hepatitis c virus ( hcv ) is an enveloped , single - stranded ribonucleic acid ( rna ) virus with positive polarity .
this virus is one of the most important pathogens of the human and is able to cause mild to severe liver diseases .
the virus is a member of the hepaciviruses genus in the flaviviridae family ( 1 ) .
hepatitis c virus infection is a major blood - borne infection worldwide , with a silent epidemiology , that it has reached pandemic proportions ( 2 ) .
the chronic infection with hcv , remains a troublesome health problem worldwide , which approximately 3% of the population suffering from it .
its prevalence is higher in some countries of asia and africa and approximately 14.5% in egypt ( 3 - 5 ) . in developing countries ,
the chronic hepatitis c is the most prominent cause of liver cirrhosis , hepatocellular carcinoma and liver transplantation ( 6 ) .
available estimates indicate that worldwide there were 54,000 deaths and 955,000 disability- adjusted lifeyears associated with acute hcv infection ( 4 ) .
the main routes of transmission in hcv are exposure to infected blood or blood product , intravenous drug use , infected medical equipment , tattooing , needle stick , hemodialysis , sexual activity and organ transplantation ( 2 , 3 , 5 ) .
the prevalence of anti - hcv from population - based studies is used to compare hcv infection levels globally .
hepatitis c virus infected an estimated 185 million people worldwide and is a significant cause of morbidity and mortality .
also , in developed countries , hcv predominantly infects people who inject drugs ( 9 ) .
peoples in some closed settings such as prisons , jails , juvenile detention facilities , pretrial detention centers , and extrajudicial detention centers for people who use drug showed higher prevalence of hcv ( 10 ) .
however , it seems that the prevalence of this virus in the general population of iran is less than 1% ( 11 ) , which is approximately lower than the reports of the neighbor countries .
the prevalence of hcv in the general population of different countries of the developed world around iran has been reported to be between 0.9 and 4% ( 11 ) .
there are no previous reports about the prevalence of hcv in rural population of iran and due to the differences in hcv - related risk factors between these two populations , performing of the study on the prevalence of hcv in the rural population is seriously needed .
this study was designed to determine the prevalence of anti - hcv antibody in general population of two villages , farmashkan and akbarabad , of the kavar city in fars province , iran , and evaluate the related risk factors in these areas . moreover ,
the possible associations between all risk factors with anti - hcv antibody prevalence were also evaluated in this population .
the present study is a part of kavar cohort study ( k.c.s ) , which is started from 2006 in kavar town with about 71856 populations .
this town is located in 35 kilometer southeast of shiraz , the capital of fars province , iran .
gastroenterohepatology and endocrine research centers affiliated to shiraz university of medical sciences are implementing k.c.s . from the start of k.c.s till now , all peoples are followed every two years . in the original cohort study ,
demographic and anthropometric characteristics of participants are documented in the questionnaire . in a cross - sectional study , which approved in ethical committee of shiraz university of medical sciences , by using cochran formula and assuming p = 0.03 , q = 0.97 , d = 0.01 and  = 0.95 , the sample size of 1049 was calculated .
performing of the study we used census method sampling and therefore , blood samples of all of the iranian peoples aged  7 years old in the two villages , farmashkan and akbarabad of the kavar city in fars province , iran , which referred to the k.c.s center were used .
our inclusion criteria were age equal or more than 7 years and using no medication for the hcv treatment .
demographic information included age , gender , marital status , occupation , history of blood and its product transfusion , hemodialysis , organ transplantation , dental procedure , accident , war injury , tattooing , injection drug use , addiction , alcohol use , personal or family history of liver disease , imprisonment , extramarital sexual contact , hepatitis b virus ( hbv ) vaccination , concomitant diseases and its symptoms were extracted from their medical records . the blood samples ( 10 ml )
were cooled on ice and taken to a specialized laboratory affiliated to gastroenterohepatology research center , shiraz university of medical sciences , shiraz , iran .
the blood samples were centrifuged at 3500 rpm for 15 min at 4c and the serum was separated and stored at -70c until further analysis .
the serum igg antibody against hcv was determined using a third - generation indirect enzyme immunoassay ( eia ) kit ( acon laboratories , inc , usa ) .
this test can detect various subtypes of hcv antibodies using the recombinant antigens specific for core , ns3 , ns4 and ns5 . the clinical sensitivity and specificity of this kit
data were reported as frequency and percentage and analyzed using spss software version 17.0 ( washington , usa ) for windows .
qualitative data were analyzed by chi - square and fisher s exact tests to find any association between risk factors and hcv - antibody positivity .
an independent samples t test was used to compare the age variable between the two villages .
data were reported as frequency and percentage and analyzed using spss software version 17.0 ( washington , usa ) for windows .
qualitative data were analyzed by chi - square and fisher s exact tests to find any association between risk factors and hcv - antibody positivity .
an independent samples t test was used to compare the age variable between the two villages . a p value < 0.05 was used to indicate a statistically significant difference .
a total of 6095 participants with age range of 88 years ( 7 - 95 years ) and mean  standard deviation of 34.58  17.29 years , including 2218 males ( 36.4% ) and 3877 females ( 63.6% ) were enrolled in this study .
a statistically significant difference was observed regarding the age of persons between the two villages ( 3393 and 2702 participants with age of 32.62  16.52 and 36.93  17.90 years from akbarabad and farmashkan , respectively , p < 0.001 ) .
age groups , marital status , jobs / positions and other historical information are presented in figure 1 .
most of our participants were in the age range of 21 - 35 years ( 33.5% ) , married ( 56.1% ) , and unemployed ( 51.9% ) and had the history of dental procedure .
overall , 15 out of the 6095 participants , 8 female and 7 male subjects , were anti - hcv positive ( 0.25% ) .
although , anti - hcv antibody prevalence was two in 1000 participants ; however , seroprevalence of hcv in children was four times greater than general population and was 1% .
frequency and percentage of the person s anti - hcv antibody status based on the age groups , marital status , jobs / position and related risk factors are presented in table 1 . among them , 12 persons were symptom - free and only 3 persons were afflicted with fatigue and mild anorexia .
one of them also had abdominal pain . despite the hbv vaccination , two children ( 13.3% ) had the concomitant hbs - ag positivity and hbc - ab negativity .  
comparisons of the effects of gender , marital status , age and history of blood transfusion , dental procedure , accident and imprisonment on the frequency of anti - hcv antibody are presented in table 2 .
only a significant relationship was detected between a history of blood transfusion and the prevalence of hcv ( p < 0.001 ) . also , persons with history of blood transfusion had 15-fold higher risk for anti - hcv positivity ( or : 15.54 , 95% ci : 4.89 - 49.41 ) .  
3393 and 2702 out of the 6095 participant were native of akbarabad and farmashkan with the age range of 83 and 88 years ( 7 - 90 and 7 - 95 years ) and the mean age of 32.62  16.52 and 36.93  17.90 years , respectively .
moreover , the prevalence of persons with positive anti - hcv antibody was 0.35 and 0.11% , respectively .
a statistical significant association was found between blood transfusion and anti - hcv antibody positivity in akbarabad village ( p < 0.001 ) .
our analysis also demonstrated that in the akbarabad village , those with the age  12 years old had three - fold higher risk for anti - hcv antibody positivity than other subjects ( or : 3.15 , 95% ci : 0.95 - 10.44 ) .
in addition , the individuals with a history of blood transfusion had 46-fold higher risk for anti - hcv antibody positivity than those with negative history of blood transfusion ( or : 46.41 , 95% ci : 11.18 - 192.72 ) .
no statistical association was found between the anti - hcv antibody positivity and evaluated variables except history of blood transfusion ( p < 0.001 ) in farmashkan villages ( p > 0.05 ) .
individuals with a history of blood transfusion had11-fold higher risk for anti - hcv antibody positivity than those with negative history of blood transfusion ( or : 11.40 , 95% ci : 1.02 - 127.21 ) .
this study calculated the prevalence of hcv infection in the general population of the two kavar villages , akbarabad and farmashkan , and assessed its association with gender , age , marital status , jobs / position and history of some related risk factors .
our participants were rural general populations and most of them were without any known hcv - related risk factors .
the general prevalence of hcv in this study was detected as 0.25% and the highest prevalence was seen in age  12 years old ( 1% ) .
although there was a significant association between blood transfusion and anti - hcv antibody positivity , no significant associations were detected between other related risk factors and anti - hcv positivity .
based on a systematic review in 2009 , hcv infection prevalence in general population was calculated as 1.6% ( 3 ) that is much higher that our results . in another study , which performed in the civilian population of the united states
, it had been demonstrated that the prevalence of anti - hcv in the united sates decreased from 1.9% in 2001to 1.3% in 2005 , and remained stable up to 2010 ( 12 ) .
the total viremic hcv population of australia in 2012 was estimated at 230000 with a viremic prevalence rate of 1.0% .
in addition , the anti - hcv prevalence was estimated at 1.3% , equivalent to 308000 anti - hcv positive individuals ( 13 ) .
ferthermore , several studies were performed about the prevalence of hcv in the european , american , african and asian countries . in a study from austria in 2008 , the anti - hcv prevalence rate of 0.5% ( 0.10.7% )
different low ( 0.12% ) and high ( 1.23% ) prevalence rates were reported in two studies performed in 2007 ( 15 ) and 2012 ( 13 ) , respectively .
total seroprevalence of 1.38 , 0.96 , 0.6,0.63 , 12.5 , 0.4 , 0.5 , 2.6 , 1.6 and 0.95 % in brazil ( 16 ) , canada ( 17 ) , czech republic ( 18 ) , denmark ( 19 ) , egypt ( 20 ) , england ( 21 ) , germany ( 22),spain ( 23 ) , switzerland ( 24 ) and turkey ( 25 ) , were also recorded , respectively .
our detected hcv prevalence is lower than all previous reports and approximately near to the reports from england and germany . also , our prevalence is similar to a recently report from mashhad , iran . in that study ,
the prevalence of hepatitis c seropositivity in the general population of mashhad , northeast of iran , was evaluated and its results demonstrated that the overall seroprevalence of hepatitis c was 0.2% using the elisa method ( 1 ) .
reported that the hcv prevalence in iran is 0.5% in individuals with age range of 18 - 65 years and higher and about 1% was seen in male ( 26 ) .
the probable reason for this difference may be the nature of two population , the urban population in merat et al . ( 26 ) and shakeri et al . ( 1 ) studies and the rural population in our study . therefore , the hcv infection related risk factors and consequently anti - hcv antibody prevalence were lower in this study .
however , the hcv viral load evaluation using rt - pcr is highly recommended to confirm this difference .
although , the prevalence of hcv infection in children ranges from 0.05 to 0.4% ( 27 ) , the higher prevalence was seen in this study for the persons with age of  12 years old ( 1% ) .
it is necessary to evaluate the hcv antibody of both children and their mothers to rule out the vertical transmission of hcv . in our study ,
similar to previous reports from iran ( 1 , 26 ) , the hcv - positive male was dominant in comparison to female ( 0.3% vs. 0.2% , respectively ) .
however , this difference was not significant and therefore there was no association between gender and anti - hcv antibody positivity . in an iranian study performed by kohan et al . in 2006 , 11.1% of hcv infected persons ( 23 out of 207 ) co - infected with hbv ( 28 ) . in our study , the hbv - hcv co - infection was detected in 13.3% of the persons ( two out of 15 ) .
also , the high anti - hcv antibody positivity was detected in the student groups ( 24.8% ) based on the job / position categorization .
this can be a warning for education and health ministry for learning mostly about viral hepatitis transmission routes and prevention , especially hbv and hcv .
transfusion of the infected blood and blood product is one of the major routes of the hcv infection .
this is more important in some populations such as thalassemia , hemophilia , and hemodialysis because they are dependent on the blood products during their lifetime .
it has been demonstrated that the hcv infection rate in these groups is higher than the normal population ( 29 - 40 ) as demonstrated in our study .
our study suffered from some limitations including limitations in the univariate analysis and some limitations related to the effects of a long - time of the cross - sectional study .
also , lack of confirmation of the positive anti - hcv antibody samples with molecular methods , such as pcr and rt - pcr is another limitation .
however , this issue is being set up and performed in our center for larger cohort study . in conclusion ,
due to this fact that hcv infection is a preventable and curable disease , we recommend more attention for the control of patient - to - patient hcv transmission in hospitals .
although prevalence rate in this study was lower than other studies and no statistical significant associations were found with common risk factors except blood transfusion , paying the especial attention to the all risk factors is seriously advised .
finally , further studies are required in other rural and urban populations for better evaluation of the hcv - infection prevalence and real source of transmission .
 background : hepatitis c virus ( hcv ) infection is a major blood - borne infection with silent epidemic , major global public health problem and diverse prevalence worldwide.objectives:this study aimed to evaluate the prevalence of hcv infection and related risk factors in the general population of two villages , farmashkan and akbarabad , of the kavar city in fars province , iran.patients and methods : a 34-month cross - sectional study was performed on all people of the villages aged  7 years from july 2007 to april 2010 . demographic information and history of hcv - related risk factors 
 were extracted from their medical records . for each participant , 
 the serum anti - hcv igg was assessed by the commercial enzyme - linked immunosorbent assay ( elisa ) kits.results:a total of 6095 participants ( 36.4% male and 65.6% female ) with the mean age of 92 ( 7 - 95 ) and mean  sd of 34.6  17.3 years were included in this study . 
 fifteen persons ( 0.24% ) were detected as hcv - positive and the highest prevalence was seen in age  12 years old ( 1% ) . 
 a significant association was only detected between blood transfusion and hcv infection ; therefore , those persons with history of blood transfusion had 15-fold higher risk for hcv seropositivity ( odds ratio 15.54 , 95% ci = 4.89 - 49.41).conclusions : our reported rate of hcv seropositivity is similar to the previous iranian reports 
 . however , future evaluations should be focused on the polymerase chain reaction method for the detection of hcv and determining and evaluating of other related risk factors . moreover , more attention should be paid to blood donors as a reservoir population of hcv . 
1. Background
2. Objectives
3. Patients and Methods
3.1. Statistical Analysis
4. Results
5. Discussion