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Objective: To determine the potential effect of environment variables on cutaneous leishmaniasis occurrence using time-series models and compare the predictive ability of seasonal autoregressive integrated moving average (SARIMA) models and Markov switching model (MSM). Methods: This descriptive study employed yearly and monthly data of 49 364 parasitologically-confirmed cases of cutaneous leishmaniasis in Isfahan province, located in the center of Iran from January 2000 to December 2019. The data were provided by the leishmaniasis national surveillance system, the meteorological organization of Isfahan province, and Iranian Space Agency for vegetation information. The SARIMA and MSM models were implemented to examine the environmental factors of cutaneous leishmaniasis epidemics. Results: The minimum relative humidity, maximum relative humidity, minimum wind speed, and maximum wind speed were significantly associated with cutaneous leishmaniasis epidemics in different lags (P<0.05). Comparing SARIMA and MSM, Akaikes information criterion (AIC), and mean absolute percentage error (MAPE) in MSM were much smaller than SARIMA models (MSM: AIC=0.95, MAPE=3.5%; SARIMA: AIC=158.93, MAPE:11.45%). Conclusions: SARIMA and MSM can be a useful tool for predicting cutaneous leishmaniasis in Isfahan province. Since cutaneous leishmaniasis falls into one of two states of epidemic and non-epidemic, the use of MSM (dynamic) is recommended, which can provide more information compared to models that use a single distribution for all observations (Box-Jenkins SARIMA model).
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Objective: To review the prevalence of cryptosporidiosis among animal population of Iran. Methods: Data were systematically gathered from 1 January 2000 to 1 January 2020 in the Islamic Republic of Iran from the following electronic databases: PubMed, Springer, Google Scholar, Science Direct, Scopus, Web of Science, Magiran, and Scientific Information Database (SID). According to the preferred reporting items for systematic reviews and meta-analyses (PRISMA) and inclusion criteria, 88 eligible studies were obtained. Results: The pooled prevalence of cryptosporidiosis using random and fixed effects model according to heterogeneity among animals was as follows: rodents 18.8% (95% CI 12.6%-25.0%), camels 17.1% (95% CI 8.6%-25.7%), cattle 16.8% (95% CI 13.4%-20.1%), goats 14.1% (95% CI 5.2%-23.0%), horses 12.2% (95% CI 8.3%- 16.2%), birds 10.5% (95% CI 7.6%-13.4%), sheep 9.9% (95% CI 2.4%-4.9%), cats 8.8% (95% CI 4.8%-12.8%) and dogs 3.7% (95% CI 7.0%-12.8%). Conclusions: Cryptosporidiosis has been reported and present in a wide range of animals in Iran over the years and has a high prevalence in most of these species.
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Objective: To delineate the H9N2 influenza virus circulation within Iran and its neighboring countries, the potential source of the epidemic in these countries, and its date of origin. Methods: We obtained all hemagglutinin (HA) and neuraminidase (NA) nucleotide sequences of influenza H9N2 available up to December 25, 2020 from Iran and its neighboring countries (i.e., Pakistan, Afghanistan, Turkmenistan, Armenia, Azerbaijan, Turkey, and Iraq). We also performed a Bayesian Markov chain Monte Carlo method to infer the evolutionary dynamic and the most recent common ancestor for the HA and NA sequences. Results: H9N2 epidemic may have started in Iran and Pakistan much earlier than the other investigated countries in the region, and an ongoing bidirectional dispersion of the virus between the investigated countries was also observed. The mean time of the most recent common ancestor of H9N2 viruses was 1988 for HA, and 1992 for NA. Conclusions: Strains from investigated countries rooted in Pakistan and Iran. Regular surveillance of H9N2 viruses, especially in the live bird markets, enhancing the biosecurity of poultry industry and screening newly arriving immigrants and tourists from neighboring countries at border should be considered to control spread of the virus. Furthermore, surveillance of viral molecular evolution should be initiated for effective prevention of epidemic and pandemic spreads.
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Objective: To determine the temporal patterns of cumulative incidence of brucellosis using autoregressive integrated moving average models. Methods: This cross-sectional study employed yearly and monthly data of 1 117 laboratory-confirmed human brucellosis cases from January 2013 to December 2018 using the Yazd brucellosis national surveillance system. The monthly incidences constructed a timeseries model. The trend of cumulative incidence was perceived by tracing a line plot, which displayed a seasonal trend with periodicity. Thus, the ARIMA models were selected. Thereafter, Akaike information criteria (AIC) and Bayesian information criterion (BIC) values among different models indicated a preferable model from models which were expanded by diverse lags [(3, 0, 3), (2, 0, 3), (3, 0, 2), (4, 0, 3) and (3, 0, 4)]. Then, the achieved ARIMA model was applied to the forecasting cumulative incidence of monthly brucellosis incidences. All analyses were performed using Stata, version 11.2. Results: For the ARIMA (3, 0, 4) model, MAPE value was 56.20% with standard error 0.009-0.016, and white noise diagnostic check (Q=19.79, P=0.975) for the residuals of the selected model showed that the data were completely modelled. The monthly incidences that were fitted by the ARIMA (3, 0, 4) model, with AIC (25.7) and BIC (43.35) with a similar pattern of actual cases from 2013 to 2018 and forecasting incidences from January 2019 to December 2019 were, respectively, 0.50, 0.44, 0.45, 0.49, 0.55, 0.58, 0.56, 0.51, 0.46, 0.44, 0.45 and 0.49 per 100 000 people. Conclusions: In summary, the study showed that the ARIMA (3, 0, 4) model can be applied to forecast human brucellosis patterns in Yazd province, supplementing present surveillance systems, and may be better for health policy-makers and planners.
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Toluene diisocyanate [TDI] is an imperative chemical substance used in the production of polyurethane foams, elastomers, paints and coatings that cause a variety of health problems in workers who are exposed in work places. This study aimed to determine the asthma symptoms and serum specific IgE levels in TDI exposed workers and comparing the results with healthy control group. All the plants that use TDI in the manufacturing of paint and glue in the west of Tehran Province entered to the study and all the workers [550] completed modified initial questionnaire of the NIOSH, the questions were consisted of asthma symptoms. For each symptomatic exposed worker one healthy, sex and age matched control selected. Total IgE and Specific TDI IgE tests were done for each case and control groups. Among 550 TDI exposed workers, 26[4.7%] had asthma symptoms. Nine [34.6%] of symptomatic workers who were exposed to TDI were active cigarette consumer versus 3[11.5%] unexposed workers, P=0.049[CI= 0.953-17.29] OR=4.059. Nine [34.6%] workers had positive family history of atopy versus 1[3.8%] unexposed workers, P=0.0138 [CI= 1.45-305.41] OR=13.24. TDI specific IgE was found in 2 TDI exposed workers and 1 unexposed worker [P=0.5]. Mean of total IgE was 339.05 in exposed workers [P=0.201]. This study provides clinical and paraclinical data of workers exposed to TDI and points to a relation between atopy and smoking habit with asthma symptoms that offer preventing recommendations for TDI exposed workers and their heath administrators
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Leishmania is a significant health problem in many parts of the world. Tumor necrosis factor [TNF] plays an essential role in Leishmania major infections. To study the pro-inflammatory cytokines and antioxidants in four groups of cutaneous leishmaniasis patients. 39 patients were divided into four groups of: 1] active [acute phase of treatment]; 2] non-healing [received treatment for almost two years without recovery]; 3] healing [recovered upon treatment]; and 4] healed [previously received treatment and achieved complete remission] patients. Serum levels of pro-inflammatory cytokines [IL-1B, TNF-alpha, IL-6] and serum antioxidant levels were measured by ELISA and FRAP assays, respectively. While serum antioxidant levels were elevated in the non -healing group, there was no difference among other groups of patients and healthy controls in this regard. Interleukin-1beta showed the highest level in the non-healing group followed by the other groups of patients. The mean serum IL-6 level was highest in the non-healing group, but showed no significant change in the other groups. TNF-alpha and IL-1beta levels were non-significantly elevated in the sera of active and non-healing patients. Pro-inflammatory cytokines IL-1beta, TNF-alpha, IL-6 maybe related to the progression of leishmaniasis. Serum antioxidant levels maybe correlated with patient response to drug treatment.
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Worldwide, numerous people of all ages and ethnicities experience asthma. The achievements of current medical regimens for patients frequently depend on three factors: 1] knowledge of patients regarding this disease, 2] patient's attitude about asthma, including willingness to collaborate with the therapeutic group for disease control, and 3] patient's self-efficacy for controlling asthma. Therefore, this study examined the relationship between knowledge, attitudes, and self-efficacy with socio-economic factors in Iranian asthmatic patients during 2006 - 2008. Participants consisted of 120 adults referred to Milad Hospital, Tehran, Iran during 2006 to 2008 whose physicians diagnosed their asthma. Socio-demographic factors such as sex, age, education level, occupation, marital status, family history of asthma, disease costs, and period of sickness were reviewed. Assessments of knowledge, attitudes and self-efficacy were performed by the Persian version of an international standard questionnaire [KASE-AQ]. Data were analyzed by SPSS version 14. Among respondents, only 9 [7.5%] patients had good knowledge about asthma, 108 [90%] patients had a suitable attitude about their asthma and 103 [85.3%] patients had proper self-efficacy. We found a significant association between self-efficacy and attitude in asthmatic patients [P<0.05]. Although specific knowledge about asthma is low, however, favorable attitudes toward asthma create opportunities to intervene and improve asthma management among patients. However, the use of educational tools depends on patients' educational levels. Therefore, we recommend elevating asthma knowledge