Echinococcus granulosus sheep strain (G1) as the predominant genotype in definitive host (dogs) isolates in northeastern Iran.

Echinococcus granulosus sensu lato (E. granulosus s.l.) is a zoonotic parasite, causing cystic echinococcosis in humans. In the present study, prevalence and genotypes of E. granulosus s.l. was assessed in stools collected from 244 dogs including 138 stray and 106 domestic animals using high resolution melting curve (HRM) method. Initially, to detect taeniid eggs in feces, all samples were examined using the formalin-ether techniques. Genomic DNA was extracted from the positive samples and E. granulosus s.l. was differentiated from other Taeniidae parasites using SSU-rDNA gene and E. granulosus s.l. was analyzed for genotyping using HRM based on the cox1 gene. In total, 12.7% (31/244) of the samples were positive for Taeniidae eggs. In addition, among the positive samples, 77.4% (24/31) were positive for E. granulosus s.l.. In details, 11.3% (12/106) of the domestic dogs and 8.7% (12/138) of the stray dogs were positive for E. granulosus s.l.. The results of HRM analysis showed that all E. granulosus s.l. isolates were G1 strain. Findings of the present study indicated a considerable prevalence of E. granulosus G1 among dogs in the northeast of Iran and imply a serious risk of transmitting to humans and livestock.

Environmental health risk factors and cutaneous leishmaniasis (CL): A case-control study in northeastern Iran.

Background & objectives: Cutaneous leishmaniasis (CL) is one of the main causes of vector-born diseases in younger population. To evaluate the association of environmental health factors on the odds of CL incidence, a case-control study was conducted in northeastern Iran. Methods: This study was conducted within 2020-2021 based on individual and household data from a tertiary referral center. Cases were patients diagnosed with CL by PCR method; controls were selected among the patients' relatives, and information was obtained from a health registry system. Demographic and socioeconomic data of 1871 subjects, included age, sex, household information and environmental health factors. Multivariable models with environmental factors in various conditions and CL were separately fit by univariate and mixed multiple unconditional logistic regression. Results: Participants included 617 cases (mean [SD] age, 13.62[13.72] years; 58.20% male) and 1264 controls (mean [SD] age, 16.45[15.44] years; 50.40% male). Results revealed that the use of well-water sources compared to surface water is significantly associated with CL (odds ratio [OR]=0.204; 95%CI, 0.13-0.33;P<0.001). Muddy houses, ruined buildings or wastelands and stagnant water, canals and rivers near the houses were also associated with CL (OR=3.85; 95%CI, 1.66-8.89; P=.002; OR=2.47; 95%CI, 1.76-3.47; P<.001). Besides, existence of pine tree was found to be a risk factor (OR=3.25; 95%CI, 2.12-4.99; P<.001) and similarly for the use of waste collection system (OR=4.43; 95%CI, 3.32-7.51; P<.001). Interpretation & conclusion: Environmental factors related to houses were significantly associated with CL and may represent the modifiable risk factors of CL disease.

Association between water and sanitation, air and emission pollution and climate change and neurological disease distribution: A study based on GBD data.

Along with the urbanization and industrialization of countries, the prevalence of chronic diseases has increased. There is ample evidence that ambient pollution can play a major role in these diseases. This study aimed to investigate the association between neurological disorders (NDs) and their subtypes with environmental factors. In this country-level study, we used the age-standardized prevalence and incidence rate (per 100,000 populations) of NDs and its subtypes that have been taken from the Global Burden of Disease (GBD) database in 2019. We used correlation and regression analysis to assess the association between variables. Also, multivariable regression analysis was performed to identify the most important variables in NDs distribution. Age-adjusted NDs incidence rate was significantly higher in developed countries compared to developing countries (11345.25 (95% CI: 11634.88-11055.62) and 9956.37 (95% CI: 10138.66-9774.08)). Association results indicated that the impact of water and sanitation could be more effective than air pollution on NDs. The increase in water and sanitation index levels was positively correlated with NDs incidence rate and prevalence (regression coefficient (b) = 38.011 (SE = 6.50) and b = 118.84 (SE = 20.64), p < 0.001, respectively) after adjusting socio-economic and demographic factors. Furthermore, the incidence of NDs was negatively correlated with the increase in air quality (b = -16.30 (SE = 7.25), p = 0.008). Water and sanitation and their related factors are plausible factors in the distribution of NDs, which may be linked to the potential role of air and water pollution, such as heavy metals and particle matters. These results can be used by politicians and municipal service planners for future planning.

High contamination of soil with Toxocara spp. eggs in the north of Iran.

Toxocarosis is an important emerging zoonotic disease, which is caused by larvae of Toxocara canis and Toxocara cati, the most widely distributed nematode parasites of dogs and cats. The soil, where Toxocara eggs become infective, is the natural source of infection. The aim of this work was to determine the levels of soil contamination with Toxocara spp. eggs in Sari district, north of Iran, in order to estimate the risk of infection of the population living in this region. A total of 141 soil samples were collected from 12 parks, 12 primary schools and 45 backyards from three regions. Soil samples were investigated for the presence of Toxocara eggs by flotation technique using sucrose solution and examined under light microscope using 10× and 40× objective. Out of 141 soil samples, 67 (47.5%) were found to contain Toxocara spp. eggs. The contamination rate in public parks, primary schools and backyards were observed 50%, 58.3% and 33.3%, respectively. The comparison of soil contamination rate from different areas, public parks, primary schools and backyards, was statistically significant (χ2=6.00, d.f.=2 and P=0.049). The public parks, backyards and primary schools, which are main places that children play, are suitable for defecation of dogs and cats. The knowledge of the soil contamination with Toxocara eggs indicates the need to take an appropriate and effective measures to prevent the infection.

Prevalence of toxocariasis and its related risk factors in humans, dogs and cats in northeastern Iran: a population-based study.

BACKGROUND: Toxocariasis is one of the most common zoonotic infections in dogs and cats. The objectives of this study were to determine the prevalence of anti-Toxocara antibodies and identify the epidemiological and clinical features and related risk factors of toxocariasis in the general population along with the prevalence of this infection in dogs and cats in northeast Iran. METHODS: In this cross-sectional study, anti-Toxocara antibodies from 1150 urban and rural participants were examined using a commercial enzyme-linked immunosorbent assay. In addition, the stool specimens of 538 dogs and 236 cats were tested using the formalin-ether concentration technique. Sociodemographic data and related risk factors were collected using a structured questionnaire and the data on clinical manifestations were obtained from personal health records. RESULTS: Anti-Toxocara antibodies were detected in 7.2% (83/1150) of the study population. Risk factors for seropositivity based on multivariable analysis were younger age (p=0.019), living in rural areas (p=0.048), occupations with high exposure risk to toxocariasis (p=0.001), contact with dogs or cats (p=0.003), contact with soil (p=0.001), history of geophagy (p=0.001) and the consumption of raw or undercooked liver (p=0.001). The prevalence of symptoms such as asthma, shortness of breath, blurred vision, abdominal pain and epilepsy were significantly higher in seropositive individuals compared with seronegative ones. Toxocara eggs were found in 15.1% (81/538) of dogs and 34.7% (82/236) of cats. A significant relationship was found between infection in dogs and cats and age, type, place of residence and anthelmintic consumption. CONCLUSIONS: Identification of anti-Toxocara antibodies in the general population and the presence of confirmed infections in dogs and cats indicates exposure to Toxocara infection as a public health problem in northeast Iran.

Cryptosporidiosis in Iranian Farm Workers and Their Household Members: A Hypothesis about Possible Zoonotic Transmission.

Objectives. The prevalence of Cryptosporidium and the risk factors of zoonotic transmission in Najafabad, Isfahan, Iran dairy farms were examined. Methods. One fecal sample was collected from all calves less than 6 months old in eight dairy farms around Najafabad (Isfahan province, Central Iran) as well as individuals working in these farms and their household members. A two-step nested PCR protocol was used to amplify the 18S rRNA gene (830 bp). Results. Cryptosporidium was identified in the stool of 36 (prevalence 8.5%) of 96 farm workers and 326 household members. Furthermore, 31 (14.2%) of 218 calf samples were positive. Cryptosporidium parvum was identified in 15 (72%) of the positive farm workers and 10 (65%) of the positive household members. Of the positive calves, 20 (64.5%) were infected with C. parvum, indicating possible zoonotic transmission in these farms. Contact with calves (P < 0.0001) was the most significant risk factor of C. parvum infection. A considerable negative association was observed between C. parvum infection and cleaning of shoes/boots after daily work (P = 0.004), hand washing (P = 0.013), and use of piped water (P < 0.006). In the multivariate analysis with logistic regression, only contact with calves was significant. Conclusion. Zoonotic transmission of C. parvum due to contact with calves is predominant among farm workers and their household members of this region and appropriate health measures must be applied to control the infection and decrease of zoonotic transmission of this parasite.

Prevalence, molecular characteristics and risk factors for cryptosporidiosis among Iranian immunocompromised patients.

Cryptosporidium spp. is a major cause of diarrhea in developing countries, mainly affecting people with compromised immune systems in general and HIV-infected individuals with low CD4 + T-cell counts in particular. This infection is self-limiting in healthy persons; however, it can be severe, progressive and persistent in those who are immunocompromised. There are few published studies concerning cryptosporidiosis and Cryptosporidium genotypes in Iranian immunocompromised patients and none of them describe risk factors. This study was undertaken to identify prevalence, genotypes and risk factors for cryptosporidiosis in immunocompromised patients. Three fecal samples were obtained at two day intervals from each of the 183 patients and processed with modified Ziehl-Neelsen staining methods and 18S rRNA gene amplification and sequencing. The overall infection prevalence was 6%. Cryptosporidium parvum was identified in isolates from five HIV-infected patients, one patient who had undergone bone marrow transplantation and one with chronic lymphocytic leukemia. Cryptosporidium hominis was identified in isolates from two HIV-infected patients and two patients with acute lymphocytic leukemia. According to univariate analysis, the statistically significant factors were diarrhea (OR = 21.7, CI = 2.83-78.4, P= 0.003), CD4 + lymphocytes less than 100 cells/mm(3) (OR = 41.3, CI = 13.45-114.8, P < 0.0001), other microbial infections (OR = 7.1321.7, CI = 1.97-25.73, P = 0.006), weight loss (OR = 73.78, CI = 15.5-350, P < 0.0001), abdominal pain (OR = 10.29, CI = 2.81-37.74.4, P= 0.001), dehydration (OR = 72.1, CI = 17.6-341.5, P < 0.0001), vomiting (OR = 4.87, CI = 1.4-16.9, P= 0.015), nausea (OR = 9.4, CI = 2.38-37.2, P < 0.001), highly active antiretroviral therapy (OR = 0.089, CI = 0.01-0.8, P= 0.015) and diarrhea in household members (OR = 7.37, CI = 2.04-26.66, P= 0.001). After multivariate analysis and a backward deletion process, only < 100 CD4 + T-lymphocytes/mm(3) maintained a significant association with infection. The authors recommend that this infection should be suspected in patients with diarrhea, weight loss and dehydration in general and in diarrheal individuals with < 100 CD4 + T-lymphocytes/mm(3).