Vol 50 No 7 (2021)

Published: 2021-07-01

Editorial

Review Article(s)

  • XML | PDF | downloads: 147 | views: 174 | pages: 1303-1310

    Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was transported from China to Iran via passengers. The virus is transmitted through droplets from coughing, sneezing, talking and contact with infected surfaces. Due to high transmissibility in places such as clinics, medical offices, buses and offices where there are large crowds, it spread rapidly in Iran and caused the mortality of a significant number of people, especially the elderly with underlying disease. Preventing travel and gatherings, as well as applying house quarantine in Apr 2020, reduced COVID-19 somewhat but then due to lack of attention to social distancing, reducing the use of masks by the people and inappropriate decisions by the national committee on combating coronavirus (NCCC), including reducing the working hours of public offices and shops, reducing the staff of government offices, monopoly on the distribution of essential materials and supplies, the presence of overcrowding in clinics of medical centers, hospitals, and private clinics caused the decline of the disease in the country to decrease. Measures can be taken to prevent the spread of the virus as much as possible, including: rapid detection of infected people, their isolation, contact tracing, quarantine of people over 65 and under 15, protection of the elderly, prevention of gatherings, forcing the use of protective equipment in possible gatherings, and electronicizing public services.

  • XML | PDF | downloads: 127 | views: 138 | pages: 1311-1323

    Background: The prevalence and risk factors of urinary tract infection (UTI) in neonates with unexplained hyperbilirubinemia are not studied thoroughly. Since the prevalence of UTI is highly variable in different areas and countries, this study aimed to review the existing data of Iranian neonates with UTI presented with unexplained hyperbilirubinemia.

    Methods: This study is a meta-analysis of Iranian newborns with unexplained hyperbilirubinemia. We identified all studies indexed in international (Web of Science, PubMed, Scopus, Google Scholar) and national (Science Information Database, Magiran) databases from 2000-2018. Search terms included: Urinary Tract Infections OR UTI AND urine OR culture OR microbio, jaundice OR icter OR hyperbili, AND Iran.

    Results: Overall, 4210 neonates from 17 studies were included. The pooled prevalence of UTI in neonates with unexplained hyperbilirubinemia was 6.81% (95% CI: 4.86-8.77). Considering the subgroups analyses; the prevalence of UTI was higher in the prolonged vs. not-prolonged state (8.34% vs. 4.00%), low birth weight vs. normal birth weight (7.81% vs. 4.51%), and exclusive vs. non-exclusive breastfeeding (8.84% vs. 4.72%). Male gender and low birth weight increased the risk of UTI about two times compared to the female gender and normal birth weight, respectively. The results of the analyses in neonates with unconjugated hyperbilirubinemia also showed the above-mentioned subgroup differences.

Original Article(s)

  • XML | PDF | downloads: 143 | views: 141 | pages: 1324-1333

    Background: This study investigated the impact of socio-economic factors on the spread and outbreak of COVID-19 based on Chinese data.

    Methods: Cumulative confirmed cases were collected and divided into the First-stage cases cluster dominated by imported cases, and the Second-stage cases cluster dominated by secondary cases, according to the time of emergency state and Wuhan city lockdown. The linear regression was used for data analysis.

    Results: A total of 12,877 cases in 30 provinces were analyzed in the study. The First-stage cases cluster included 675 cases and Second-stage cases cluster included 12,202 cases. The socio-economic factors were significantly associated with the cases (P<0.05). The GDP and proportion of population moving out of Wuhan were associate with the First-stage dominated by imported cases (b>0, P<0.05). The First-stage cases cluster, proportion of population moving out of Wuhan and urban population were associate with the Second-stage dominated by secondary cases (b>0, P<0.05).

    Conclusion: Socio-economic factors had impacts on the spread and outbreak of COVID-19. The combination of different socio-economic indicators at different stages of the epidemic may help control the epidemic.

  • XML | PDF | downloads: 137 | views: 159 | pages: 1334-1342

    Background: We aimed to conduct a mindfulness yoga program to treat the psychological problems of middle-aged men by examining the effects of a mindfulness yoga program on depression, self-esteem, and quality of life in this population.

    Methods: The participants included 50 middle-aged men (aged 40–60 yr) living in Seongnam-si, Korea. Twenty-five men were randomly assigned to the experimental group and 25 were assigned to the control group. The mindfulness yoga program was conducted twice a week for 12 weeks, and each session lasted approximately 75 min. Before the first session, a pre-test was conducted, after which the program began. Questionnaires were completed after the 4th, 8th, and 12th weeks of the program, and the control group underwent psychological tests at the same time points. A two-way (2 × 4) repeated measures analysis of variance was conducted, and when the interaction effect was significant, a post-hoc test (Bonferroni) was performed.

    Results: In the intervention group, depression severity significantly decreased (P<0.001) and self-esteem significantly increased (P<0.01). Furthermore, the intervention group also showed a significant increase in psychological (P<0.001), social (P<0.001), and overall quality of life (P<0.001) among the sub-dimensions of quality of life.

    Conclusion: Middle-aged men should be made aware of the usefulness of mindfulness yoga and encouraged to participate in such programs. Mindfulness yoga may be considered as an alternative treatment strategy that promotes the natural healing and management of psychological issues faced by middle-aged men.

  • XML | PDF | downloads: 75 | views: 119 | pages: 1343-1351

    Background: Palliative care is an essential part of medical practice, however, it has developed slowly in China. We aimed to analyze the current situations of the cognition on palliative care among the nurses in Shandong Province, China.

    Methods: This was a cross sectional study. Investigation of 1050 nurses came from 5 third-class hospitals and 5 second-class hospitals in Shandong Province, China from Jul to Oct in 2018. The questionnaire included 4 parts: general information of the subject, the questionnaire of palliative nursing knowledge, attitude, and the behavior. Data were collected by the APP. Overall, after eliminating the invalid questionnaires, 1026 questionnaires were included in the final analyses. The software Stata 14.2 was used for all statistical analyses.

    Results: The score of knowledge and attitude was low, the practice was higher. Multivariate analysis results: the significant independent variables of univariate analysis were included in the multivariate non-conditional logistic regression model for analysis. Some departments had statistical significance in knowledge multivariate Logistic regression analysis. The multivariate logistic regression analysis of practice was significant for physical health and religious beliefs. The statistical variables of the total score of cognition were gender, age of care, health status and religious beliefs.

    Conclusion: Nursing knowledge is lacking and attitude remains to be improved as soon as possible. It is vital to improve the cognition of palliative care of nurses in Shandong general hospitals by developing relevant rules and regulations, strengthening the supervision of relevant ant departments, and enhancing training for nurses.

  • XML | PDF | downloads: 74 | views: 123 | pages: 1352-1360

    Background: We aimed to compare demographic, health-related characteristics, and quality of life between adults with cardiovascular or metabolic diseases and the general population.

    Methods: Data from 25,712 adults assessed on the Korea National Health and Nutrition Examination Survey V & VI (2010–2013) were analyzed for differences in health-related quality of life.

    Results: The corrected EuroQol-5 Dimension score mean among participants with cardiovascular or metabolic diseases was significantly lower than for the general population across all five dimensions (P<0.001). Individuals with cardiovascular disease had lower quality of life than those with metabolic diseases.

    Conclusion: Adults with cardiovascular or metabolic diseases reported lower health-related quality of life in all domains when compared to adults in the general population. Therefore, interventions and management to improve quality of life among patients with cardiovascular or metabolic diseases are necessary.

     

     

     

     

     

  • XML | PDF | downloads: 80 | views: 119 | pages: 1361-1371

    Background: There is a lack of specific study of the suboptimal health status (SHS) in software programmers. The aims of the present study were to investigate the prevalence of SHS and analyze the influencing factors among Chinese software programmers.

    Methods: A cross-sectional survey using a programmer SHS scale was conducted to evaluate the prevalence of SHS, as well chi-square test and multi-factor logistic regression were applied to analyze the relationship between suboptimal health and personal basic information, living and work habits in software programmers.

    Results: The prevalence of SHS was 18.67% in software programmers. Single factor analysis found that there were differences in suboptimal health prevalence among different work cities (P = 0.031), hours of sleep per day (P = 0.046), overtime days per month (P = 0.010) and exercise frequency per week (P = 0.015). The factors for suboptimal health such as hours of sleep per day (OR = 0.307, 95% CI = 0.096~0.984) and exercise frequency per week (OR = 0.190, 95% CI = 0.054~0.671) significantly affected subjects of SHS via multi-factor logistic regression analysis, indicating that adequate sleep and exercise decreased the chance of SHS up to 30.70% and 19.00%, respectively.

    Conclusion: Suboptimal health had become a serious public health challenge in Chinese software programmers. Whilst, the health status of the programmers could be effectively elevated by improving lifestyles.

  • XML | PDF | downloads: 56 | views: 119 | pages: 1372-1380

    Background: Multiple Imputation (MI) is known as an effective method for handling missing data in public health research. However, it is not clear that the method will be effective when the data contain a high percentage of missing observations on a variable.

    Methods: Using data from “Predictive Study of Coronary Heart Disease” study, this study examined the effectiveness of multiple imputation in data with 20% missing to 80% missing observations using absolute bias (|bias|) and Root Mean Square Error (RMSE) of MI measured under Missing Completely at Random (MCAR), Missing at Random (MAR), and Not Missing at Random (NMAR) assumptions.

    Results: The |bias| and RMSE of MI was much smaller than of the results of CCA under all missing mechanisms, especially with a high percentage of missing. In addition, the |bias| and RMSE of MI were consistent regardless of increasing imputation numbers from M=10 to M=50. Moreover, when comparing imputation mechanisms, MCMC method had universally smaller |bias| and RMSE than those of Regression method and Predictive Mean Matching method under all missing mechanisms.

    Conclusion: As missing percentages become higher, using MI is recommended, because MI produced less biased estimates under all missing mechanisms. However, when large proportions of data are missing, other things need to be considered such as the number of imputations, imputation mechanisms, and missing data mechanisms for proper imputation.

  • XML | PDF | downloads: 49 | views: 87 | pages: 1381-1388

    Background: To analyze whether the area differences of RTIs (road traffic injuries, RTIs) caused by unequal development in China, provide suggestions for the prevention of the RTIs.

    Methods: The data of RTIs in China was collected from the authoritative official website and yearbook of China.

    Results: Total RTIs in the East was the highest (RTIs frequency: 591789; injured people: 600611; death toll: 168885; economic loss: 27.22 billion RMB), followed by the Center (RTIs frequency: 321807; injured people: 352769; death toll: 91966; economic loss: 23.90 billion RMB) and the lowest in the West (RTIs frequency: 289482; injured people: 332517; death toll: 101095; economic loss: 16.35 billion RMB). The multivariate linear correlation and regression showed that the characteristic of RTIs was highly related with GDP (r=0.99, P < 0.001).

    Conclusion: The economically developed areas had a large amount of traffic damages. The government should focus on preventing high RTIs in the East and high death tolls in the West.

  • XML | PDF | downloads: 71 | views: 129 | pages: 1389-1397

    Background: This study was planned to investigate the cause, method, age group and gender of suicides between 2009 and 2017 in Turkey.

    Methods: Data on suicide deaths between the years 2009-2017 were obtained from the death data of the Turkish Statistical Institute.

    Results: Suicide data were evaluated according to age group, gender, reason and method. The most common suicide methods among people living in Turkey were hanging oneself, using a firearm and throwing oneself from a high place whereas common causes and unknown causes were found to be illness and economic problems. Gender showed statistical significance in the cause of suicide in all suicide methods (illness, economic problems, job failure). According to age groups the reasons were  family disharmony, emotional relationship and not being able to marry the desired person, Education failure were found to be statistically significant. Less used methods to commit suicide in Turkey were determined as using firearms, using natural gas or LPG, throwing from a train or motor vehicle.

    Conclusion: It is a very sad situation for an individual to end his/her life conspiratorially. Appropriately collected suicide information can guide the design of suicide prevention strategies. Because previous suicide attempts seem to be an important risk factor for future attempts and death by suicide.

  • XML | PDF | downloads: 55 | views: 127 | pages: 1398-1404

    Background: To explore the effects of predictive nursing intervention among patients with acute stroke.

    Methods: One hundred and sixty participants were included. They were hospitalized in the Department of Neurology of a third-level first-class hospital in Changsha, Hunan Province, from January to August 2019. They were categorized into control group and intervention group by random number table, with 80 patients in each group. General nursing for patients in Neurology Department was offered to the control group. On the basis of general nursing, predictive nursing intervention was offered to the intervention group. The effectiveness of predictive nursing intervention were evaluated by disparity in neurologic function, movement function, daily life ability and sleep quality before intervention and 2 weeks after intervention. The neurologic function, movement function, daily life ability and sleep quality were evaluated by National Institute of Health acute stroke scale (NIHSS), Fugl-Meyer scale, Barthel indicator, and Pittsburgh sleep quality indicator (PSQI), respectively.

    Results: There was no significant difference in gender, age, complications and treatment methods between two groups. There was no significant difference in the scores of NIHSS, Fugl-Meyer scale, Barthel indicator, and PSQI before intervention. The scores of NIHSS and PSQI were significantly lower in the intervention group than those in the control group, and the scores of Fugl-Meyer scale and Barthel indicator were significantly higher in the intervention group than those in the control group (P <0.05).

    Conclusion: Predictive nursing intervention could help improve not only neurologic function, movement function, and daily life ability, but also sleep quality among patients with acute stroke.

  • XML | PDF | downloads: 38 | views: 89 | pages: 1405-1415

    Background: We aimed to compare the prediction efficiency of back propagation (BP) network and grey model (GM) (1.1) for mumps infectious diseases and compare the application effect of the two models.

    Methods: By calculating the average incidence rate of mumps in January 2014 -2016, we conducted the modeling of the BP time series, GM (1,1) grey model and the combination models of them, and predicted the incidence rate in June 2016 in comparison with the actual one. We compared the quarterly incidence rate to test the two prediction models, and compared the advantages and disadvantages of these models.

    Results: R value of BP model was 68.45%, for GM (1,1) was 58.49%, and for combined forecasting model was 86.95%. We used the principal component analysis clustering method to control the samples, and found that the samples were close to the population mean. We found that the GM (1.1) model was more suitable for the prediction of mumps infection mode. We carried out dimension reduction analysis on the model data, and the accuracy of the data after dimension reduction is within the range of Da. For the discrete degree of the data in the combined model, matlab pipeline was used to verify the reliability of the data and results. By calculation after manifold optimization small error probability was P=0.875 and semi mean relative error 2.43%.

    Conclusion: BP, GM (1,1) is a better method for modeling the epidemic trend of mumps in China, but the efficiency of prediction is not as high as the combination of them.

  • XML | PDF | downloads: 44 | views: 82 | pages: 1416-1420

    Background: We aimed to explore the influencing factors of clinical adverse blood transfusion reactions, to provide theoretical basis and support for clinical safe blood transfusion, and to minimize the occurrence of adverse blood transfusion reactions.

    Methods: The method was to retrospectively analyze the report of adverse blood transfusion reports from 6 hospitals in Linyi area, Shandong, China to the blood station in Linyi City center from 2013 to 2020. We aimed to classify factors, analyze the occurrence of adverse transfusion reactions, and discuss the correlation between the occurrence of adverse transfusion reactions and the above factors.

    Results: Overall, 248 patients (77.98%) had a history of blood transfusion. The difference between this group and the group with no history was statistically significant (P<0.05). The incidence of adverse transfusion reactions in middle-aged and elderly patients was relatively high, especially for those over 50 yr old, with an adverse reaction of 135, for example, the proportion reached 42.45%. In addition, a retrospective analysis found that the occurrence of adverse transfusion reactions was mostly concentrated from Mar to Sep, a total of 228 cases, accounting for 71.69% of all adverse reactions, which was the highest incidence of adverse transfusion reactions.

    Conclusion: The main adverse reactions of transfusion were allergic reactions, followed by non-hemolytic febrile reactions, mainly caused by transfusion of suspended red blood cells.

  • XML | PDF | downloads: 49 | views: 77 | pages: 1421-1427

    Background: We aimed to provide data regarding COVID-19 infection and mortality rates within different specialties of physicians and general medical practitioners in a longitudinal nationwide study and to compare the results with general population.

    Methods: Data on COVID-19 infection and mortality of medical physicians in Iran was actively gathered through the Iranian Medical Council (IRIMC). Population COVID-19 cumulative incidence and mortality data were extracted from WHO situation analysis reports and data on Iranian population were obtained from the Statistical Center of Iran.

    Results: As of Jul 27th 2020, COVID-19 infection and mortality rates were 0.680% and 0.0396% among 131223 physicians. The highest cumulative infection rates as of 27th July 2020, were observed in specialists of infectious diseases (3.14%) followed by neurology (2.18%), and internal medicine (2.13%). The highest cumulative mortality rates as of Nov 3rd 2020 were observed in specialties of forensic medicine (0.314%), anesthesiology (0.277%), urology (0.237%), and infectious diseases (0.20%). Male physicians comprised 95% of cumulative mortality as of Nov 3rd. The physicians’ COVID-19 mortality in July and November were 49% and 23% higher than the general population respectively.

    Conclusion: Infection and mortality rates in Iranian physicians were higher than the general population, however the magnitude of difference was narrowing in longitudinal investigation. Provision of personnel protective equipment should be prioritized to specialists of infectious diseases, forensic medicine, anesthesiology, internal and emergency medicine, and urology.

  • XML | PDF | downloads: 90 | views: 167 | pages: 1428-1435

    Background: Paying attention to the issue of mental health in the workplace, especially with current pandemic conditions of COVID-19 is of significant importance. Therefore, this study aimed to determine the factors affecting occupational burnout among health care center staff during the pandemic of coronavirus infection.

    Methods: The present study was a case-control study carried out in the first half of the year 2020 on medical staff working in hospitals in Tehran. The sample size was 324 individuals, including 175 employees working in general (non-COVID) wards and 149 people working in COVID-19 wards. Demographic characteristics questionnaire and two standard questionnaires of Maslach Burnout Inventory and Parker and DeCotiis Job Stress Scale were distributed.

    Results: Total score of job stress and its two dimensions (time and pressure) had a significant relationship with different levels of occupational burnout. Logistic regression analyses showed significant relations between job stress with emotional exhaustion (95% CI, 1.11-1.19, OR=1.15) and depersonalization. Participants in both wards experienced statistically significant increasing trends given the different components of occupational burnout concurrently by increasing their total stress score.

    Conclusion: Hospital staff’s levels of stress and occupational burnout regardless of where they worked (COVID-19 wards or general wards) were not significantly different and existed among the members of both groups. On the other hand, job stress and its dimensions (time pressure and anxiety) had a significant relationship with the main dimensions of occupational burnout.

  • XML | PDF | downloads: 58 | views: 74 | pages: 1436-1444

    Background: Chemokines are proinflammatory cytokines that play key roles in development of cardiovascular diseases (CVD). Chemokine-induced recruitment of peripheral leucocytes to tissues is a crucial step in the CVD progression. CC chemokines ligand 5, 2 (CCL5 and CCL2), have been characterized as emerging inflammatory biomarkers of atherosclerotic CVD. The aim of this study was to find out whether genetic polymorphisms of CCL5 -403 G>A (rs2107538) and CCL2 –927 G>C, (rs3760396) were associated with the risk of CVD.

    Methods: In this case-control study, 500 Iranian individuals including 250 CVD patients and 250 healthy subjects as the control group participated in 2017. Genotyping of CCL5 -403 G>A and CCL2 –927 G>C polymorphisms were executed using Tetra-ARMS PCR method.

    Results: At genotypic level both CCL5 -403 G>A and CCL2 –927 G>C polymorphisms were not associated with the risk of CVD (P>0.05), even after adjustment by age, sex, race, and history of hypertension, DM and smoking. However, the CCL2 –927 C allele was associated with an increased risk of CVD (OR=1.42, P=0.050) with a higher prevalence in CVD patient than in controls (17% vs. 12%). Moreover, the haplotype analysis revealed that CCL5/CCL2 haplotype (G/C) was a risk factor for CVD (OR=2.13, P=0.001), and that carriers of this haplotype were at 2.13-fold higher risk of CVD than subjects with G/G haplotype.

    Conclusion: CCL2 –927 C variant and CCL5/CCL2 haplotype (G/C) were associated with susceptibility to CVD, and were risk factors for CVD in our population but more studies with large sample size are recommended.

  • XML | PDF | downloads: 49 | views: 71 | pages: 1445-1453

    Background: Although major dietary patterns and sleep quality independently affect psychiatric disorders, their interactive association on depression is not clear. This study assesses the independent association of dietary patterns and sleep quality on depression, and also investigates their interactive associations on depression among overweight and obese women in Iran

    Methods: Cross-sectional study was conducted among 304 participants, age 18 and above in 2018 at Tehran Iran. Usual dietary intake was collected with 174-FFQ. Participants’ biochemical parameters and depression were measured using standard protocol. Major dietary patterns were extracted by factor analysis and grouped into Fruits&Vegetable group (healthy dietary pattern), High Fat diary&Red Meat group (unhealthy dietary pattern) and Crackers&High Energy Drinks group (western dietary patterns).

    Results: After adjusting for confounders poor sleep was associated with moderate and high depression; AOR (95%CI): 0.41(0.19-0.90) and 0.29(0.13-0.60) respectively. However, healthy dietary patterns (tertiles 2nd and 3rd) interact with sleep for depression; AOR (95%CI): 4.168(1.166-14.992) and 2.966(1.068-8.234) respectively. Unhealthy dietary pattern tertiles 2nd and 3rd interact with sleep for depression; AOR (95%CI): 2.925(1.055-8.113) and 4.216(1.182-15.042) respectively and Western dietary pattern tertile 3rd interacts with sleep for depression; AOR (95%CI): 4.264(1.494-12.169).

    Conclusion: Sleep deprivation could be associated with depression. However, sleep quality could interacts with dietary patterns to be associate with depression among overweight and obese people.

  • XML | PDF | downloads: 50 | views: 94 | pages: 1454-1462

    Background: Bordetella pertussis, a highly contagious respiratory. Notably, the resurgence of pertussis has recently been associated with the lacking production of vaccine virulence factors. This study aimed to screen pertactin (Prn) and filamentous hemagglutinin (Fha) production in Iran with 50 years' whole cell vaccine (WCV) immunization program.

    Methods: Overall, 130 B. pertussis isolates collected from Pertussis Reference Laboratory of Iran during 2005-2018. Real-time PCR was performed by targeting IS481, ptxP, IS1001 and IS1002 for species confirmation of B. pertussis. Western-blot was used to evaluate the expression of virulence factors (pertactin and filamentous hemagglutinin).

    Results: All tested B. pertussis isolates expressed Prn and all except two isolates expressed Fha. We have sequenced genomes of these strains and identified differences compared with genome reference B. pertussis Tohama I.

    Conclusion: Many countries reporting Prn and Fha-deficiency due to acellular vaccine (ACV) pressure. Our results demonstrate in a country with WCV history, Fha-deficient isolates may rise independently. However, Prn-deficient isolates are more under the ACV pressure in B. pertussis isolates. Continues surveillance will provide a better understanding of the effect of WCV on the evolution of the pathogen deficiency.

  • XML | PDF | downloads: 56 | views: 99 | pages: 1463-1473

    Background: This study was conducted with a long-term vision (2014-2025) targeted workforce requirement projection by occupational groups in Iran’s health sector.

    Methods: The “modified & combined model” used including Hall Model and Australian health workforce estimation model. It was a need-based approach with three components of estimation; requirements, supply with current growth and net required workforce. Requirement estimated by three assumptions: active workforce calculation; the growth of health service delivery resources and facilities; and daily individual working hours, created eight different scenarios. Economic feasibility of each scenario determined. To forecast the supply, used accurate numbers of the existing pool of practicing workforce in addition to inflows, minus losses from the profession. To calculate total recruits required, base year stock deducted from projected requirement and by adding Net flow, recruits required calculated.

    Results: The health sector will need 781,887 workforces to realize service's needs. Workforce supply with the existing trend in the target year was 799,347. Therefore, workforce balance would be 17,460 surpluses. Moreover, to estimate required workforce and substitution number for the exited ones during the study periods till the target year, 547,136 individuals should be recruited mostly nurses and physicians.

    Conclusion: Limiting the workforce required to economic feasibility challenge workforce accessibility in the future as it is sensed in present tense as well. Therefore, in addition augmenting GDP and health funds, it is necessary alternative policies such as increasing share of health sector from GDP, prioritization of workforce needs or moving towards other proper policies.

  • XML | PDF | downloads: 42 | views: 77 | pages: 1474-1482

    Background: Bacterial spores are among the most efficient vaccine delivery vehicles. Because of their safety and efficacy, Bacillus subtilis spores are increasingly used in this regard. The negatively charged surfaces of the spores allow antigens to be adsorbed onto these structures. In this study, a candidate vaccine against Salmonella enterica serovar Typhi was adsorbed onto B. subtilis spores and the immunogenicity of the formulation was investigated in BALB/c mice.

    Methods: This work was performed during 2018-2019 in Islamic Azad University of Lahijan. FliC protein was recombinantly expressed in E. coli BL21 (DE3) cells and purified by affinity chromatography. On the other hand, B. subtilis strain PY79 (ATCC1609) was cultured in DSM medium and after the sporulation, FliC protein was adsorbed onto the spores in three different pH values (4, 7 and 10) and the adsorption was verified using dot-blot assay. FliC-adsorbed spores were then administered to BALB/c mice through the subcutaneous route. Mice immunization was evaluated by serum IgG assessment and challenge study.

    Results: FliC protein was successfully expressed and purified. Sporulation was controlled by phase-contrast microscopy. Serum IgG assay showed significant stimulation of the mice's humoral immune system. Immunized mice were able to resist bacterial infection.

    Conclusion: The results showed the efficiency of spores as natural adjuvants for the stimulation of mice immune system. The formulation can be exploited for the delivery of recombinant vaccines against bacterial pathogens.

Letter to the Editor