Hepatitis B virus infection and its treatment in Eastern Ethiopia

Abstract

Hepatitis B virus (HBV) infection causes acute and chronic hepatitis, compensated and decompensated cirrhosis, and hepatocellular carcinoma worldwide. The actual status of HBV infection and its treatment in certain regions of Asian and African countries, including Ethiopia, has not been well-documented thus far. Antiviral therapy for HBV infection can prevent the progression of HBV-related liver diseases and decrease the HBV-related symptoms, such as abdominal symptoms, fatigue, systemic symptoms and others. In Eastern Ethiopia, HBV-infected patients with cirrhosis were found to be positive for the HBV e antigen and to have a higher viral load than those without cirrhosis. Notably, 54.4% of patients practiced khat chewing and 18.1% consumed excessive amounts of alcohol. Tenofovir disoproxil fumarate effectively suppressed HBV DNA in those infected with HBV. It is important to elucidate the actual status of HBV infection in Eastern Ethiopia to eliminate HBV infection worldwide by 2030. HBV vaccination and the educational programs for Health Science students that provide practical strategies could help to reduce HBV infection in Eastern Ethiopia.

Key Words: Antivirals; Ethiopia; Hepatitis B virus; Liver cirrhosis; Vaccines

Core Tip: To eliminate hepatitis B virus (HBV) infection worldwide by 2030, it is important to determine the actual status of HBV infection in Ethiopia, whose population was estimated 12300000 persons in 2022. At least 10.5% of blood samples from patients in Ethiopia were positive for the HBV surface antigen. In Eastern Ethiopia, HBV surface antigen-positive patients with cirrhosis appeared to be HBV e antigen-positive and had a higher viral load. Tenofovir disoproxil fumarate is effective for the suppression of HBV DNA in these patients. HBV vaccination and the educational programs for Health Science students that provide practical strategies could also reduce HBV infection in Eastern Ethiopia.

TO THE EDITOR

Although hepatitis B virus (HBV) infection is a major cause of acute and chronic hepatitis, cirrhosis and hepatocellular carcinoma worldwide[1,2], the actual condition of HBV infection and its treatment in certain regions of Asian and African countries has not been well documented[3,4]. As the prevalence of HBV infection varies geographically, with East Asia and sub-Saharan Africa having the highest rates[1,4], elucidation of the prevalence of HBV infection in Asian and African countries is critical to determine the exact prevalence of HBV infection and its treatment status in these regions.

Universal HBV vaccination and screening are useful for preventing mother-to-child vertical transmission or the horizontal transmission of HBV among adults[5,6]. However, a recent systemic review and meta-analysis demonstrated that the effectiveness of the hepatitis B vaccine among vaccinated children in Ethiopia was significantly heterogeneous, not meaning the consistent effectiveness of HBV vaccination[7].

Antiviral therapies for HBV infection in Ethiopia

Although eliminating HBV covalently closed circular DNA is difficult, controlling HBV infection is easier than before, owing to the development of nucleos(t)ide analogues (NUCs) and peginterferon have been developed[8-12]. Prolonged antiviral treatment reduces the incidence of hepatocellular carcinoma[13,14], hepatic decompensation[15], or varices[16] in patients with HBV infection and compensated cirrhosis or hepatic fibrosis in patients with HBV infection[17]. Long-term HBV DNA suppression with potent NUCs may be ineffective for patients who are co-infected with the hepatitis delta virus[18,19].

Teshome et al[20] reported that antiviral therapy for HBV infection improved mental and physical health-related quality of life and chronic liver disease questionnaire scores[21] which are associated with a poorer quality of life, at the University of Gondor Comprehensive Specialization Hospital, Gondor, Northwest Ethiopia. Thus, antiviral treatment also reportedly improves the health-related quality of life especially in patients with compensated HBV cirrhosis[22].

HBV infection in Ethiopia

The population of Ethiopia was estimated to be 12300000 persons in 2022[23]. At least 815 of the 7789 (10.5%) of blood samples collected from patients in Ethiopia were positive for HBV surface antigen (HBsAg) (indicating HBV infection). Among the 815 HBV-positive samples, 630 were subjected to HBV genotyping, which revealed a prevalent trend of mixed HBV genotype infections: HBV genotypes A/E/F (67.30%). The prevalence rates of hepatitis C virus (HCV) and human immunodeficiency virus (HIV) coinfections were 13.0% for HBV/HIV, 3.3% for HBV/HCV and 2.1% for HBV/HIV/HCV coinfections[24]. The prevalence of HBV among pregnant women in East Africa is estimated to be 6.0%[25]. Therefore, elucidating the actual status of HBV infection in this area is critical to eliminate HBV infection worldwide by 2030.

HBV infection in East Ethiopia

Ismael et al[4] reported chronic HBV infection in Eastern Ethiopia and demonstrated that the clinical characteristics and determinants of cirrhosis. They studied 193 HBV-infected patients without HIV or HCV infection with the following characteristics. Median age: 30 years (inter quartile range: 24-38); male: 132 (68.4%); Oromia region origin: 71 (36.8%); married: 123 (63.7%); and farmers: 33 (17.1%). Among the 193 patients, 105 (54.4%) practiced khat chewing and 35 (18.1%) consumed excessive amounts of alcohol.

A total of 115 (59.6%) of the 193 patients were symptomatic. Jaundice, abdominal pain, abdominal swelling, edema, nausea/vomiting, hematemesis, pruritus, muscle/joint aches, confusion and weight loss were observed as symptoms in 34 (17.6%), 69 (35.8%), 57 (29.5%), 32 (16.6%), 36 (18.7%), 24 (12.4%), 18 (9.3%), 44 (22.8%), 13 (6.7%), and 51 (26.4%), respectively, of the 193 patients. These symptoms, other than pruritus and confusion, were observed more often in patients with cirrhosis than in those without. Underweight (body mass index < 18.5 kg/m²), edema, jaundice, pale conjunctiva, palmar erythema, gynecomastia, ascites and splenomegaly were observed as signs in 34 (17.6%), 30 (15.5%), 12 (6.2%), 10 (5.2%), 14 (7.3%), 8 (4.1%), 29 (15.0%), and 34 (17.6%), respectively, of the 193 patients. These clinical signs were significantly more common in patients with cirrhosis than in those without. Differences in laboratory testing results slightly varied. The median fibrosis-4 score was 1.06 (inter quartile range: 0.60-198), and 30 (17.4%) patients had a fibrosis-4 score ≥ 3.25, indicating advanced fibrosis. Among the 133 patients whose HBV e antigen (HBeAg) status was examined, only 28 (21.1%) were HBeAg-positive. Among the 177 patients whose HBV DNA levels were examined, 114 (64.4%) had a viral load of less than 2000 IU/mL. Patients with cirrhosis were found to be HBeAg-positive and to have a higher viral load than those without cirrhosis.

The 60 cirrhotic patients were often common among males, khat users, farmers, and from the Oromia region. Among the 60 patients diagnosed with cirrhosis, 35 (58.3%) had decompensated cirrhosis. Multivariate analyses revealed that khat overuse [adjusted odds ratio (aOR) = 2.86, P value = 0.003], HBeAg positivity (aOR = 3.81, P value = 0.022), and HBV DNA viral load > 2000 IU/mL (aOR = 5.29, P value = 0.005) were independently associated with cirrhosis.

Notably, 8 (66.7%) of the 12 patients who died had decompensated cirrhosis. Among the study patients, 59 (30.6%) started treatment with tenofovir disoproxil fumarate. Among these patients, 80.9% and 100% of the patients achieved viral suppression 12 months and 24 months after the initiation of treatment, respectively[4]. Among the 29 patients who completed 24 months of treatment, 21 (72.4%), 6 (20.7%) and 2 (6.9%) demonstrated an excellent, medium and poor adherence, respectively. As virological suppression is also dependent on the adherence to medication[26], tailored educational programs may equip Health Science students with practical strategies[27].

This study had several limitations[4], such as the lack of information about the number of patients; follow-up periods; host and viral factors, such as HBV genotypes[28], HBeAg status[29], HBsAg levels[30]; and hepatitis B core-related antigen levels[12], which impact on the prognosis of patients with chronic HBV infection. Although the present standard-of-care treatments for HBV infection are NUCs and peginterferon, an antisense oligonucleotide[8,31], an orally bioavailable small molecule inhibitor of HBV replication[32] and HBV capsid assembly modulators[33,34] are under development. However, further studies are needed.

Conclusion

HBV infection in Eastern Ethiopia is largely poorly understood. Advanced liver diseases, including decompensated cirrhosis, are often observed in HBsAg-positive patients in this region. Treatment with tenofovir disoproxil fumarate could lead to effective viral suppression. The follow-up of patients treated with tenofovir disoproxil fumarate for longer periods will allow of the elucidation of the effects on patients with HBV infection in this area. HBV vaccination and the educational programs for Health Science students that provide practical strategies may reduce the incidence of HBV infection in Eastern Ethiopia.