Ninh Binh province, with a population of about 930,000 people, does not yet have an epidemiological investigation or comprehensive study of HCV.

Abstract
Background: Hepatitis C virus (HCV) is the most common viral infection among injecting drug users worldwide. The purpose of our research is to identify the real situation of HCV infection, knowledge and practice of hepatitis C prevention and identifies a number of factors related to risk behaviors higher HCV transmission in humans addiction treatment opiate methadone in Ninh Binh Province, Viet Nam.

Methods: By methods described cross-sectional analysis of 274 people on substitution treatment of opioid addiction with methadone at 4 district, Ninh Binh province, Vietnam in 2016.

Results: The author showed that: hepatitis C virus (HCV) infection rate is 62,7%, the subjects know all three routes of HCV infection accounted for only 51,1 %, Knowledge about blood route prophylaxis (81,4%) and safe sex (75,5%), other prevention accounted for 24,5% - 44,5%. Practices of HCV prevention and control: In the previous month(s) methadone maintenance treatment (MMT) was still 49,3% sharing needles and syringes (condom users) regularly having sex with sex workers (FSW) accounted for 70,6%, with casual partners, ranging from 23% to 24,6%. Especially when they had sex with more than one person at the same time, the condom used rate is only 2.0%. Study subjects have higher rates of hepatitis C virus (HCV) infection in groups: age of 30 years old and older unmarried group, sex group with non-spouses/partners, especially sex workers, with p<0,05. Patients with MMT tended to be in groups with longer methadone with an increased in incidence of HCV infection. Groups of high-risk behavior for HCV infection were: those who lacked of knowledge and practice, the group using synthetic drugs, with p<0,05.

Conclusion: The prevalence of Hepatitis C infection in the study population is relatively high, equivalent to many scientific publication. Knowledge and practice of preventing hepatitis C virus is still limited. Groups of high-risk behaviors that infect Hepatitis C viruses are: those who do not have access to knowledge and practice, the group using synthetic drugs.

Keywords: Hepatitis C virus infection, knowledge, practice, prevention, related, high risk factors, drug use, injecting drug use, synthetic drugs, treatment for opioid substitution, methadone maintenance treatment (MMT), having sex with more than one persion at a time, Ninh Binh Province, Vietnam.

Introduction
Hepatitis C is one of the major causes of liver disease worldwide. Hepatitis C virus (HCV) varies by country, region and HCV gene type distribution. The natural progress of hepatitis C is varied, and it can manifest slowly or quickly; in addition to the viral elements, genetic factors of the patient, environmental conditions also affect the natural course of the individual patient [11,26].

Worldwide, the number of people infected by HCV is estimated at 170 million (equivalent to 3% of the population). Frequency of infection varies by country and territory. Vietnam has not yet published any systematic investigation into the epidemiology of HCV infection [3]. The published data from various authors based on non-representative, and mostly limited, studies have resulted in very high HCV prevalence ranging from 0,6% to 6.1%. According to the World Health Organization (WHO), based on many sources, the prevalence of HCV infection in Vietnam is <6.1%.

Ninh Binh province, with a population of about 930,000 people, does not yet have an epidemiological investigation or comprehensive study of HCV. The province now has 1,780 drug addicts managed, with an estimated 2,500 people in practice. In terms of the epidemiological characteristics of hepatitis C, the route of transmission is similar to HIV but varies in degree of transmission; hepatitis C is often silent, difficult to diagnose and control, treatment protocols and preventive measures have not yet been taken into consideration, so the prevalence of HCV infection tends to increase, especially in group of injecting drug users.

To determine the current status of knowledge, practice and identify some related factors of methadone users in the district level facilities in Ninh Binh Province, in 2016, we advance the study aimed at two objectives: (i) To describe the status of infection and knowledge and practice on prevention of hepatitis C virus infection among MMT administrators in 4 districts/cities of Ninh Binh province 2016. (ii) Identification of factors related to the high risk behavior of HCV infection in the study population.

Materials and Methods
Study subjects
Files and records of patients receiving MMT in 4 methadone substitution clinics in the district of Ninh Binh province. Patients who are currently on MMT at the above-mentioned establishments, who are aged of 18 years old and over, voluntarily participate in the study. The representatives of the organizations, departments, organizations in the community of study areas: Director Health Center District (Head basis MMT), the leader of the district police in charge of the prevention of drug Party secretary, village chief, women cadre, youth union, farmer association, veteran association, population.

Methods

The method used for this study is: an analytical cross-sectional descriptive study, combining quantitative and qualitative data from different researches. Quantitative research sample size is calculated according to the following formula:

Inside:
α: acceptable confidence interval, α = 5%.

Z: confidence limit factor (1.96).

P: prevalence of HCV infection among people taking methadone treatment at the Ninh Binh HIV/AIDS Center, 2015 = 76.3% [2].

d: the possible variation of the rate, d=0.05 (desired precision).

Calculate n = 280. In fact, we investigated the total number of patients treated in the 4 research institutions in the number of 274.

Statistical analysis
Import data using Epidata 3.1 software. Analysis of the data processing method according to medical statistics by SPSS 18.0. Comparisons of the percentages of the study by the test 2, T-test.

Data are expressed in percentage, OR, 95% confidence interval (CI95%), p value

Results
Hepatitis C virus infection
Prevalence of some infectious diseases in pre-methadone maintenance treatment patients: HIV prevalence was high, accounting for 62.7%; HIV prevalence was lower, accounting for only 15.4% and HBV infection rate was 8.9%.

Table 1. Distribution of study subjects infected by HCV according to treatment facilities, education and marriage (n = 271)

The subjects with the lowest rates of HCV infection were Hoa Lu (24.7%), Tam Diep (73.2%) and Nho Quan (71.3%), the difference in Hoa Lu with other facilities was statistically significant, with p <0.01.

According to education, the illiterate population (66.7%) and the group with vocational education or higher (80%) had a higher prevalence of HCV infection, the difference was insignificant, with p>0.05.

Marital status, in addition to the group living with the spouse, had the lowest prevalence of HCV infection (58.5%), and other groups had a higher prevalence of HCV infection (63.6%-73.9%). For spawned groups, the prevalence of HCV infection was lower than that of the unmarried group and the difference was statistically significant, with p<0.05.

Table 2. Distribution of subjects with a new positive HCV antibody test over the duration of methadone treatment (n=91)

Number of subjects treated by methadone got very small proportion of HCV infection during treatment (from 2.5% - 2.9%). This rate did not appear in the MMT group after 18 months or more. The new HCV infection rate for the whole study population was 2.2%.

Knowledge about preventing the infections of hepatitis C virus

Table 3. Knowledge about preventing the infections of hepatitis C virus (n=274)

Subjects about knowledge of HCV transmission rates range from 55.1% to 81%. The number of subjects, which mentioned to all three routes of HCV infection accounted for only 51.1%, in other words, they knew only about half of them. The prevalence of HCV non-communicable transmission was relatively low, ranging from 42.3% to 64.6%. Knowledge of how the study subjects with HCV infection prophylaxis in prevention of high blood stream was 81.4% and road safety sex was 75.5%. Other reserves have a lower understanding rate, accounting for 24.5% - 44.5%. Object of study is not concerned about the developments and the consequences of HCV infection problem. Those who know about the progress and consequences of HCV infection are relatively low, ranging from 48.5% to 60.9%.

Practice on the prevention of infection with hepatitis C virus

Table 4. Practice on the prevention of infection with hepatitis C virus

 

Subjects in the previous month MMT shows that still almost half (49.3%) of them shared needles when injecting drug users, but prevalence decreased rapidly after 12 months of MMT and no longer sharing needles at the next time. Subjects in the past 12 months shows that the number of people having sex with their wives or lovers was at the highest point (84.7%), then with FSWs was 37.6%, with more than one person at a time accounted for 18.2% and with casual sex accounts for the lowest rate (15.3%). Subjects when having sex with FSWs, they often use condoms, the ratio is the highest, accounting for 70.6%. When having sex with his wife, lover, or mistress, the rate of using condoms is about 23% - 24.6%. Especially when they have sex with more than one person at a time they usually do not use condoms, the condom used rate only 2.0%.

Some factors related to HCV infection rates and high risk factors of HCV infection

Table 5. Some factors related to the prevalence of HCV

The subjects in the group age of 30 years old and older had a higher prevalence of HCV infection than the group age under 30 years, the difference was statistically significant, with OR = 2.10 (CI95%: 1.00-4.15) and p<0.05.

Group study subjects did not live with his wife/husband, had higher HCV prevalence, differences were statistically significant, with OR = 1.79 (CI95%: 1.03- 3.10) and p<0.05.

Group sex with prostitutes had a higher prevalence of HCV than other group, the difference was statistically significant, with OR = 1.87 (CI95%: 1.10-3.17) and p<0,01.

Special group sex with more than one person at a time had a higher prevalence of HCV than other group, the difference was statistically significant, with OR = 5.53 (CI95%: 2.26-13.51) and p<0.001.

Group objects to achieve knowledge prevention of HCV prevalence of HCV was lower than other groups. However, the difference was not statistically significant, with p>0.05.

Group objects to achieve practical prevention of HCV prevalence was lower than the other group, the difference was statistically significant, with OR = 0.34 (CI95%: 0.20-0.56) and p<0,01.

Table 6. Synthetic drug use related with more than one person who have sex at a time during MMT

Groups of synthetic drug used at different times during MMT have sex ratios with more than one person at a time was higher than the group not using synthetic drugs. The difference was statistically significant, with p<0.001. Especially at 12 months after MMT, this rate reached the highest point (74.2%), with OR = 52.16 (CI95%: 17.24-157.86).

Table 7. Use of synthetic drugs related to HCV prevention practices of study subjects

Groups of synthetic drug used at different times during MMT achieved in practice proportion prevention of HCV were lower than the non-use of synthetic drugs. The difference was statistically significant, with p<0.01.

Table 8. Knowledge and practice of study subjects related to the use of shared needles at the time of 1 month before MMT (n=274)

Group achieved knowledge prevention HCV utilization rate sharing needles when injecting drugs at the time of 1 month before MMT was lower than other groups, but the difference was not statistically significant, with p>0.05.

Group achieved in practice prevention HCV utilization rate sharing needles when injecting drugs at the time of 1 month before MMT was lower than other groups, the difference was statistically significant, with OR = 0.28 (CI95%: 0.17-0.46) and p<0.01.

Discussion
There is no vaccine against HCV and it unlikely shows that HCV vaccines will be available in the near future. Therefore, the current prevention of HCV is prevention of HCV’s infection in community. In Vietnam, when analyzing 13 risk factors, which were identified as: blood transfusions, sex with injecting drug users and injecting drug use. Intravenous drug use is the greatest risk of acquiring HCV infection today. This group has the highest HCV prevalence (up to 100%) according to data from both national and international studies. The program provides needles and syringes that do not deliver the expected results [14]. Therefore, prevention of drug used in general and group or individual education should be strengthened. On the other hand, it is necessary to integrate drug prevention programs together with preventing the spread of HIV, HCV and HBV because they have the same transmission path and hope to be able to save and bring higher efficiency due to the object of interest. According to the European Center for Prevention and Management of Illness (2015), studies on HIV, HBV and HCV infection in Latvia, have studied and proposed important actions for strengthening the response to HIV, HBV and HCV, which focuses on three topics: reducing the harm of drug users, testing and vertical infections; Offers 14 recommendations for the management and mitigation of HIV, HBV and HCV-related illnesses [4], [12], [20], [24].According to Jager J., et al., Studies on hepatitis C and injecting drug use (IDUs), concluded that infectious diseases such as hepatitis A, B, C, and HIV are important health outcomes caused by drug addiction, especially among IDUs [6]. According to a study by Jarlais D. et al. (2005), Reducing hepatitis C virus infection and HIV infection among IDUs in New York City from 1990-2001, the results showed tat with the new needle change solution for the period of 1990-2001, the incidence of HIV infection decreased from 54% to 13%, and HCV prevalence dropped from 80% to 59% [7]. Javanbakht M., et al. (2014) studied the high rates of illicit drug use in Iran and the effectiveness of opiate addiction treatment with methadone in the prevention of HCV infection, it is necessary to develop MMT centers at regional and national levels [8]. The results of the thesis showed that the prevalence of HCV infection among subjects was relatively high at 62.7%. Among them, HIV prevalence (15.4%) and HBV (8.9%) were stable and low. According to a study by Kayser BB (1997), a study on the prevalence of HIV, HBV and HCV among a group of MMT clients in Geneva showed that HCV prevalence among IDUs was also high at 50- 86%, HCV infection occured most often during the first 4 years of drug use [9]. According to Kresina T.F., et al. (2014) also reported 60-80% of HCV infections in injecting drug users worldwide [10]. According to Novick D.M. (2000), study in the United States on MMT, the prevalence of HCV infection was 64% -84% [17]. According to research by Ramezeni A., et al. (2014) in Iran, the prevalence of HCV infection was 56%, HIV was 19% and HBV was 6% [19]. According to Wang C., et al. (2016), study in China, at the time of MMT, HCV prevalence was 66.8% in 2005 and 45.9% in 2012; After 6 months of MMT, HCV prevalence was 30.4% (2004) and 93.1% (2012); The author estimates that HCV prevalence remains alarmingly high among clients treating MMT in China. A comprehensive preventive strategy is needed to control the HCV outbreak among clients treating MMT in China [25]. According to Hoa Dinh-Van et al (2007), the prevalence of HCV infection among drug users was 35.1% [5]. According to a study by Manh Nguyen-Dang (2007), this rate was 64.41%, the risk increased with addiction time, there was a strong correlation between IDU and hepatitis C, with p<0.001 [13]. According to Trung Ho-Quang (2012-2013), a study in Phu Tho province among IDUs treated with methadone, the prevalence of HCV infection was 47.8% [22]. According to Trinh Luyen-Van (2016), in Nghe An, the prevalence of HCV infection was 65.2% [21]. According to Van Cao-Kim et al. (2010), research in Ho Chi Minh City, the prevalence of HCV infection was 42.5% [23]. In terms of marital status, the lowest prevalence of HCV infection (58.5%) was in the cohabiting group and the other group had a higher prevalence of HCV infection (63.6%-73.9%). Particularly for the group living with their spouse, the prevalence of HCV infection was lower than that of the unmarried group and the difference was statistically significant, with p<0.05. In modern society, the general trend is that sex is usually earlier than sex. On the other hand, young people are more likely to use synthetic drugs and soon after, the consequences after using synthetic drugs often increase their need for having sex without using condoms... these are also the reason for the high incidence of HCV infection is through unsafe sex. The number of patients in MMT has a very small incidence of HCV infection during MTT (2.5%-2.9%). This rate does not appear in the MMT group age after 18 months or more. According to Nolan S., et al. (2014), the study of the effect of MMT treatment on the incidence of hepatitis C among illicit drug users in Canada showed that: MMT therapy seems to be highly protective against the incidence of hepatitis C among illicit drug users [16]. According to Canh Hoang-Dinh, after 12 months of MMT, the prevalence of HCV infection increased by 0.5%, lower than the results of this study (2.9%), after 24 months increased to 2.4%, higher than results in the study (0%) [1].

Patients with knowledge of HCV transmission rates range from 55.1% to 81%. The number of subjects who knew all three routes of HCV infection accounted for 51.1%. The prevalence of HCV non-communicable transmission was low, ranging from 42.3% to 64.6%. Patient is knowledge of how to prevent HCV infection was high in prevention of blood route (81.4%) and safe sex (75.5%). Other reserves have a lower understanding rate, accounting for 24.5%-44.5%. They have not paid much attention to the evolution and consequences of HCV infection. They know about the course and the consequences of the HCV infection rate relatively low, ranging from 48.5% to 60.9%. According to Trinh Luyen-Van, the percentage of people with right knowledge about the cause of viral hepatitis and prevention of disease accounts for 65% to 75% [21]. People in the MMT group said that: "Most of them do not know anything about hepatitis C virus, hepatitis C virus (including hepatitis B virus). The report had hepatitis C and was also largely unprotected from knowledge about hepatitis C, and some knew little about hepatitis C. But they thought the disease with HIV/AIDS, people know the way of transmission clearly, the way to prevent but the lack of drugs they have the need to use any accept and be prepared for unsafe acts such as sharing needles and syringes. The head of the MMT facility at the research facility said: "There is little interest in HCV infection in most settings, they only care about HIV/AIDS patient information and communication. Then there is a slight interest in hepatitis B, and when they are tested for methadone prior to methadone treatment, they have counseling for all three HIV diseases. MMT patients are also less likely to be concerned with hepatitis C. If they are aware of this disease, most patients will not have adequate information and they do not think HCV infection is worrying".

Nearly half (49.3%) of them shared needles and syringes while IDUs, but this rate declined rapidly after 12 months of MMT and no longer sharing needles at the next time. According to a study by Mlunde L.B., et al. (2016), in Tanzania, the share of needles for injecting drug users was 14.2% [15].  According to Kresina T. F., et al, the use and abuse of drugs and alcohol are important considerations in HCV/HIV co-infection. Both groups are at high risk for sexual behavior and IDU that provide for the widespread transmission of HIV and HCV, drug and alcohol users are important factors in promoting high-risk sex as well as increasing the number of sexual partners [10]. Subjects who have sex with FSWs often use condoms, accounting for 70.6%. When having sex with his wife, lover, casual sex partner, the rate of using condoms is about 23%-26.8%. Especially when they have sex with more than one person at a time they usually do not use condoms, condom use only accounts for 2.0%. In Tanzania, sexual partners with partners, only 17.4% use condoms [15]. The MMT group said, "When they first started using opiate, they usually had sex with a prostitute or a sex partner, but when they used opium for a long time, there is very little need for sex because only pay attention to money and drugs "; "When they use synthetic drugs, they usually use it in groups and often both men and women join in. After using synthetic drugs, they often have a desire for collective sex and rarely do, little use of condoms. They change their relationship with the number of women in the group, usually not having sex with men". According to research by Phuong Nguyen-Thi and Hien Ho-Thi (2011) on FSWs using amphetamine stimulants in Hanoi, the amphetamine use rate was quite high. When subjects use amphetamines, they often lose control of behavior and unsafe sex [18].

Results showed that subjects in the age group of 30 years or older had a higher prevalence of HCV infection than those under 30 years of age (64.7% and 46.7%), the difference was statistically significant, with OR = 2.10 (CI95%: 1.03-4.15) and p<0.05. This result is also consistent with some domestic and foreign publications. In general, the prevalence of hepatitis, hepatitis C in particular is related to higher life expectancy, and the longer the drug use, the higher the incidence. The subject group is living with wife/husband, prevalence of HCV is lower than the other group, and the difference was statistically significant, with p <0.05 Often, when the subjects are not married or separated, divorced or widowed, they fall into the category of high risk behaviors that infect HIV/AIDS, HBV infection, HCV and sexually transmitted diseases. Sexual contact with other subjects has a high prevalence of HCV infection. Especially group sex with more than one person at a time had a higher prevalence of HCV infection than those of the other group (88% and 57%), with OR = 5.53 (CI95%: 2.26-13.51) and p<0.001. Through research results, we can also put a "?" for the increase in the prevalence of HCV infection in the study population, it is possible to have sex with many people, especially with more than one person at a time when it is commonly said that the "herd" relationship after use of synthetic drugs, drugs is also one of the reasons for the increase in HCV prevalence. Compulsive drug users tend to be in groups with longer doses of methadone with an increased incidence in HCV infection. The difference was statistically significant in the methadone group after 12 months, with p<0.05. In summary, the results of the study showed that high-risk behaviors were associated with high HCV prevalence. In addition to sharing needles and syringes in injecting drug use, it has been proven, however, that the reasons for having sex with more than one person at one time are also being considered to increase the prevalence of HCV infection.

The users of synthetic drugs at different times in the course of MMT have sex ratios with more than one person at a time higher than the group not using synthetic drugs. The difference was statistically significant, with p<0.001. Those who used synthetic drugs at different times during MMT had a lower rate of HCV prevention than those who did not. The difference was statistically significant, with p<0.01. According to the MMT group, "When they are addicted to drugs, it is time to add to the deficiency in the body, despite the risky behavior of blood diseases, and they are ready to share needles and syringes when injecting drugs, when they have used synthetic drugs, often after having sex and having sex without condoms".

Conclusion
The study results showed that the rate of HCV infection of the methadone treatment at study sites is relatively high, similar to many scientific publications in the country and the world, the rate of HCV infection tends to increase not been no cover. Knowledge and practice of prevention of HCV infection of subjects is low, potentially leading to the risk of HCV infection. In addition to the proven evidence of HCV infection, it appears that the use of synthetic drugs appears to be one of the culprits of high-risk behaviors that infect HCV. The results of our study have implications for the use of synthetic drugs and sexual intercourse with more than one person at a time and with higher prevalence of HCV infection in this group.

Dung Do-Van¹, Hien Luong-Xuan², Dung Dao-Van³, Hanh Hoang-Thi-Hong⁴.

¹The Union of Science and Technology Association of Ninh Binh province

²Thai Binh University of Medicine and Pharmacy

³Central Propaganda Department

⁴Health service centre of Ninh Binh province

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