This study is the first national-level study in Rwanda to assess risk factors for HCV using the country’s seroprevalence survey for HCV exposure (HCVAb). The national-level coverage and large sample size contribute to the strength of our findings. To our knowledge this is the first study to assess risk factors associated with HCVAb prevalence in a nationally-representative screening program for members of the general population in SSA.
Compared to previous studies conducted in Rwanda among PLHIV and pregnant women that produced prevalence estimates of 4.6% and 2.6% respectively9,10, the HCVAb seroprevalence estimated by this study is 6.8%. The likely explanation for this higher prevalence is the strategic decision by the campaign to target older individuals and the self-selected nature of voluntary participants where individuals who had reason to suspect that they had viral hepatitis may have come forward for testing. Factors associated with being HCVAb positive following adjusted analysis included older age with 0.1% of risk of developing HCV every year for each participant, lower socioeconomic status, geographic variation, family history of HCV and exposures to traditional surgical operations. Associations between HCV infection and both family history of HCV and exposures to traditional surgical operations remained significant after adjusting for age.
Traditional scarifications and operations, though heavily discouraged, are still widely prevalent in informal healthcare practices in Rwanda. Although data on frequency of traditional surgical practices in Rwanda is limited, the Rwanda Demographic Health Survey 2015 reported that 8.5% of circumcisions for people between 15-59 years old were performed by traditional practitioners or a family friend 17. Collectively, these findings suggest a need for interventions targeted to traditional healers such as increasing population awareness on the risks of traditional cuttings for infectious disease transmission. The Ministry of Health and RBC strongly advise individuals in Rwanda to seek health advice from official health facilities rather than traditional healers. Our findings add further evidence to the potential harm of unregulated traditional practices.
Although the most frequently discussed transmission routes for HCV are parenteral, there has also been much debate on the impact of household exposure on HCV transmission18. Our study found an association between familial history of viral hepatitis and HCVAb prevalence. Previous observational studies have reported clustering of cases within households and documented evidence of higher disease prevalence among individuals with an infected family member compared to the general population19–22. Moreover, a recent cross-sectional survey of HCV patients conducted in China showed that long term exposure to an infected family member was associated with infection23, an indication that a constant exposure to low-risk transmission routes such as razors, tooth brushes and nail clippers could still contribute to infection. However, another plausible explanation for our findings is that members of the same household could be exposed to the same external risk factors. For example, family members visiting the same traditional medicine practitioner with unsafe needle practices may have an elevated risk for infection. Given low awareness among the population on potential risk of transmission of HCV within households, patients with HCV should be counselled on prevention of disease transmission to their cohabitants. Cohabitants should be offered the option of receiving HCV counseling and undergoing HCV testing.
Similar to other studies conducted in Rwanda on people living with HIV and on pregnant women9,10, older age showed strong associations with HCVAb with a trend of higher odds of infection with increasing age group (Figure 1). It is likely that older individuals are more likely to have historical exposure to risk factors such as unhygienic medical procedures and scarifications, either within a health facility or with traditional practitioners, prior to implementation of current infection control policies.
Co-morbidities that showed associations with HCVAb prevalence were HBP and CRF. According a large household survey in Rwanda, 33.2% of people aged 55-64 years old had high blood pressure while 6.7% of people between 25-34 years old had high blood pressure24. There might be interaction between co-morbidities and age (see table 3). CRF could be a complication of chronic HCV and HCV can be acquired during different procedures performed by health care providers during management of CRF, such as dialysis 25. Self-reported HIV infection was associated with HCVAb prevalence and can be explained by potential shared modes of transmission between HIV and HCV.
Individuals in socioeconomic category of Ubudehe category 3 have lower odds of HCVAb compared to individuals in the lowest socioeconomic category of Ubuduhe category 1. Individuals using RAMA as health insurance compared to those using Mutuelle also have lower odds of infection. Individuals from lower socioeconomic categories may be at a higher risk for HCV due to more exposures to unhygienic practices in informal health settings or sharing of sharps such as razors.
This study also found that people from the Northern province have lower Seroprevalence for HCV compared to other provinces. This may be due to the fact that other provinces have higher migration across borders and a greater refugee population. Apart from socio-economic status, other unmeasured cultural practices or risk factors could have contributed to these geographical differences10,11,13,23,26.
Several limitations were identified. The demographic profile of the sample population of voluntary participants differed from the Rwandan population at large, with a substantially greater proportion of females (69%) and a higher median age (43.0) than the general population. Thus, the prevalence estimate and risk factors found to be associated with HCVAb may not be generalizable to the entire population. Since children are less likely to be infected with HCV, the prevalence of HCV in Rwanda is likely lower than reported in this study. As this study utilized presence of anti-HCV antibody as the primary marker of HCV infection, the risk factors identified are relevant for present or previous HCV infection and may not be associated with chronic viremic state. Other unmeasured risk factors such as exposure to mass casualties through war and conflict, sexual violence, refugee status, occupational risk like health care providers or community based traditional practices may have been more prevalent historically. Key populations, such as injection drug users and men who have sex with men, were not specifically identified or characterized in this study, though the proportion of individuals with these risk factors have been previously reported to be low in the Rwandan general population27. Lastly, this study relied on routinely collected data and self-report to assess clinical variables (e.g. HIV status) or historical exposure which may have led to misclassification. Participants are likely to have underreported at random with respect to the outcome due to poor recall of historical events. If a true association exists between HCV infection and variables identified in this study, then random misclassification of exposures would have led odds ratio towards the null. If exposures were recorded accurately, we would expect to obtain the true effect of the known risk factors on HCVAb. Also plausible is that individuals with lower health literacy had lower awareness of risk factors. These individuals could have had either higher risk for HCV infection due to more exposures to less hygienic health practices or lower risk for HCV due to less healthcare-seeking overall.