According to the CDC there are approximately 30,500 acute infections of hepatitis C annually in the United States. In the past the majority of new infections were from blood products (transfusions and organ transplants) and injection drug use. Today the most common reason for acute infections are sharing HCV-infected needles and drug preparation tools (needles, cookers, cottons, water, ties). There have also been outbreaks of acute hepatitis C among HIV-positive men who have sex with men who have unprotected anal sex. There are also new infections from needlestick accidents and from occupational exposure from HCV-infected blood.

There Is No Vaccine To Protect Against Hepatitis C

Acute hepatitis C is rarely fatal unless there is another liver disease present at the time of initial infection or if someone has a severely compromised immune system.

People exposed to the hepatitis C virus usually develop detectable HCV antibodies within one to two months after exposure. In the first two weeks of the acute phase HCV RNA (viral load) quickly rises (5 to 10 million IU/ml [international units]), just before the ALT levels start to peak and symptoms start to appear. The ALT levels will begin to rise as high as 1000 IU/mL, indicating liver inflammation. If any symptoms do appear they can last from 3 to 12 weeks after exposure.

Only about one-third of people initially infected with hepatitis C develop symptoms. These may include flu-like symptoms, jaundice, fever, and nausea.

There is a 20% to 50% chance of spontaneous or natural clearance of the hepatitis C viral infection. The people who develop symptoms are more likely to spontaneously clear the virus (naturally rid the hepatitis C virus from their bodies). The reasons that some people spontaneously clear HCV is not completely understood, but some studies have shown that a broad-based immune response by CD4 and CD8 T-cells to the hepatitis C virus helps to eliminate the virus.

Acute Criteria

The Center for Disease Control and Prevention has a set criteria for the definition of a clinical acute infection: CLINICAL CRITERIA -- An illness with discrete onset of any sign or symptom consistent with acute viral hepatitis (e.g., fever, headache, malaise, anorexia, nausea, vomiting, diarrhea, and abdominal pain), AND (a) jaundice, OR (b) a peak elevated serum alanine aminotransferase (ALT) level >200 IU/L during the period of acute illness. To read more about the Centers for Disease Control and Prevention's criteria for acute HCV infection definitions visit:


If a person tests positive for the hepatitis C virus 6-12 months following exposure, it is called chronic hepatitis C.

The groups that were less likely to spontaneously clear acute hepatitis C include male sex, absence of hepatitis B infection, lack of hepatitis C symptoms, black race, non-genotype 1, older age, people infected with HIV and people who use alcohol and drugs.


There are two recommendations for treating acute hepatitis C:

  • Option 1: Wait 6-12 months to see if the acute infection resolves on its own. If not, treat as chronic HCV infection.
  • Option 2: Treat as chronic HCV infection.


Alan Franciscus is editor-in-cheif at HCV Advocate.