Background: The extent of infection by coronavirus disease 2019 has not been well known. In this study we aimed to determine seropositivity of COVID-19 virus infection in population of a highly affected area in north of Iran. Methods:In a population-based cluster random sampling design through phone call invitation, a total of 196 household including 551 subjects agreed to participate in this study. Each participant were taken 50ml blood sample at health care center. Rapid test kits were used to detect antibody against COVID-19. Crude, population-weight adjusted and test performance adjusted prevalence of antibody seropositivity to SARS-CoV-2 were reported. Results:The prevalence of antibody seropositivity was 22% (95%CI: 19-26%). The population weight adjusted estimate was 21% (95%CI: 14-29%) and test performance adjusted prevalence was 33% (95%CI: 28-39%). Based on these estimates the range of infected people in this province would be between 518000 and 777000. Conclusion:The population seropositivity prevalence of COVID-19 virus infection indicated that the asymptomatic infection is much higher than the number of confirmed cases of COVID-19. This estimate can be used to better detect infection fatality rate and decide for public policy guidelines.

We determined the seroprevalence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in an affected area in northern Iran in April 2020. Antibodies to SARS-CoV-2 were detected in 528 persons by using rapid tests. Adjusted prevalence of SARS-CoV-2 seropositivity was 22.2% (95% CI 16.4%-28.5%).

Background: Addiction is a primary, chronic disease of brain reward, motivation, memory and the related circuitry. Objectives: The purpose of the study was the measurement of effective components in addiction relapse, in Rasht city of Guilan province, Iran. Patients and Methods: This study was done in 2014 that has been performed by using the factor analysis method. In the qualitative stage the process owners were 45 experts, and in the factor analysis stage they were 1850 people who were under treatment at addiction treatment centers. The data collection tool was a Researcher-Made Questionnaire whose content validity was determined through expert panel, and its construct validity was determined through exploratory factor analysis by principal component analysis method with varimax rotation using SPSS16 software. Results: In exploratory component analysis, 4 main components were identified; Individual factors with 6 variables, 25.72% variance, and 17.81 eigenvalue as the most important factor, and Economic factors with 5 variables and 7.64% variance as the less important factor, clarified the Addiction Relapse changes; however, in the fitted model which is the most completely saturated model, 4 factors of Individual factors with ß = 0.48, family factors with ß = 0.23, occupational factors with ß = 0.2, economic factors with ß = 0.12 had the highest predictive power in the order of importance. Conclusions: According to the findings, individual, familial, social, cultural, and economic factors were the most important in relation to the addiction relapse.

Background: Northern Iran counts as one of the highest prevalence regions for esophageal cancer (EC) worldwide. This study was designed to assess the epidemiologic aspects of EC in north central and northwest Iran over a 10 year period. Materials and Methods: The Guilan cancer registry study (GCRS) is a populationbased cancer registry study featuring retrospective (1996-2003) and prospective (2004-2005) phases. A detailed questionnaire based on WHO standards for cancer registratration was applied to gather the required information. Two trained physicians coded information using ICD-O-3 in close coordination with an expert pathologist. Results: A total of 19,936 cases of malignancy (mean age 55.4±18.0 years, range: 1-98 years) were registered, including 1,147 cases (670 males, 447 female; mean age: 64.0±11.5 years) of EC. In 1996 the male/female ratio among patients with EC was 1.25 which increased to 1.53 in 2005. The lower third of the esophagus still remained the most common site of tumors. The average age-standardized rate (ASR) was 6.9 and 4.1 per 10 5 men and women, respectively. In 1996, the ASRs were 7.2 and 5.2 per 10 5 men and women which decreased to 6.9 and 4.1 per 10 5 in 2004-2005. Squamous cell carcinoma (SCC) was the most prevalent histological subtype of EC accounting over 80% of cases. Conclusions: However the prevalence of adenocarcinoma (ADC) showed an increase to 18.4%. Guilan province may be considered a relatively low incidence region for EC.

Background: Hepatitis C is a major cause of liver failure and liver transplantation. The known risk factors of this disease include blood transfusion, injection drug use, high risk sexual behaviors, tattoos, and use of shared blades and syringes. Due to the higher risk of viral hepatitis among people in prison, this study was done to find the seroprevalence of hepatitis C virus (HCV) and associated risk factors in Lakan Prison in Rasht. Methods: Prisoners in Lakan Prison underwent a cross-sectional study in 2018. A questionnaire containing demographic information and risk factors was distributed to the inmates and they were asked complete them. High-risk individuals were selected and a blood sample was taken and tested. Data were collected and analyzed by SPSS18 software. Results: Out of 2215 prisoners, 1238 people had at least one risk factor, of whom 408 individuals were selected by random sampling. One hundred inmates were positive for anti-HCV antibody, yielding a prevalence of 24.5% (95% CI: 20.4%–28.7%) of whom 42.6% were people who injected drugs and 4 cases were found positive for the hepatitis B surface antigen, yielding a 1% prevalence (95% CI, 0.2%–2%.). A history of injecting drug use (OR 4.28, 95% CI: 2.55–7.17), and previous history of imprisonment (OR 2.94, 95% CI: 1.34–6.53) had association with HCV infection. Conclusion: The present study shows that hepatitis C is prevalent in prisons and preventive and screening programs should be implemented with necessary training for inmates.