Prevalence of viral and non-viral hepatitis in Menoua Division, West Region, Cameroon: a retrospective hospital-based study

Introduction The paucity of data on hepatitis' epidemiology in Menoua Division, west region, Cameroon, prompted us to assess the prevalence of viral and non-viral hepatitis in this area. Methods A retrospective exhaustive study based on records of patients from January 2008 to June 2014 was conducted in 9 health centres in Menoua Division. Targeted subjects were patients who did not receive hepatitis vaccines for the past year and have been screened for hepatitis B virus (HBV), hepatitis C virus (HCV) and/or a blood transaminase. Associations between variables were quantified with odd ratios (OR) and 95% confidence interval (CI). Cochran-Armitage test of linear trend was used for testing proportions of ordinal variables. Fisher's exact test was used for testing the association between 2 qualitative variables when expected counts were less than 5. Results The overall prevalence were 9.6% and 6.7% for HBV and HCV respectively. HBV mostly infected people aged 21-30 (12.4%) while the prevalence of HCV increased with age up to 35.4% (p=0.03). A 0.6% co-infection was observed. Thirty percent of positive HBV or HCV had high transaminase while 13% of patients with elevated transaminase showed negative viral serology. Conclusion These results show that hospital-based prevalence of HCV and HBV in Menoua Division is under the Cameroon's national range but point out the fact that non-viral hepatitis might be a serious case of concern in this area. There is therefore, a need to identify the risk-factors of non-viral hepatitis.


Introduction
Hepatitis is a medical condition defined as inflammation of the liver and characterized by the presence of inflammatory cells in the liver parenchyma. There are several forms of hepatitis including viral, autoimmune [1], fatty liver [2], alcoholic [3], drug-induced- [4] and toxin-induced-hepatitis. It is assumed that most cases of hepatitis are due to viral infections [5] worldwide. As such, five classes of viral hepatitis (A, B, C, D and E) are described based on their transmission routes, incubation period, and evolutionary pattern of each virus [6].
According to the World Health Organization [7] approximately 325 million people were living with chronic hepatitis infections (HBV or HCV) worldwide in 2015. It is estimated that 257 million people are living with hepatitis B virus infection while 71 million people have chronic hepatitis C infection. Africa has the highest prevalence of HCV, rated to 5.3% [8] and Cameroon is the second most afflicted with a prevalence of (4.9-13.8%) after Egypt (4.4-15.0%) [9]. Last epidemiology studies in Cameroon showed a prevalence of HBV of  Associations were quantified using Odd ratios (OR) and 95% confidence interval (CI). Cochran-Armitage test of linear trend was used for testing proportions for ordinal variables. Fisher's Exact Test was used for testing association between 2 qualitative variables when expected counts were less than 5. P-values less than 5% were considered statistically significant.

Results
Among the patients screened for hepatitis or transaminases, 5337 fulfilled the inclusive conditions and did not fall under exclusive ones. of HCV was 6.7% with no significant difference (p = 0.78) between male (6.6%) and female (6.9%) ( Table 1).

Prevalence of viral hepatitis B and C according to Sub-
division: out of the 6 Sub-divisions, Santchou and Dschang were the most affected with an overall prevalence of 10.5 and 9.9% respectively for HBV, while the highest prevalence of HCV was in Santchou (13.3%) ( Table 4).  (Table 5).

Discussion
This study aimed to assess the prevalence of viral and non-viral hepatitis in Menoua Division. It was found that the number of patients screened significantly increased with time between 2008 and 2014.
This shows the increasing awareness of hepatitis in the general population. Furthermore, governmental policy has improved the availability of diagnostic tools which could also explain the increasing number of patients screened. Out of 5337 patients screened, 9.6% and 6.7% were infected respectively with HBV and HCV. The HBV prevalence of 9.6% obtained here is similar to the 9.2% recorded by Njouom [14] in the western region, but lower than the general prevalence in Cameroon (13%). Nevertheless, Menoua Division is still a region of concern. The high prevalence of HBV in the general population of Cameroon may be justified by the fact that screening, the second most affected after Egypt [9]. Results from the present study demonstrated that the prevalence of HCV in the Menoua Division is 6.7%. Although this prevalence is less than the general' observed in Cameroon (11.6%), it is higher than the 4.8% obtained by Noubiap et al. [17] in blood donors population in Edea, Cameroon.
The HCV prevalence results corroborates with the 7.7% reported by Mbanya [18] among pregnant women in Yaoundé, Cameroon. It is worth noting that in Cameroon, HCV prevalence varies from simple to more than double from one region to another. Regional prevalence is therefore of a paramount importance in order to design management strategies against the disease. Hepatitis B is more prevalent (13.8%) than hepatitis C (11.6%) in the general population of Cameroon [14] notwithstanding the prominent campaign of hepatitis B vaccine.
Those findings are in line with results obtained in the present study and further indicate that there is still more to do in order to control the transmission of the disease. Particular attention needs to be paid on medical interventions, sexual activities and disease transmission from mother to child [19]. It was also noteworthy that until the end  it clearly appears that non-viral hepatitis is a serious case of concern in Menoua Division.

Conclusion
The prevalence of viral hepatitis in Menoua Division is high though lower than the national rate. The HBV is more prominent than HCV but there is no difference as far as sex is concerned. Santchou Subdivision was the most affected and people of 20-29 years are the most affected. The prevalence of non-viral hepatitis is also high in this region.

Limits and recommendations: hepatitis management policy
should consider both viral and non-viral types, especially in the Menoua division; update epidemiological data of infectious and noninfectious hepatitis at regional and national levels to assist decisionmaking; identify the risk-factors of non-viral hepatitis; sensitise the local population about the transmission of hepatitis and most importantly, on the precaution to avoid non-viral hepatitis.

What is known about this topic
 Cameroon is one of the countries with higher hepatitis prevalence;  The general prevalence of HBV in Cameroon is about 13%;  Africa has the highest prevalence of HCV, estimated to 5.3%.  The paper helps to understand that the causes of hepatitis in Menoua Division are not only viral. Indeed, the prevalence of non-viral hepatitis is higher than that of viral hepatitis.

Competing interests
The authors declare no competing interests.

Acknowledgments
We acknowledge the collaboration of the different authorities of Health District of Menoua Division and the directors of the different health centres where the work took place.