The diagnostic tests for hepatitis C measure different parameters in the blood to establish whether a person has been infected with the hepatitis C virus or not. Naturally, there can be discrepancies in the test results.
The antibody blood test for hepatitis C relies on completing the window period before it can return an accurate result. The window period for hepatitis C lasts for about 4-10 weeks and averages from around two weeks to 5 months. Theoretically, you can have hepatitis for up to 5 months without testing positive, possibly more depending on your immune reaction and the type of test used to diagnose your disease.
While it may take a long time to obtain a definitive diagnosis of hepatitis C using blood tests, it does not mean that the patient and the doctor remain oblivious to the obvious diagnosis at hand. Specific signs and symptoms and findings on the physical exam may constitute enough evidence to formulate a clinical diagnosis of hepatitis C.
HOW LONG CAN YOU HAVE HEPATITIS C BEFORE TESTING POSITIVE?
Testing for hepatitis C is simple but time-consuming. This is because the tests used to diagnose hepatitis C do not return an accurate result immediately after the onset of signs and symptoms. The most common test used to diagnose hepatitis C, the anti-HCV antibody test, takes about 4-10 weeks to return an accurate result, even longer in some patients.
The antibody test result takes such a long time to return an accurate result because it relies on the development of antibodies in a patient. The window period for hepatitis C lasts for about 4-10 weeks, averaging from around two weeks to 5 months. A window period for any disease is when it takes from the initial point of exposure to seroconversion, i.e., antibodies develop in the blood.
The antibody test for hepatitis C cannot accurately result during the window period since the antibodies haven't fully formed yet. The minimum yield for antibodies to be detected by the blood test is achieved only after the window period is over.
So, in theory, a person can have hepatitis C without testing positive for about 5 to 6 months. However, this does not mean that both the doctor and the patient are oblivious to the diagnosis of hepatitis C during this time. Living with hepatitis C without testing positive is different from living with hepatitis C without knowing it.
When a patient presents with initial signs and symptoms, the doctor considers a clinical diagnosis of hepatitis C. This diagnosis is only further supplemented by the positive findings on a physical examination. While the lab tests, or other investigations, have the maximum authority in confirming the diagnosis of hepatitis C, they are not the only means of diagnosis.

CAN YOU GET TESTED FOR HEPATITIS C SOONER?
The anti-HCV antibody test for hepatitis C takes some time before it can return accurate results. However, sometimes a faster confirmatory diagnosis is needed. In such cases, a different test can provide an accurate assessment of a person's HCV status without much delay. This test is known as the HCV RNA test.
The HCV RNA test detects and measures the viral RNA directly in the blood. The viral RNA is a direct measure of the hepatitis virus's presence in the blood. The quantification of the viral RNA allows for the detection of the virus and allows for the measurement of the severity of the disease.
The HCV RNA test can return an accurate result faster than the antibody test. Typically, the viral RNA test has been observed to return accurate results just 1-2 weeks after the initial exposure.
The measure of viral RNA also provides information about what is known as the viral load. The viral load describes how severe the condition is for a patient. Higher viral loads indicate a significant infection with a bad prognosis. Lower viral loads indicate an insignificant infection or an infection that has now improved with or without medication.
WHAT IS CHRONIC HEPATITIS C?
Chronic hepatitis C occurs when the initial acute episode of hepatitis lasts for more than six months, either without the suppression of symptoms or without the clearance of the virus from the blood. According to WebMD, 75% to 85% of all hepatitis C infections turn chronic.
Chronic hepatitis C can be problematic even when it is controlled. This is because the longer the inflammation of the liver stands, the more damage the liver takes. Long-lasting liver damage can result in fibrosis. While the human liver has regenerative abilities, it cannot recover and heal itself from extreme physical assaults, such as fibrosis.
As heinous as it sounds, chronic hepatitis C, however, can be effectively managed and even cured using Direct Acting Antivirals, or DAAs. However, the use of DAAs is only warranted if the extent of the liver damage is still within manageable limits.

WHAT HAPPENS IF I DON’T GET TREATED FOR HEPATITIS C?
Untreated hepatitis C can take one of the three different routes. The acute episode can either 1) heal spontaneously, 2) turn chronic, or 3) cause imminent liver failure. Fortunately, many cases decide to heal spontaneously rather than taking any of the other two dreadful courses of action.
While uncommon, sometimes an untreated acute episode of viral hepatitis C can turn deadly and lead to fulminant hepatic failure. This is common when a person gets infected with more than one genotype of the hepatitis virus simultaneously.
Untreated hepatitis C can turn into chronic inflammation, lasting up to months and even years. Chronic hepatitis C can lead to extensive fibrosis of the liver, known as cirrhosis. Liver cirrhosis is an extremely problematic situation where the normal healthy tissue of the liver is replaced by non-functioning, fibrotic tissue.
Liver cirrhosis can lead to chronic hepatic failure, hepatic encephalopathy, and even the development of liver cancer (hepatocellular carcinoma).