Prevalence and Types of Hepatitis C
HCV is becoming increasingly common, with almost 2 – 3 % of the world’s population harboring the HCV infection. The incidence of new HCV infection ranges from 3 – 4 million each year. HCV is 4x more prevalent than HIV. Around 50-80% of all cases are due to needle sharing and IV drug use. The rate of HCV infection is higher among the prisoners compared to the general population. It is estimated that more than 30000 new cases of acute HCV infection were reported in the United States during 2014 and more than 3.5 million people have a chronic hepatitis C virus infection.
Hepatitis C incidence is more common in African and Asian countries. Egypt has the highest HCV rate (22 %) followed by Pakistan (4.8 %) and China (3.2 %). The HCV infection is the most common risk factor for liver cirrhosis and liver cancer which causes more than 300,000 deaths each year. There is variation in the prevalence of HCV infection in the different geographical area based on the genotypes. In the United States, genotype 1 of HCV causes about 70% of cases while 20% of cases occur by genotype 2. Similarly, in Europe also, genotype 1 infection is very common.
HIV (Human immunodeficiency virus) infection and HCV share common risk factors. Because of this, there are very high chances of co-infection by these two deadly viruses. The co-infection is commonly seen in the injectable drug abusers and the co-infection rate with HIV and HCV varies from 50 – 90 %.
The observational studies that were conducted to determine the risk of cirrhosis in the patients with chronic HCV infection after 20 years demonstrated that 15 % of males and 5 % of females would develop cirrhosis. It is well established that cirrhosis is the preliminary stage of liver cancer at the rate of 4 % per year.
Fortunately, there has been a recent decline in HCV thanks to advances in modern medicine. After integration of screening for blood products before transfusion, HCV transmission rates have dropped.
Types of Hepatitis C
Hepatitis C or HCV is a viral infection of the liver that is transmitted by blood and body fluids. HCV is a small RNA virus with seven different genotypes. Since transmission can occur through sexual contact, some consider HCV a sexually transmitted disease (STD). From the time of contact with the virus to the time of infection is about 6-7 weeks.
Once inside the host, the Hepatitis C virus can remain viable for an indefinite period of time. Outside the body, the virus can be viable and infective for over 3 hours. The virus can multiply in the liver and in the blood cells like lymphocytes.
The HCV infection ranges from mild and short lasting to a life-long serious liver disease. Hepatitis C is classified either as “acute” or “chronic.”
Acute Hepatitis C Infection:
In the acute form of Hepatitis C, the virus causes a temporary illness that occurs within the first 6 months of exposure to the virus. Almost 85 % of the acute HCV patients will go on to develop the chronic infection.
Chronic Hepatitis C Infection:
In chronic, the virus infection causes a long-term illness that can last through the person’s life. When the Hepatitis C virus remains in a person’s body for more than 6 months, it is called as chronic HCV infection. The chronic infection may lead to serious liver problems like cirrhosis (scarring of the liver) or liver cancer.
HCV infection leads to inflammation and death of liver cells. The patient’s immune system plays a crucial role in the control and the elimination of the virus from the body. The immune response is generally triggered in the acute phase of an infection. After the acute infection by HCV, more than 85 % of the patients progress into the chronic state. In chronic hepatitis C, the virus has cleared and the active infection is not present. Unlike the acute phase, chronic HCV infections are usually asymptomatic in initial years. There are mostly identified at the time of routine health check-ups.