulating and improving lignocellulosic biomass as a feedstock for green technologies. On the other hand, our results highlight some differences between the lignin biosynthetic pathway in barley, a temperate climate grass, and the warm climate grass, rice, and underscore potential diversity in the lignin biosynthetic pathways in grasses.

Acute eosinophilic appendicitis caused by Taenia saginata: A case report.

INTRODUCTION: The role of parasites in the pathogenesis of appendicitis has been debated for a long time. To date, several gastrointestinal parasites have been reported as the causes of appendicitis in humans. Taenia infestation of the appendix is uncommon and few cases have been reported in the literature. PRESENTATION OF CASE: We reported a case of acute eosinophilic appendicitis (AEA) in a 42-year-old woman caused by T. saginata in northern Iran. The patient was admitted to the emergency department with a 2-day history of acute abdominal pain in her lower right quadrant. Abdominal ultrasonography showed intra-abdominal bleeding and endometrium cysts. Routine hematological tests showed increases in white blood cell (WBC) count of 19.8 × 103 per mcL with 3% eosinophilia. During abdominal laparotomy, peritoneal fluid was bulked with abdominal bleeding due to rupture of the uterine cyst. After investigation of inflammation in the appendix region, patient underwent appendectomy. Histopathological findings showed acute inflammation with eosinophils and a large number of round eggs with flattened segments of the genus Taenia. It is impossible to distinguish between T. saginata and T. solium based solely on egg morphology in the specimens. Therefore, based on history of the patient, which included no consumption of pork, the species was identified as T. saginata. At the three months follow-up, the patient was in good health. CONCLUSION: In the current study, a case of AEA by T. saginata was reported. However, this was not the first case of acute appendicitis by T. saginata. Further studies are necessary to show roles of parasites in pathogenesis of AEA.

Seroprevalence of Cystic Echinococcosis Using Recombinant Antigen B-ELISA in North Khorasan Province, Northeast of Iran.

BACKGROUND: Cystic echinococcosis (CE) is one of the most important helminthic parasitic diseases in Iran. The current study aimed to assess the seroprevalence of CE in North Khorasan Province, Northeast of Iran in 2018. METHODS: The study was carried out in seven cities of North Khorasan Province. Venous blood samples were collected from 932 individuals referring to health centers of those seven cities. A questionnaire was used to obtain the data regarding the subject's gender, age, residence and risk factors linked to the hydatid cyst. Sera samples were evaluated for anti-hydatid cyst antibodies in an ELISA system, using a recombinant B8/1 antigen of E. granulosus. RESULTS: Of the 932 recruited subjects, 496 (53.2%) were male and 436 (46.8%) were female. The range of participants' age was between 11 to 83 yr old and the mean age of the subjects was 35.4 (±12.7) years. Anti-hydatid cyst antibodies were detected in the sera of 37 out of 932 subjects, corresponding to a seroprevalence rate of 3.96%. From these, 20 (54.05%) were male and 17 (45.95%) were female. There were no associations between seropositivity to hydatid cyst and age, the gender of the participants, residential areas and having contact with dogs (P>0.05). CONCLUSION: CE is relatively prevalent throughout the North Khorasan Province in the Northeast of Iran. Rate of CE infection in this Province is somewhat similar to the rate of infection in other parts of the country.

The main post-translational modifications and related regulatory pathways in the malaria parasite Plasmodium falciparum: An update.

There are important challenges when investigating individual post-translational modifications (PTMs) or protein interaction network and delineating if PTMs or their changes and cross-talks are involved during infection, disease initiation or as a result of disease progression. Proteomics and in silico approaches now offer the possibility to complement each other to further understand the regulatory involvement of these modifications in parasites and infection biology. Accordingly, the current review highlights key expressed or altered proteins and PTMs are invisible switches that turn on and off the function of most of the proteins. PTMs include phosphorylation, glycosylation, ubiquitylation, palmitoylation, myristoylation, prenylation, acetylation, methylation, and epigenetic PTMs in P. falciparum which have been recently identified. But also other low-abundant or overlooked PTMs that might be important for the parasite's survival, infectivity, antigenicity, immunomodulation and pathogenesis. We here emphasize the PTMs as regulatory pathways playing major roles in the biology, pathogenicity, metabolic pathways, survival, host-parasite interactions and the life cycle of P. falciparum. Further validations and functional characterizations of such proteins might confirm the discovery of therapeutic targets and might most likely provide valuable data for the treatment of P. falciparum, the main cause of severe malaria in human.

Seroprevalence of Toxocara spp. in children (3-13 years old) in Zahedan, Southeast of Iran.

Child Toxocariasis (CT) is one of the most important helminthic parasitic diseases in Iran. The current study was aimed to determine the seroprevalence of toxocariasis in children in Zahedan, southeast of Iran. In this cross-sectional study, serum samples of 373 children aged 3-13 years old referred to health centers in Zahedan were collected randomly with criteria based on the parameters that were used in earlier studies and examined for anti-Toxocara antibody using a commercial ELISA kit. Of the 373 recruited subjects, 206 (55.2%) were male and 167 (44.8%) were female. Most of the subjects (36.5%) were in the age group 3-4 years old. Anti-Toxocara antibodies were detected in the sera of five out of 373 individuals, corresponding to a seroprevalence rate of 1.3%. A significant correlation was found between the incidence of disease and eosinophilia, a history of contact with dogs or cats, as well as the consumption of raw vegetables and drinking of contaminated water. There was no significant correlation between prevalence and gender or age. The finding of this study revealed that the prevalent CT is relatively low in Zahedan region. The rate of CT infection in the southeast of Iran was lower than the rate in other parts of Iran.

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.