Being infected with HCV does not necessarily mean that liver disease will occur. What’s more, it can take several years—decades, in many cases—for HCV to cause life-threatening liver disease.
Soon after HCV enters the body, it infects cells in the liver called hepatocytes. Only a small number of people (about 25 percent) actually experience symptoms of infection, such as fatigue, decreased appetite, nausea or jaundice (yellowing of the skin and eyes). However, almost all people infected with HCV experience an increase in their liver enzymes—such as serum alanine aminotransferase (ALT)—which can be detected by a simple blood test. An increase in ALT means that some liver cells are becoming damaged by the HCV infection.
About 15 to 25 percent of people infected with HCV are able to clear the virus from their bodies, usually within six months after becoming infected (more common among infected infants and young women). However, the majority of people infected with HCV have “chronic” hepatitis C—an infection that will stay with them for life. In other words, if 100 people are infected with HCV tomorrow, 15 to 25 of them will clear the virus from their bodies within six months, whereas 75 to 85 of them will remain infected with the virus.
Of the 75 to 85 people with chronic hepatitis C, about 15 of them will remain healthy—their liver enzymes will stay normal, even though HCV can be detected in their livers and in their blood, and they will not go on to develop liver disease or experience symptoms of the infection. The remaining 60 to 70 people with chronic hepatitis C will go on to experience some signs and symptoms of liver disease, such as fatigue, nausea, muscle aches and abdominal pain.
About 5 to 20 of these people, usually over a 20- to 30-year period of HCV infection, will develop cirrhosis—a scarring of the liver that results from widespread fibrosis (an extreme overgrowth of the liver’s connective tissue). Progression to cirrhosis may be accelerated in people who are older, obese or immune-suppressed (people coinfected with HIV). Heavy alcohol use can also speed up liver disease, notably men who drink more than 50 grams of alcohol a day (5 drinks) and women who consume more than 30 grams of alcohol a day (3 drinks).
Although cirrhosis is not life threatening, it can affect the way the liver works and it does increase the risk of liver cancer. Of the 5 to 20 people with HCV who develop cirrhosis, between 1 and 5 will die from the consequences of chronic HCV infection, notably liver cancer or liver failure.
HIV can worsen hepatitis C. Not only does HIV increase the risk of liver damage, but it can also hasten the onset of liver damage following infection. Hepatitis C coinfection can also complicate HIV treatment, since some antiretrovirals (ARVs)—HIV medications—are less liver-friendly than others. To learn more about HIV/HCV coinfection, see the comprehensive lesson plan published on AIDSmeds.