Seroprevalence and Potential Risk Factors of Toxocariasis among General Population in Southwest Iran: Implications on the One Health Approach.

Toxocariasis is one of the most common zoonotic diseases distributed worldwide. This study aimed to estimate the seroprevalence of anti-Toxocara immunoglobulin G (IgG) antibodies and the associated risk factors among general populations living in urban and rural areas of Abadan and Khorramshahr cities in Khuzestan Province, Southwest Iran. This cross-sectional study was conducted between March and September 2022. There were 363 participants (190 females and 173 males) aged from <20 to ≥60 years old. Anti-Toxocara IgG antibodies in serum samples were measured using a commercially available enzyme-linked immunosorbent assay (ELISA). A structured questionnaire was employed to collect information regarding sociodemographic status and probable risk factors associated with toxocariasis. It was found that the seroprevalence rate in males (15.0%, 95% CI = 10.47-21.11) was higher than in females (10.5%, 95% CI = 6.92-15.70). Moreover, we observed that the seroprevalence was higher in participants at younger ages compared to other age ranges (COR = 2.55, 95% CI = 0.92-7.12, p =0.073). The findings of the univariate analysis revealed that residency in rural areas (p < 0.001), using unpurified water (p < 0.001), contact with dog (p =0.002), contact with soil (p < 0.001), consumption of improperly washed vegetables (p < 0.001), and history of drinking untreated water (p < 0.001) were risk factors associated with toxocariasis. Further comprehensive studies with a focus on humans and animals should be designed in different areas of the Province. The data represented by the current study are useful to health policymakers to consider precise surveillance and effective prevention measures to control this zoonotic infection among general populations.

Seroprevalence and risk factors of Toxocara canis infection in children aged 2-15 years from the southwest Iran.

Human toxocariasis (HT) is one of the most prevalent zoonotic diseases with a worldwide distribution. There is no epidemiological study showing the seroprevalence of toxocariasis among children in southwest Iran, Khuzestan Province. Accordingly, this study was designed to estimate the seroprevalence of Toxocara canis (T. canis) IgG antibodies in children (2-15 years old) and assess the main risk factors associated to human infection. In this cross-sectional study, a total of 259 children were invited to participate from the southwest Iran (Abadan and Khorramshahr cities, Khuzestan Province) between April to August 2021. Serum anti-T. canis IgG antibodies were measured using a commercially available enzyme-linked immunosorbent assay (ELISA). A structured questionnaire was also employed to collect some socio-demographic information and probable risk factors associated to T. canis infection. The overall seroprevalence rate of T. canis in children was 7.3% (95% CI = 4.75 - 11.17%). The univariate analysis demonstrated that living in rural communities (P < 0.001), drinking unpurified water (P < 0.001), contact with cat (P = 0.033), consumption of improperly washed vegetables (P = 0.002), and history of drinking water from unsafe sources (P = 0.003) were risk factors associated with T. canis seroprevalence in children. However, after adjusting for confounders, multivariable logistic regression analysis verified that only drinking unpurified water (P = 0.016) remained a significant risk factor. In addition, both univariate (P = 0.032) and multivariate logistic regression analysis (P = 0.037) revealed that seropositivity of T. canis infection was significantly associated with asthma. The current report provides beneficial baseline epidemiological findings regarding the seroprevalence of T. canis in children as a vulnerable group for this infection. This data can be used by health policy makers to plan effective prevention programs and control this neglected infection among high risk subjects.

Immunoinformatic Analysis of Calcium-Dependent Protein Kinase 7 (CDPK7) Showed Potential Targets for Toxoplasma gondii Vaccine.

Apicomplexan parasites, including Toxoplasma gondii (T. gondii), express different types of calcium-dependent protein kinases (CDPKs), which perform a variety of functions, including attacking and exiting the host cells. In the current bioinformatics study, we have used several web servers to predict the basic features and specifications of the CDPK7 protein. The findings showed that CDPK7 protein has 2133 amino acid residues with an average molecular weight (MW) of 219085.79 D. The aliphatic index with 68.78 and grand average of hydropathicity (GRAVY) with -0.331 score were estimated. The outcomes of current research showed that the CDPK7 protein included 502 alpha-helix, 1311 random coils, and 320 extended strands with GOR4 method. Considering the Ramachandran plot, the favored region contains more than 92% of the amino acid residues. In addition, evaluation of antigenicity and allergenicity showed that CDPK7 protein has immunogenic and nonallergenic nature. The present research provides key data for more animal-model study on the CDPK7 protein to design an efficient vaccine against toxoplasmosis in the future.

The Probable Association between Chronic Toxoplasma gondii Infection and Type 1 and Type 2 Diabetes Mellitus: A Case-Control Study.

PURPOSE: The probable association between Toxoplasma gondii (T. gondii) infection and diabetes mellitus (DM) is still controversial, and there are several studies with conflicting results. Thus, this study was performed to assess the possible association between chronic T. gondii infection and type 1 diabetes mellitus (T1DM) and T2DM. METHODS: In this case-control study, a total of 105 diabetic subjects including 36 patients with T1DM and 69 patients with T2DM were recruited. In addition, 150 nondiabetic subjects were enrolled as controls. Each case group had its own control group. Each participant completed a structured questionnaire obtaining demographic information. Serum samples were examined for T. gondii-specific IgG antibody using enzyme-linked immunosorbent assay (ELISA) method. RESULTS: Analysis revealed that 69.4% and 34.0% of patients with T1DM and control subjects were serologically positive for T. gondii, respectively (odds ratio (OR): 4.41; 95% confidence interval (CI): 1.75-11.06; P=0.001). Moreover, 72.5% of T2DM patients and 29.0% of healthy individuals were seropositive for T. gondii (OR: 6.44; 95% CI: 3.25-12.74; P < 0.001). Among risk factors, only contact with cats was significantly associated with IgG seroprevalence in both T2DM patients (P < 0.001) and control subjects (P=0.045). CONCLUSION: Although the results showed that chronic T. gondii infection is significantly associated with T1DM and T2DM, there remain many questions regarding the exact mechanisms of T. gondii in the pathogenesis of DM.

Detection of Anti-Toxoplasma gondii IgG and IgM Antibodies and Associated Risk Factors during Pregnancy in Southwest Iran.

Background: This research was aimed at evaluating the seroprevalence of acute and chronic Toxoplasma gondii (T. gondii) infection in pregnant women and related risk factors in southwest Iran. Methods: In this cross-sectional study, eighty-eight pregnant women were included from October 2019 to December 2019. The presence of anti-T. gondii IgM and IgG antibodies was measured using the enzyme-linked immunosorbent assay (ELISA). In addition, a questionnaire consisting of demographic information was completed for each subject. Results: The overall seroprevalence of T. gondii infection was estimated to be 34.09% (30/88). Of these, 1 (1.13%) and 29 (32.95%) samples were found positive for IgM and IgG, respectively. Regarding the risk factors, the consumption of raw/undercooked meat (P value = 0.007) and history of abortion (P value = 0.017) were significantly associated with IgG seroprevalence in pregnant women. Conclusion: The results showed that the pregnant women of southwest Iran might be moderately exposed to T. gondii. Since the risk of acute T. gondii infection in this susceptible group is very important, regular screening tests to diagnose the infection are recommended before pregnancy.

Bioinformatics analysis of calcium-dependent protein kinase 4 (CDPK4) as Toxoplasma gondii vaccine target.

OBJECTIVES: Toxoplasma gondii (T. gondii), an obligate intracellular apicomplexan parasite, could affect numerous warm-blooded animals, such as humans. Calcium-dependent protein kinases (CDPKs) are essential Ca2+ signaling mediators and participate in parasite host cell egress, outer membrane motility, invasion, and cell division. RESULTS: Several bioinformatics online servers were employed to analyze and predict the important properties of CDPK4 protein. The findings revealed that CDPK4 peptide has 1158 amino acid residues with average molecular weight (MW) of 126.331 KDa. The aliphatic index and GRAVY for this protein were estimated at 66.82 and - 0.650, respectively. The findings revealed that the CDPK4 protein comprised 30.14% and 34.97% alpha-helix, 59.84% and 53.54% random coils, and 10.02% and 11.49% extended strand with SOPMA and GOR4 tools, respectively. Ramachandran plot output showed 87.87%, 8.40%, and 3.73% of amino acid residues in the favored, allowed, and outlier regions, respectively. Also, several potential B and T-cell epitopes were predicted for CDPK4 protein through different bioinformatics tools. Also, antigenicity and allergenicity evaluation demonstrated that this protein has immunogenic and non-allergenic nature. This paper presents a basis for further studies, thereby provides a fundamental basis for the development of an effective vaccine against T. gondii infection.

Low Serum Levels of Selenium, Zinc, Iron, and Zinc/Copper Ratio in an Endemic Region of Cutaneous Leishmaniasis in Southwest Iran.

Leishmaniasis is a widespread tropical infection; cutaneous leishmaniasis (CL) is the most common form of this disease known to cause significant morbidity. Trace metals, including selenium, zinc, iron, and copper, are required for the activity of several enzymes involved in immune system responses. The aim of this research was to measure the serum levels of selenium (Se), zinc (Zn), copper (Cu), iron (Fe), and Zn/Cu ratio in patients with CL. In this case-control study, 80 patients with CL and 80 healthy volunteers (not exposed to CL) from a CL endemic region in southwest Iran agreed to participate. Both clinical and parasitological verifications were made to include each subject as a CL-positive case. A questionnaire was completed for each participant which included the following criteria: age (year), height (cm), weight (kg), body mass index (kg/m2), and duration of disease (day). The biochemical assays were performed according to the standard protocols, and the values of Zn, Cu, Se, and Fe were expressed in micrograms per deciliter (µg/dl). All results were expressed as mean ± standard deviation (SD), and the statistical significance level was defined to be less than 0.05 (P < 0.05). There were no statistically significant differences in terms of mean values of age, body weight, height, and body mass index between CL patients and the control group (P > 0.05). The mean ± SD concentrations of Zn, Fe, and Se in the control group were found to be 118.87 ± 6.35 µg/dl, 123.00 ± 8.40 µg/dl, and 11.26 ± 1.88 µg/dl, respectively. These trace elements (TEs) were statistically lower (P < 0.001) in patients with CL (case group) with values of 83.05 ± 7.32 µg/dl for Zn, 86.51 ± 10.09 µg/dl for Fe, and 3.83 ± 1.20 µg/dl for Se. We have also observed that serum levels of Cu in CL-positive group were significantly higher than in the controls (P < 0.001). Furthermore, CL patients had significantly lower Zn/Cu ratio than controls (0.63 ± 0.05 µg/dl vs. 1.11 ± 0.10; P < 0.001). The alternation in serum levels of TEs may be a part of the defense strategy of the organism. Based on these results, it can be suggested that serum levels of these TEs can be a useful marker to estimate the prognosis of CL infection.

Seroprevalence and associated risk factors of Toxoplasma gondii infection in patients undergoing hemodialysis and healthy group.

OBJECTIVES: In this study, the seroprevalence of anti-Toxoplasma gondii (T. gondii) specific antibodies in patients undergoing hemodialysis compared to the control group were evaluated. In this case-control study, 200 hemodialysis patients (HDP) and 100 healthy controls were participated. The specific antibodies (IgG/IgM) in both groups were tested using enzyme-linked immunosorbent assay (ELISA) method. A structured questionnaire containing some demographic information was completed for each person in case and control groups. RESULTS: The overall seroprevalence of T. gondii infection was 49.5% (99/200) and 23.0% (23/100) in the case and control groups, respectively. There was a significant association between seroprevalence of T. gondii infection and contact with cats (P < 0.001), consumption of raw/undercooked meat (P = 0.01), and source of drinking water (P = 0.001) in the hemodialysis patients. Also, in the control subjects, there were a significant association between consumption of raw/undercooked meat (P = 0.04) and source of drinking water (P = 0.001) with T. gondii infection. The findings showed a high seroprevalence of T. gondii infection in HDP compared with healthy controls; thus, we recommend the regular screening programs for T. gondii infection in this susceptible group.

In-depth computational analysis of calcium-dependent protein kinase 3 of Toxoplasma gondii provides promising targets for vaccination.

PURPOSE: The Toxoplasma gondii calcium-dependent protein kinase-3 (CDPK3) is a key enzyme for parasite egress, control of calcium-dependent permeabilization in parasitophorous vacuole membrane and tissue cyst formation. In this study, we comprehensively explored the bioinformatics features of this protein to improve vaccine design against T. gondii. MATERIALS AND METHODS: Various web servers were employed for the analysis of physico-chemical properties, post-translational modifications, localization in the subcellular milieu, secondary and tertiary structures, as well as B-cell, major histocompatibility complex (MHC)-binding and cytotoxic T-lymphocyte (CTL) epitopes. RESULTS: This protein was a 537 amino acid antigenic and non-allergenic molecule with a molecular weight of 60.42 kDa, a grand average of hydropathicity score of -0.508, and aliphatic index of 79.50. There exists 46.74% alpha helix, 12.48% extended strand, and 40.78% random coil in the secondary structure. Ramachandran plot of the refined model demonstrated 99.3%, 0.7%, and 0.0% of residues in the favored, allowed and outlier areas, respectively. Besides, various potential B-cell (continuous and conformational), MHC-binding and CTL epitopes were predicted for Toxoplasma CDPK3 protein. CONCLUSION: This article provides a foundation for further investigations, and laid a theoretical basis for the development of an appropriate vaccine against T. gondii infection.

Prevalence of Intestinal Parasitic Infections in the Southwest of Iran: A Four-year Retrospective Study.

BACKGROUND: The current study was aimed to assess the prevalence of intestinal parasitic infections (IPIs) in persons who were referred to selected hospitals of Abadan and Khorramshahr cities, in the southwest of Iran. MATERIALS AND METHODS: In this descriptive cross-sectional study, 43200 and 28821 stool specimens were gathered from Abadan and Khorramshahr cities, respectively, during four consecutive years (2014-2017). RESULTS: A decreasing trend was seen in the prevalence rate of IPIs in Abadan and Khorramshahr cities. The overall prevalence of IPIs was estimated to be 5.82% and 6.11% in Abadan and Khorramshahr cities, respectively. In Abadan city, the proportion of IPIs in male persons with 56% was higher than females 44%, while in Khorramshahr city, more prevalence was observed in females (54% vs. 46%). Moreover, according to the season, the highest prevalence was recorded in Spring (30.4%) and Summer (31.1%) in Abadan and Khorramshahr cities, respectively. We found Giardia lamblia, as the most frequent parasite in studied individuals of both cities (Abadan: 2.92%; 1261/43200 and Khorramshahr: 3.15%; 908/28821). Other parasites were as follows: Entamoeba histolytica/dispar, E. coli, E. hartmanni, Blastocystis hominis, Hymenolepis nana, Enterobius vermicularis, Strongyloides stercoralis, and Taenia spp. CONCLUSION: This was the first study on the prevalence of IPIs in Abadan and Khorramshahr cities, southwest of Iran. Intestinal parasites are still the main public health concern in these regions. Health education, improving sanitary conditions, screening and treatment of infected people, particularly in rural and semi-urban areas can be helpful.

Evaluation of Antileishmanial Activity Employing Conventional and Solid Lipid Nanoparticles of Amphotericin B on Leishmania major In Vitro and In Vivo.

BACKGROUND: Obligate intracellular parasites of Leishmania genus belong to the family Trypanosomatidae and more than twenty species cause this neglected vector-borne infection throughout the globe. OBJECTIVE: The current study was aimed to assess the antileishmanial activity of Amphotericin B (AmB) and AmB formulated into solid lipid nanoparticles (SLNs) in vitro and in vivo. MATERIALS AND METHODS: In the present research, microemulsification and high shear homogenization methods were used to prepare SLNs. Leishmania major (L. major) promastigotes were cultured in RPMI 1640 and incubated for three time points of 24, 48 and 72 h at 25±1°C. Then, the MTT colorimetric assay was employed for obtaining 50% inhibitory concentration (IC50). Finally, the efficacy of AmB and AmB-SLN was evaluated for the treatment of experimental cutaneous leishmaniasis (CL) in BALB/c mice. RESULTS: The average diameter sizes of prepared AmB-SLN were <180 nm and monodisperse preparations with polydispersity index 0.21±0.29. The antileishmanial activity of AmB and AmBSLN revealed a dose and time-dependent manner in vitro. The IC50 values of AmB (38.18±1.33, 25.06±2.00, and 13.87±0.61 µg/ml) and AmB-SLN (0.40±0.02, 0.26±0.02, and 0.14±0.01 µg/ml) were estimated after 24, 48 and 72 hours, respectively. In all BALB/c treatment groups, the diameter of lesions was significantly smaller than the control group. CONCLUSION: AmB-SLN was significantly more potent than AmB in vitro and in vivo. The discovery of new effective drugs based on nanocarriers, such as SLN, is practical and opens a new window for the treatment of CL.

Cutaneous leishmaniasis: an epidemiological study in southwest of Iran.

The current study was aimed to evaluate the frequency and epidemiological aspects of cutaneous leishmaniasis (CL) in the southwest of Iran, an endemic focus for the leishmaniasis from 2014 to 2017. In the present retrospective cross-sectional study, all suspicious CL persons who were referred to health centers affiliated to Abadan School of Medical Sciences (Abadan and Khorramshahr cities) were tested. In this regard, both clinical and parasitological (staining with Giemsa) verifications were performed to diagnose a case. Furthermore, a structured questionnaire containing some demographic details was applied for each positive patient. In total, 151 and 132 positive CL cases were identified in Abadan and Khorramshahr cities, respectively. More frequency of CL was observed during the Winter season, among male subjects, and in urban inhabitants in both cities. The incidence of CL based on age distribution was higher in the age range of 20-30 years than others. Besides, the hands and feet were the most involved organs. Although the frequency of CL has declined in the region, CL is still a public health problem. More appropriate control strategies are required to limit and eliminate the infection in the future.

Rhomboid antigens are promising targets in the vaccine development against Toxoplasma gondii.

Toxoplasma gondii (T. gondii) is an obligate intracellular parasite with worldwide distribution. It is estimated that near one-third of the people around the globe are latently seropositive for the parasite. Since the current common drugs are incapable in the elimination of parasites within tissue cysts, the development of an effective vaccine has high priority for researchers to limit the infection. During recent years, non-stop efforts of scientists have made great progress in the identification and development of T. gondii candidate vaccines. However, there is a lack of a commercially licensed vaccine for human application yet. Rhomboid proteases (ROMs) are a class of serine proteases that have an important role in the invasion of the parasites that can be considered as a new target for vaccine strategy. They also play critical roles in mitochondrial fusion and growth factor signaling, allowing the parasite to completely enter into the host cell. In the current review, we have summarized the recent progress regarding the development of ROM-based vaccines against acute and chronic T. gondii infection in animal models.

Seroepidemiological evaluation of Toxoplasma gondii immunity among the general population in southwest of Iran.

Toxoplasmosis is a cosmopolitan zoonotic infection, caused by a unicellular protozoan parasite known as Toxoplasma gondii (T. gondii) that belongs to the phylum Apicomplexa. The present investigation was aimed to evaluate the seroprevalence of T. gondii infection in the general population of Abadan city. In this cross-sectional study, a total of 496 subjects were participated. Anti-T. gondii IgG and IgM antibodies were tested using commercially available enzyme-linked immunosorbent assay (ELISA). Moreover, a structured questionnaire was completed for each person. Out of 496 subjects, 188 (37.9%) and 30 (6.05%) samples were seropositive for IgG and IgM, respectively. The more seroprevalence was found during spring season, among female subjects, in rural inhabitants, in persons with the education level of diploma or lower, from the subjects with a history of contact with cat, in individuals who consumed raw/undercooked meat, and amongst who drink unpurified water. The results showed that inhabitants of tropical areas, may be moderately exposed to T. gondii. Increase of knowledge of people about toxoplasmosis, certainly affects in reduction of the infection.

Basic Occupational Health Services for Agricultural Workers in the South of Iran.

The agricultural sector has by far the world's largest labour force, there are more than one billion workers in this industry worldwide, which contains half of the total world labour force. On the other hand, agriculture is one of the most hazardous occupations, and many workers suffer occupational accidents and ill health each year. Farming and animal breeding are associated with exposure to a wide variety of risk factors, including zoonotic agents, dust, elements of the thermal environment, noise, vibration and chemicals. Although half of the world's population are economically active and spend at least one third of their time in the workplace, only 15% of the workers have access to basic occupational health services. According to a WHO report, Iran has a well-structured health care system through which basic health care services are available to the entire population, and health indicators in Iran have consistently improved. The agricultural health program in Iran is being carried out in the cities and rural areas, and occupational health services are mainly integrated into the health network. This paper aims to describe the health care system and basic occupational health services (BOHs) available to 5,300 agricultural enterprises with 8,380 employees in the cities of Abadan, Khorramshahr and Shadegan in the Abadan region (Abadan, Khoramshahr and Shadegan districts), in the south of Iran.

Molecular diagnosis of potentially human pathogenic Enterocytozoon bieneusi and Encephalitozoon species in exotic birds in Southwestern Iran.

Microsporidia are obligate intracellular parasites that produce spores. The infections caused by these parasites are mostly considered to be opportunistic in immunodeficient patients. Because of the zoonotic nature of microsporidia as well as the increasing prevalence of immunodeficiency diseases, the aim of this study was to evaluate the molecular diagnosis of Enterocytozoon bieneusi (E. bieneusi) and Encephalitozoon spp. in exotic birds in southwestern Iran. Initially, 816 stool specimens were collected and stained by modified trichrome (Weber) staining. The slides were explored using light microscopy. In the next stage, the extracted DNA was amplified using a multiplex/nested PCR method. RFLP with the Mnl1 restriction enzyme was used to differentiate the Encephalitozoon species in the products of the molecular analysis. Out of 816 samples, 138 and 181 cases were found to be positive by the staining and the multiplex/nested-PCR methods, respectively. Of the 181 samples, 103 and 78 samples were positive for E. bieneusi and Encephalitozoon spp., respectively. The Encephalitozoon species were 17 E. cuniculi, 52 E. intestinalis and 9 E. hellem. Of 103 E. bieneusi samples, 57, 39, 2 and 5 cases were detected as genotypes D, M, E and L, respectively. The results showed a relatively high prevalence of microsporidia in exotic birds, and according to the results of the genotyping, these birds can be an important source of microsporidiosis. It is essential that high-risk individuals, including patients with immunodeficiency diseases, receive accurate and valid information about the risk of direct and indirect contact with infected exotic birds.

Distribution of haematological indices among subjects with Blastocystis hominis infection compared to controls.

INTRODUCTION: Some studies suggest Blastocystis hominis is a potentially pathogenic protozoa. Blastocystis hominis contributed to anaemia in children aged 8-10 years old in one study. AIM: To compare haematological indices in cases with blastocystis hominis infection with healthy controls. MATERIAL AND METHODS: From 2001 to 2012, 97600 stool examinations were done in 4 university hospitals. Parasites were observed in 46,200 specimens. Of these cases, subjects with complete laboratory investigation (complete blood count - CBC, ferritin, total iron binding capacity - TIBC, and serum) and blastocystis hominis infection were included in this study as the case group. Of these cases, 6851 cases had only B. hominis infection. In the control group, 3615 subjects without parasite infestation were included. Age, haemoglobin (Hb), serum iron, TIBC, white blood cell (WBC), platelet (PLT), mean corpuscular volume (MCV), haematocrit (HCT) and erythrocyte sedimentation rate (ESR) were recorded for cases and controls. SPSS software version 13.0 was used for analysis. Independent sample t-test and χ(2) tests were used for comparison. RESULTS: Erythrocyte sedimentation rate level was significantly higher in cases with B. hominis infection (p < 0.05). C-reactive protein level was positive in 1.46% of cases and 0.5% of controls, which was statistically significant (p < 0.05). Frequency of serum iron < 120 was significantly higher in cases with B. hominis infection compared to controls. Occult blood was positive in 0.93% of cases and in none of the controls (p < 0.05). CONCLUSIONS: The ESR, CRP and occult blood was significantly higher in cases with B. hominis infection.