Hepatitis D
Version: November 2025
Introduction
Hepatitis D, also known as Delta hepatitis, is a liver infection caused by the Hepatitis D virus (HDV), a unique, defective virus that requires hepatitis B virus (HBV) to replicate. It is transmitted through contact with infected blood or bodily fluids, often via needle sharing or sexual contact. Hepatitis D can co-infect with HBV or superinfect individuals already with HBV, leading to more severe liver disease such as cirrhosis or liver cancer. Prevalence is highest in regions where HBV is endemic. Prevention focuses on HBV vaccination and reducing exposure to infected fluids. No specific antiviral treatments currently exist for HDV.
Highlights
- Hepatitis D cases in China show a decline from monthly averages of 40-50 cases during 2016-2017 to around 20 cases by 2025, indicating successful interventions.
- Although 2021 saw a slight increase compared to previous years, the trend generally continued downward, reflecting consistent disease management.
- From early 2024 to November 2025, monthly cases fluctuated between 7 to 30, with some volatility but maintaining overall reduction compared to earlier years.
- Crucially, there have been zero deaths across all years reported, which underscores effective clinical treatment and management strategies for Hepatitis D in the region.
Analysis
Cases Analysis
The data on Hepatitis D cases in the Chinese mainland from January 2016 to November 2025 shows a fluctuating pattern with an overall declining trend over time. In 2016, monthly case numbers ranged from 33 to 60, with peaks in January, November, and August. This pattern continued in 2017 and 2018, though with slightly lower peaks. From 2019, there is a noticeable decline in cases, dropping markedly in 2020, where monthly cases mostly stayed below 22. This declining trend persists across 2021, 2022, and into 2023, with some months in 2024, like September and October, showing very low case numbers compared to previous years.
Throughout the entire period, no deaths are reported, implying effective disease management or characteristics that limit fatalities. While sporadic increases appear in 2025, the overall pattern remains one of decline. This may reflect changes in public health interventions, population behaviors, healthcare access, or seasonal factors affecting transmission. These insights emphasize the importance of ongoing surveillance and targeted public health strategies to sustain the downward trend and prevent resurgence. Understanding these patterns can help inform future measures to improve Hepatitis D management in the region, ensuring efforts are continued to minimize cases and eliminate deaths associated with this disease.
Deaths Analysis
The dataset presented for Hepatitis D cases in mainland China from January 2016 to November 2025 reveals a consistent observation—no deaths were recorded during the entire period. Despite fluctuations in the number of reported cases each month, the mortality associated with Hepatitis D appears to be nonexistent according to this dataset. This suggests either effective management of cases preventing severe outcomes or potentially reflects limitations in data collection or reporting. Given the absence of any reported deaths, we can infer that, during the years covered, the disease was managed well, or the standard of medical care provided for Hepatitis D in China was effectively preventing fatalities.
Examining the overall trend, there is variability in the monthly reported cases, with some months showing higher incidences, such as November 2016 and December 2025, with 53 and 30 cases respectively. While the fluctuations may be attributed to seasonal variations or changing healthcare practices, the absence of deaths may indicate that new cases are primarily managed on an outpatient basis or involve individuals with milder disease presentations. This pattern suggests a relatively lower impact of Hepatitis D in terms of mortality, allowing healthcare providers and policy-makers to focus efforts on disease prevention, patient education, and effective Hepatitis D management strategies to sustain this nonfatal trend. Nonetheless, continued vigilance is necessary to ensure that high-quality clinical practices are maintained to avert potential deterioration in outcomes.