Seroprevalence of Toxoplasma infection in individuals occupationally exposed to livestock and raw meat: A case-control study.

BACKGROUND: The expectancy of Toxoplasma gondii transmitted from livestock and raw meat to humans is a public health problem and is an example of the One Health theory. OBJECTIVES: This survey aimed to determine the seroprevalence and risk factors related to this common infection in individuals occupationally exposed (IOE) to livestock, raw meat and viscera in industrial slaughterhouses and livestock fields in Isfahan province, central Iran. METHODS: This study is a case-control survey carried out on the 401 serum samples of IOE (including slaughterhouse workers, butchers, veterinarians, veterinary technicians, livestock farmers and farm workers) compared to 401 archived samples of the general population (that all matched with cases by region, age and gender). All 802 samples were investigated for anti-T. gondii IgM and anti-T. gondii IgG using enzyme-linked immunosorbent assay. RESULTS: A statistically significant higher anti-T. gondii IgG occurrence (p < 0.001) was observed in IOE compared to the control group (46.1% vs. 31.4%). According to our knowledge, this is the first case-control study on the seroprevalence of anti-T. gondii in IOE to livestock in central Iran. CONCLUSIONS: These findings show a potentially significant association between T. gondii seropositivity and occupational exposure to livestock. Therefore, it is essential to develop guidelines for preventing disease transmission among IOE to livestock, raw meat and viscera in industrial slaughterhouses and livestock fields.

Epidemiology of Bloodstream Infections and Antimicrobial Susceptibility Pattern in ICU and Non-ICU Wards: A Four-Year Retrospective Study in Isfahan, Iran.

Background: Bloodstream infections (BSIs) are one of the causes of morbidity and mortality in hospitalised patients. This study evaluated BSI's incidence, trend, antimicrobial susceptibility patterns and mortality in AL Zahra Hospital in Isfahan, Iran. Materials and Methods: This retrospective study was conducted in AL Zahra Hospital from March 2017 to March 2021. The Iranian nosocomial infection surveillance system was used for data gathering. The data included demographic and hospital data, type of bacteria, and antibiotic susceptibility findings and were analysed in SPSS-18 software. Results: The incidence of BSIs was 1.67% and 0.47%, and the mortality was 30% and 15.2% in the intensive care unit (ICU) and non-ICU wards, respectively. In the ICU, the mortality was correlated with the use of the catheter, type of organism and year of study, but in non-ICU, correlated with age, gender, use of the catheter, ward, year of study and duration between the incidence of BSIs and discharging/death. Staphylococcus epidermidis, Acinetobacter spp. and Klebsiella spp. were the most frequent germs isolated in all wards. Vancomycin (63.6%) and Gentamycin (37.7%) for ICU and Vancomycin (55.6%) and Meropenem (53.3) for other wards were the most sensitive antibiotics. Conclusion: Despite the few rate of BSI in the last four years in AL Zahra Hospital, our data showed that its incidence and mortality in the ICU ward are significantly more than in other hospital wards. We recommend prospective multicentre studies to know the total incidence of BSI, local risk factors and patterns of pathogens causing BSI.

Bacterial Superinfection and Antibiotic Management in Patients with COVID-19 Admitted to Intensive Care Medicine in Central Iran: A Follow-Up Study.

Background: Bacterial superinfections are one of the crucial challenges in patients with coronavirus disease 2019 (COVID-19) that are associated with a high mortality rate. The current study was designed to assess bacterial superinfections and antibiotic management in COVID-19 patients admitted to intensive care unit (ICU). Material and Methods: Seventy-three adult intubated patients with COVID-19 were included in a cross-sectional study. The lung aspirate samples were collected in two stages and assessed for bacterial growth by standard methods. Antimicrobial susceptibility testing was performed using the Kirby-Bauer method as recommended by the Clinical Laboratory Standard Institute guideline (2021 edition). Also, demographic and clinical data were collected. The statistical analysis was done by chisquare test and Student's t-test, and a P value <0.05 was considered significant. Results: Forty men and thirty-three women with a mean age of 64.78 ± 13.90 have included in our study. The mean length of hospitalization and stay in ICU were 18.77 ± 12.94 and 13.51 ± 9.83 days, respectively; 84.9% of cases died. Thirty-three patients had a bacterial superinfection mainly caused by Klebsiella spp and Acinetobacter spp; 21.2% of piperacillin/tazobactam consumers' patients survived that; the differences were significant (p = 0.034). A significant relationship was seen between superinfection and length of hospital stay until intubation (p = 0.033). Conclusion: Bacterial superinfection and mortality rates were relatively high in COVID-19 patients admitted to ICU. According to the results, using beta-lactam/beta-lactamase inhibitors antibiotics in hospitalized patients in ICU can effectively control superinfection.

SARS-CoV-2 Seroprevalence among Health-Care Workers in Isfahan, Iran.

Background: Health-care workers (HCWs) are in the frontline for fighting the coronavirus disease 2019 (COVID-19) pandemic and are at higher risk of acquiring the infection. Therefore, the defining immunity status among HCWs helps mitigate the exposure risk. In this study, we investigated the anti-SARS-CoV-2 immunoglobulin G (IgG) and immunoglobulin M (IgM) and also the associated risk factors in the HCWs working in Isfahan University of Medical Sciences COVID-19 referral hospitals. Materials and Methods: In a cross-sectional study, demographics, COVID-19 symptoms during the past 2 weeks, and health-care details were collected from 200 consenting health workers of COVID-center-hospitals of Isfahan University of Medical Sciences from 23 October to 21 December 2020. The recombinant SARS-CoV2 nucleocapsid protein enzyme-linked immunosorbent assay-based IgM, and IgG antibody tests were evaluated. Data were analyzed using Chi-square and independent-t-student tests, and P < 0.05 was considered significant. Results: One hundred and forty-one women and 59 men with a mean age of 36.4 ± 7.77 years participated in the study. IgG Ab and IgM Ab were positive in 77 (38.5%) and 12 (6%) of samples, respectively, and both antibodies were detected in 9 (4.5%). Higher ages, direct contact with the patients with COVID-19, muscle pain, loss of taste and smell, fever, and cough were the factors associated with antibody seropositivity against SARS-CoV2. Conclusion: This study demonstrated that the prevalence of HCWs with antibodies against SARS-CoV-2 is relatively high in Isfahan University referral hospitals. The development of safety protocols and screening and vaccination strategies in the frontline HCWs must be implemented to reduce the burden of infection.

A Process Evaluation of the Isfahan Antibiotic Awareness Campaign: Developing Engagement on Antimicrobial Resistance.

Background: One of the most prominent global health threats is antibiotic resistance, leading to infection treatment failure. The first Iranian antibiotic awareness week campaign was initiated to improve the prudent use and wise prescription of antibiotics. Materials and Methods: The Isfahan antibiotic awareness campaign was held from November 30 to December 6, 2019, among two targeted populations; the general population and health-care workers by Isfahan University of Medical Sciences. In this campaign held in the main squares, streets, and a city's referral hospital, various educational methods were used to aware and sensitize the general population and medical staff about antibiotics and microbial resistance. These methods include face-to-face training, brochures, advertisement posters and billboards around the city, educational videos, social media messages, retraining for medical doctors and medical specialists, and interviewing in the Islamic Republic of Iran Broadcast. Results: Two hundred and twenty general practitioners, medical specialists, and residents participated in two retraining educational conferences in Al-Zahra Hospital, Isfahan, Iran. The mean score satisfaction of the two conferences was three from four. Nearly 2000 of the general population were under face-to-face educational programs whom after that, 83.6% had the correct answer to the questions around antimicrobial awareness. Conclusions: This campaign was an excellent experience as a pilot study with appealing issues. Further, activities are required to improve engagement with the target population and determine the impact of this campaign on antibiotic consumption and prescription behavior among the public and health-care professionals.

Overuse of Antibiotics: Who is to Blame? A Qualitative Study.

Background: The irrational use of antibiotics seriously threatens global health. Clinicians undoubtedly play an essential role in consuming antibiotics in hospitals and communities, and their attitudes may help the health system's optimal treatment of antibiotics. In this study, we reported clinicians' experiences with antibiotics used in Isfahan, Iran. Methods: In a qualitative study conducted from October 2020 to March 2021, the experiences of 13 clinicians with different clinical specialties were collected through one-to-one interviews. Participants were selected through purposive sampling until data saturation; data collection was conducted through semi-structured interviews. Conventional content analysis was used to analyze the transcribed interviews. The main category was recognized and subcategorized and coded by three researchers. Results: Eight women and five men with a mean work experience of 12.54 ± 10.047 years participated in the study. All of them worried about the overuse of antibiotics and antibiotic resistance. Clinicians believe that the antimicrobial stewardship committee is not active in our country. Laboratory challenges, healthcare providers, the poor performance of the health system, and marketing and business were the main categories of the study. Subcategrories of main categories included inefficiency in the function of laboratories, harmful profit, challenges in medical education, ups and downs of disease treatment, the unacceptable performance of hospitals, failure to upgrade the health system, threats and opportunities, and jobbery. Conclusions: The participants of this study believed that excessive use of antibiotics is a serious challenge in our country. Physicians were concerned about antibiotic resistance and believed that the pattern of antibiotic resistance was not routinely reported. Therefore, in our region, we should make more efforts to collect data in this field and provide this information to physicians. Also, this study confirmed many obstacles to implementing the antimicrobial stewardship program, and the infrastructure needs strengthening. There is also a need for cultural changes and the views of physicians.

Herbal Medicines as Potential Inhibitors of SARS-CoV-2 Infection.

Coronavirus disease 2019 (COVID-19) is the result of infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Understanding molecular pathogenesis is an essential factor for the allocation of effective preventive measures and the development of targeted therapeutics against COVID-19. The genome of SARS-CoV-2 encodes structural and nonstructural proteins, which can be targets for compounds with potential therapeutic ability. On the other hand, the virus life cycle has stages susceptible to targeting by drug compounds. Many natural antiviral compounds have been studied and evaluated at the cellular and molecular levels with antiviral potential. Meanwhile, many studies over the past few months have shown that plant polysaccharides have a good ability to target proteins and stages of the virus life cycle. In this regard, in this review study, the virus specifications and infectious process and structural and functional components of SARSCoV- 2 will be reviewed, and then the latest studies on the effect of plant compounds with more focus on polysaccharides on viral targets and their inhibitory potential on the infectious process of COVID-19 will be discussed.

A Nationwide Study on the Seroprevalence of Measles, Mumps, and Rubella in Iranian Children and Adolescents.

Background: Assessing the prevalence of infections, which are preventable by vaccination, is crucial to monitor the vaccination program efficacy, and it can demonstrate the gaps in population immunity. The current study attempted to assess the specific Immunoglobulin (IgG) antibody against measles, mumps, and rubella (MMR) in Iranian children and adolescents, years after their vaccination. Methods: This cross-sectional study was conducted in Iran. Serum samples of 2100 students, aged 7-18 years, included in a national health survey, were tested for MMR antibodies by ELISA assay. Multistage random cluster sampling was used to select subjects from 30 provinces in Iran. Results: Overall, 1871, 1718, and 1678 serums were tested for measles, mumps, and rubella antibodies, respectively. The prevalence of positive test was 1231 (65.8%) for measles, 1327 (77.2%) for mumps and 1344 (80.1%) for rubella. Conclusion: Despite high vaccination coverage in Iran, IgG antibody against measles, mumps, and rubella was not detected in a considerable proportion of children and adolescents aged 7-18 years. In case of contacts with residents of other countries, where measles or rubella have not yet been eliminated, it may create problems for Iranian children.

Seroprevalence of Bordetella pertussis among a nationally representative sample of Iranian pediatric population: The childhood and adolescence surveillance and prevention of adult noncommunicable disease-V study.

BACKGROUND: Pertussis is a vaccine-preventable respiratory infection and seroepidemiology of the infection could be a marker of the pertussis immunity in a population. In many countries, despite vaccination coverage, high prevalence of pertussis has been observed. The present study aimed to evaluate the immunoglobulin G (IgG) antibody against pertussis and the role of demographic and anthropometric variables on the immunity rate in the Iranian pediatric population to evaluate the impact of existing immunization program in order to envisage future vaccination strategies to prevent infection. METHODS: In a cross-sectional multi-centric study, 1593 samples of the students aged 7-18 years, who had been enrolled in a national survey (Childhood and Adolescence Surveillance and Prevention of Adult Noncommunicable disease-V), were randomly selected and tested for IgG antibody against Bordetella pertussis (BP) by enzyme-linked immunosorbent assay. The age, gender, education, residency, geographical region, and body mass index (BMI) were extracted from the questionnaires of the COSPIAN-Survey. Multiple logistic regression models were used to assess the associations between the variables with the IgG antibody against BP. Data were presented by odds ratio (OR), 95% confidence interval (95% CI) and P values (P): (OR [95% CI]; P). RESULTS: Subjects were consisted of 774 boys and 750 girls, with a mean (standard deviation) age of 12.39 (3.03) years. Overall, BP seroprevalence was 59.8%. There were higher BMI values in seronegative ones versus seropositive (18.62 ± 4.07 vs. 18.15 ± 3.94, P = 0.041, 95% CI = 0.23 [0.02-0.92]). However, the categorized BMI for age was not significantly associated with IgG levels (0.27 [0.25-0.29]; 0.27). BP seroprevalence was not significantly different between geographical regions (0.06 [0.05-0.07]; 0.06), genders (1.17 [0.93-1.47]; 0.18), area of residence (1.07 [0.82-1.4]; 0.61), and educational levels (0.94 [0.75-1.19]; 0.62). CONCLUSION: IgG antibody against pertussis was not detected in nearly 40% of the subjects who had history of vaccination against pertussis. It is recommended to monitor the incidence of pertussis in high-risk populations closely and administer a booster dose of acellular pertussis vaccine in adolescents.

Current status of COVID-19 pandemic; characteristics, diagnosis, prevention, and treatment.

Humans have always been encountered to big infectious diseases outbreak throughout the history. In December 2019, novel coronavirus (COVID-19) was first noticed as an agent causing insidious pneumonia in Wuhan, China. COVID-19 was spread rapidly from Wuhan to the rest of the world. Until late June 2020, it infected more than 10,000,000 people and caused more than 500,000 deaths in almost all of countries in the world, creating a global crisis worse than all previous epidemics and pandemics. In the current review, we gathered and summarized the results of various studies on characteristics, diagnosis, treatment, and prevention of this pandemic crisis.

Molecular evidence and risk factors of Coxiella burnetii among seropositive high-risk individuals in the center of Iran.

This study evaluated the prevalence of C. burnetii DNA in blood samples of the high-risk population in central Iran. In spring 2015, a nested PCR was applied to detect C. burnetii DNA in 173 blood samples from seropositive high-risk individuals in Isfahan County. A checklist was used for extracting data. Univariate tests and multivariable binary logistic regression were performed to analyze the data and P values < 0.05 were considered significant. In total, 9.83% of the samples were positive and an association was found between the prevalence of C. burnetii DNA and the presence of IgG antibodies against phase I and/or II (P = 0.04) in univariate analysis. However, in multivariable logistic regression model, no risk factor was seen. This study revealed that high-risk populations in Isfahan County had been exposed to C. burnetii. This can alert health policymakers to the possibility of a Q fever epidemic in the region.

Detection of Coxiella burnetii and risk factors for infection in ruminants in a central county of Iran.

Q fever is an important zoonosis caused by Coxiella burnetii. This study assessed the prevalence of C. burnetii DNA in blood samples of ruminants and identified the risk factors of infection. In a cross-sectional study, 480 blood samples from 56 herds in Isfahan, Iran were tested for the presence of IS1111 transposon of C. burnetii by nested polymerase chain reaction (PCR). The general information of the herds was collected by a checklist. Univariate tests and a multivariate binary logistic regression model were used and P values less than 0.05 were considered statistically significant. In total, 7.5% of the cattle, 10% of the sheep, and 6.8% of the goats were positive and 25 herds had at least a positive sample. The multivariate logistic regression model showed a lower prevalence rate in herds with fewer than 170 animals (OR: 0.24; 95% CI: 0.11-0.56; P = 0.001). Moreover, ruminants in commercial farms were at lower risk than those in traditional farms (OR: 0.08; 95% CI: 0.01-0.87; P = 0.038). This study confirmed ruminants as important reservoirs of C. burnetii infection in Isfahan County, Iran. Animals in larger herds and traditional farms seem to play a significant role in the transmission of infection. Further studies are recommended on other biological samples such as vaginal mucus or feces.

Seroprevalence of Hepatitis B Infection and Associated Risk Factors among Drug Users in Drop-in Centers of Isfahan, Iran.

BACKGROUND: Scientists perceive drug users (DUs) as a high-risk population for hepatitis B virus (HBV) infection. Effective strategies aiming at the reduction of HBV infection can be depicted when its epidemiological status is clearly defined. The present study provides new insight into associated risk factors of HBV infection and its seroepidemiological status among DUs attending drop-in centers (DICs). METHODS: This was a cross-sectional study, which was implemented in 7 DICs of Isfahan province. The sample size included 539 participants. Demographic data and risk factors for HBV infection were obtained by a trained social worker using a self-made structured questionnaire. Venous blood sample was obtained and tested for hepatitis B surface antigen (HBsAg), hepatitis B surface antibody, and total hepatitis B core antibody (HBcAb) using enzyme-linked immunosorbent assay. RESULTS: Mean age of the participants was 31.76 ± 8.4 years. They were generally male, Iranian, urban, with an education level of high school or less. The prevalence of HBV infection (HBsAg and/or HBcAb) was 18% (88.490). Regression analysis showed that age, bloodletting, and drug injection, being the sexual partner of injecting DU (IDU), as well as frequency and duration of imprisonment positively correlated with HBV infection. CONCLUSIONS: Drug injection bloodletting, and being the sexual partner of IDU, as well as frequency and duration of imprisonment could be considered as contributing factors in HBV infection.

Epidemiology of Q fever in Iran: A systematic review and meta-analysis for estimating serological and molecular prevalence.

BACKGROUND: Q fever is endemic in Iran, thus, we conducted a systematic review and meta-analysis on epidemiology of Coxiella burnetii among humans and animals in Iran. MATERIALS AND METHODS: A systematic search was performed to identify all articles reporting C. burnetii prevalence in Iranian humans or animals, published from January 2000 to January 2015. Data from articles were extracted, and a pooled estimate of prevalence with corresponding 95% confidence interval (CI) was calculated using random effect method. RESULTS: In this review, 27 papers were identified. The pooled seroprevalence of Q fever in animals was 27% (CI 95%: 23%-32%). The prevalence was 33% (CI 95%: 22%-45%) in goats, 27% (CI 95%: 21%-32%) in sheep, and 17% (CI 95%: 5%-28%) in cattle. The bacterial DNA was detected in 5% (95% CI: 3%-9%) of milk samples, and it was higher in cattle (10%; 95% CI: 6%-16%) than sheep (2%; 95% CI: 0-7%) and goats (4%; 95% CI: 0-12%). CONCLUSION: C. burnetii DNA or its antibody has been frequently detected among ruminants. Since these animals can transmit the infection to humans, Q fever could be a potential health problem in Iran.

Seroprevalence and risk factors of Coxiella burnetii infection among high-risk population in center of Iran, a neglected health problem.

In order to evaluate the prevalence of antibodies against phase I and II antigens of Coxiella Burnetii and to identify related risk factors among high-risk groups in the center of Iran, a serological survey was performed in Isfahan County. In a cross-sectional study, 401 sera were collected from slaughterhouse workers, butchers, farmers and veterinarians in spring 2015. Samples were tested for specific immunoglobulin G (IgG) antibodies against phase I and II of C. burnetii by indirect immunofluorescence assay. A checklist was fulfilled to document demographic information. Univariate analysis and multivariable binary logistic regression model were used to analyze data. IgG antibodies against phases I and II of C. burnetii were detected in 19% and 36.9% of participants, respectively. The overall seropositivity (IgG against phase I and/or II) was 43.1%. The present study shows a high seroprevalence of C. burnetii infection among high-risk population in center of Iran. It is suggested to carry out occupational health monitoring programs for individuals who may be exposed to C. burnetii.

Detection and risk factors of Coxiella burnetii infection in dairy cattle based on bulk tank milk samples in center of Iran.

Infection with Coxiella burnetii has a worldwide distribution in ruminants and is associated with abortions and reproductive problems in this group of animals. This study aimed to determine the prevalence of C. burnetii DNA in bulk tank milk (BTM) of dairy cattle herds and to identify the risk factors of infection. This cross-sectional study was conducted in spring 2015. A total of 163 BTM samples from 74 commercial and 89 traditional dairy cattle herds in Isfahan, Iran was tested for the IS1111 transposon of C. burnetii by real-time polymerase chain reaction (PCR). A checklist containing general information of the herds was filled for each farm. Data were analyzed using univariate tests (chi square and t-tests) and multivariable binary logistic regression analysis. Bacterial DNA was detected in 8.6% of the samples (95% CI: 4.2- 12.9). In univariate analysis, the prevalence rate was higher in traditional herds than in commercial herds (n=12; 13.5% vs. n=2; 2.7%; P=0.01). The prevalence rate was inversely associated with the size and infection control score of the herd. In multivariable binary logistic regression, however, only herd size was found to be related with the infection rate, i.e. herds with ≥80 cattle were less likely to be infected (OR: 0.07; 95% CI: 0.01- 0.77; P=0.03). The only identified risk factor for this infection was the herd size. In fact, smaller herds (size <80) were more likely to be infected.

Mustard gas exposure in Iran-Iraq war - A scientometric study.

BACKGROUND: The Iranian victims of sulfur mustard attack are now more than 20 years post-exposure and form a valuable cohort for studying the chronic effects of an exposure to sulfur mustard. Articles on sulfur mustard exposure in Iran-Iraq war were reviewed using three known international databases such as Scopus, Medline, and ISI. The objectives of the study were measurement of the author-wise distribution, year-wise distribution, subject area wise, and assessment of highly cited articles. MATERIALS AND METHODS: We searched three known international databases, Scopus, Medline, and the international statistical institute (ISI), for articles related to mustard gas exposure in Iran-Iraq war, published between 1988 and 2012. The results were analyzed using scientometric methods. RESULTS: During the 24 years under examination, about 90 papers were published in the field of mustard gas in Iran-Iraq war. Original article was the most used document type forming 51.4% of all the publications. The number of articles devoted to mustard gas and Iran-Iraq war research increased more than 10-fold, from 1 in 1988 to 11 in 2011. Most of the published articles (45.7%) included clinical and paraclinical investigations of sulfur mustard in Iranian victims. The most highly productive author was Ghanei who occupied the first rank in the number of publications with 20 papers. The affiliation of most of the researchers was Baqiyatallah Medical Sciences University (research center of chemical injuries and dermatology department) in Iran. CONCLUSION: This article has highlighted the quantitative share of Iran in articles on sulfur mustard and lays the groundwork for further research on various aspects of related problems.

Surveillance of acute respiratory infections among outpatients: A pilot study in Isfahan city.

BACKGROUND: Considering that there was not any regional survey in Isfahan, Iran regarding the epidemiology of acute respiratory tract infections (ARTI) in different age groups of general population, the aim of this study was to determine the epidemiologic feature of ARTIs in Isfahan using multiplex polymerase chain reaction (PCR) method. MATERIALS AND METHODS: In this cross-sectional study, patients aged <80 years with symptoms of ARTI were studied, during 2009-2010 Nasopharyngeal and dry throat swab specimens were collected and pathogens of ARTI was determined using multiplex real-time PCR. RESULTS: In this study, 455 cases with ARTI were studied. Mean age of studied population was 29.9 ± 18.5 (range: 0.2-80). Symptoms such as sore throat (86.3%), coryza (68.0%) and dry cough (54.3%) were the most common symptoms in all studied groups, whereas fever was the most clinical presentation of younger patients (<15 years old) and headache and skeletal pain were the most common symptoms of older patients (>15 years old). Rhinovirus was the most common cause of ARTI in patients aged <5 years and those aged >50 years. Influenza virus B was the most common cause of ARTI in patients aged 5-50 years. CONCLUSION: Our study provides baseline information on the epidemiologic and clinical feature of outpatients with ARTIs in Isfahan city. Though our findings in this pilot study could be helpful in diagnosis, treatment, and prevention of ARTI, planning preventive interventional.

The prevalence of isolated hepatitis B core antibody and its related risk factors among male injected drug users in Isfahan prisons.

BACKGROUND: The prevalence of isolated hepatitis B core antibody (anti-HBc) varies between 1% and 30% in different populations. Isolated anti-HBc-positive patients who suffer from occult hepatitis B virus (HBV) infection have the potential to transmit HBV infection. So isolated anti-HBc screening is a valuable tool to prevent HBV transmission. Considering the importance of isolated anti-HBc screening and high prevalence of HBV among injected drug users (IDU) prisoners, we designed this study to evaluate the isolated anti-HBc positivity among inmates with the history of IDU in our area. MATERIALS AND METHODS: We did this cross-sectional study from September 2009 to March 2010 among volunteer male IDU prisoners in Isfahan. Blood samples were taken from all of subjects and tested for HBV markers. Then a questionnaire containing socio-demographic, drug histories and high risk behaviors information was completed for all participants. Data analysis was done utilizing univariate analysis and multiple logistic regressions. A P < 0.05 was considered significant. RESULTS: Totally 970 male IDU prisoners (mean age 32.6 ± 8.1) were included in our study. The prevalence of isolated HBc Ab was 4.5%. Isolated anti-HBc significantly was related to tooth filling (OR: 2.62, CI: 1.20-7.14) and imprisonment (OR: 3.95, CI: 1.39-11.18). We couldn't find any relationship between isolated anti-HBc positivity and addiction duration, incarceration frequency, recent incarceration duration or number of injection per month. CONCLUSION: For screening high risk groups in parallel with hepatitis B surface antigen (HBsAg), hepatitis B surface antibody (HBsAb) and other viral markers, maybe it is better to check HBcAb too, because isolated HBcAb-positive patients may have occult hepatitis B infection which could transfer the infection to others.