Hepatitis C epidemiology and demographics
Hepatitis C epidemiology and demographics On the Web
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Hepatitis C is a major health problem that affects approximately 2 to 4 million people in the United States, 5 to 10 million people in Europe, and 12 million people in India. Approximately 150,000 new cases occur annually in the United States and in Western Europe, although accurate incidence rates are difficult to estimate given the asymptomatic nature of the early stages of the disease. While the prevalence of the disease appears to be declining, hepatitis C is still highly prevalent in certain areas of the world. Egypt is the country with the highest prevalence of HCV, HCV-associated cirrhosis, and hepatocellular carcinoma, and the prevalence tends to increase with age, suggesting ongoing development of new cases of HCV. Approximately one-fourth of all cases of cirrhosis and hepatocellular carcinoma are attributed to HCV worldwide. Hepatitis C affects males and females equally.
Epidemiology and Demographics
Incidence and Prevalence
- According to the World Health Organization (WHO), approximately 3% of the global population are infected with chronic hepatitis C virus (HCV). More than 170 million people are infected chronically around the world. The prevalence of HCV varies among different nations; for example, 1.3% to 1.6% of the U.S. population are affected, while up to 30% of Egypt population are infected with hepatitis C virus.
- Figures in individual countries also vary greatly: Approximately 2-4 million persons are infected with chronic HCV in the United States, 5-10 million in Europe, and more than 10 million in India.
- Acute HCV infection follows an asymptomatic course, which makes the accurate determination of HCV incidence difficult. Additionally, many countries lack sufficient epidemiological data. Nonetheless, it is estimated that approximately 150,000 new cases are reported in the United States and Western Europe annually, whereas the incidence in Japan is as high as 350,000 new cases each year. More than 60-80% of patients with HCV infection become chronic carriers of the disease, with an overall number of chronic carriers reaching approximately 170 million patients. The trend today is marked by a progressive decrease in new HCV infections, characterized by a remarkable 80% decrease since the infection was first discovered in 1989-1990.
- In 2014, a total of 2,194 cases of acute hepatitis C were reported to the CDC from 40 states.
- The overall incidence rate for 2014 was 0.7 cases per 100,000 people, an increase from 2010–2012.
Prevalence of HCV rises significantly in specific populations:
- Intravenous drug users: > 70% (Accounts for most modern cases of HCV infection)
- Hemophilia patients: > 70%
- Hemodialysis: 20-30%
- The morbidity associated wth chronic hepatitis C, mainly due to complications is estimated to be 350,000 liver-related deaths per year.
- The age of infected patients varies across regions. In the United States, Australia, and Western Europe, more than 65% of HCV infections are observed in patients between 30-50 years. These numbers suggest that most cases of HCV in these regions occurred before 1990. On the other hand, there is an increase of HCV prevalence with age in countries such as Turkey, Spain, Italy, Japan, China, and Egypt. Most patients in these countries are older than 50 years of age.
- In 2014, among all age groups, people ages 20–29 years had the highest rate (2.20 cases per 100,000 people) and people aged 0–19 and ≥60 years had the lowest rate (0.12 cases per 100,000 people) of acute hepatitis C.
In 2014, rates of HCV among males and females in the United States were 0.8 and 0.7 cases per 100,000 people, respectively.
Morbidity and Mortality
HCV is a global disease. The most highly endemic region of HCV—especially genotype 4a—is Egypt, due to a history of non-hygenic medical and paramedical practices in the country. As many as 25% of Egyptian blood donors are chronic carriers of HCV infection. In contrast, the United Kingdom and Scandinavia have a low prevalence of HCV compared to other regions.
In some countries, HCV is prevalent in specific regions rather than the entire counrty. Such patterns are observed in Italy, China, and Japan.
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