If a person has become infected with the hepatitis C virus, it takes a while for their body to produce enough antibodies to be detected. This time is known as the window period.
In this article, we look at how the window period can affect the diagnosis of HCV, and when people should consider getting tested.
When a person is exposed to HCV, it takes time for the body to recognize it as a virus and begin developing antibodies to fight the infection.
Antibodies are chemicals released by the body in response to an infection. The body begins to release antibodies after the virus particles called HCV RNA are detectable.
If testing is done too soon, during the window period, an early negative result may occur. As a result, testing may need to be repeated in some people.
Those with an HCV infection will be contagious even if they have yet to develop symptoms. If someone believes that they might have contracted the virus, they should speak to a doctor to determine the need and timing for testing.
The HCV virus is transmitted through contact with the blood of an infected person. It can be spread through:
- sharing of contaminated drug-injecting equipment, such as needles and syringes
- sexual contact if there is a risk of contact with blood from an infected individual
- pregnancy through transmitted from mother to child
- use and re-use of medical equipment that has not been sterilized
- needlestick injuries, involving the blood of an infected person
- receiving contaminated blood from unscreened sources
- sharing of personal hygiene items, such as razors and toothbrushes, if they involve an infected person's blood
- having a tattoo or piercing in an unregulated practice where hygiene is poor
It is important to point out that the HCV virus cannot be spread through breast milk, food, water, hugging, kissing, or sharing food or drinks with a person who has the virus.
Who should be tested for hepatitis C?
Some people are at a higher risk for getting hepatitis C and should be tested for the disease. These people include:
- those who were born between 1945 and 1965
- current or former injection drug users, or those who use intranasal drugs
- those who were treated prior to 1987 for a blood-clotting disorder
- those who received a blood transfusion or organ transplant before July 1992
- those who are receiving long-term hemodialysis
- those with abnormal liver function tests or liver disease
- those in healthcare or public safety professions who have been exposed to HCV from a needlestick or other injury
- those with HIV, especially HIV-positive men who have unprotected sex with men
- infants who were born to mothers with HCV
If a person suspects or is told that they have been exposed to someone with HCV, they should speak to their doctor about testing.
People who have been in prison or have tattoos and piercings may require HCV testing, depending on the circumstances.
While there are rapid antibody tests available to some people, doctors will typically test a person with a blood test called a hepatitis C antibody test.
The hepatitis C antibody test is used to see if a person has made any antibodies to HCV. If they have, it shows that they have been infected at some point in their lives.
If a person has what is called a non-reactive or negative test result, the person will not appear to have HCV. However, if the test is given during the window period, the result could be inaccurate.
When a person has been exposed to HCV within the previous 6 weeks, re-testing might be recommended.
A reactive or positive result tell a doctor that someone has been infected with the HCV at some point in their lives. The result indicates that their body has created antibodies to fight the virus.
It is important to know that this only means that someone has been infected at some point in time and not that a person still has active HCV. If the infection is present the person may have been cured or got rid of the virus, but they will always have the antibodies.
More tests, such as a nucleic acid test for HCV ribonucleic acid (RNA), will show if an HCV infection is still present. This test measures the amount of the virus in the blood.
Further testing, such as blood tests and a liver biopsy, may be needed to determine the health of a person's liver.
There are six strains of HCV, and each one responds to treatment differently. Testing may be recommended to work out which strain a person has and to help doctors determine the best treatment options.
Although many people affected with HCV do not show symptoms, some may experience the following after an initial infection:
- loss of appetite
- nausea, vomiting, or abdominal pain
- urine that is darker than normal
- clay or gray-colored stool
- joint pain
- yellowing of the skin or whites of the eyes
Many people who have been infected with HCV and have a long-term infection may not show symptoms until liver damage occurs.
The time between exposure to the virus and the first appearance of symptoms is known as the incubation period. For hepatitis C, incubation ranges from 2 weeks to 6 months. On average, however, symptoms occur after around 6 to 7 weeks.
Prevention of HCV includes avoiding doing things that may place a person at higher risk of being infected. To reduce the risk of HCV infection, people should:
- avoid the use of injectable drugs
- avoid sharing needles, syringes, water, or other tools if injecting drugs
- avoid sharing personal hygiene items, such as razors and toothbrushes
- follow universal blood and bodily fluid precautions in healthcare settings
- practice safe sex with the use of latex condoms
- ensure body piercing, tattooing, or acupuncture is done by licensed operators in a clean environment
Some people who are infected with HCV spontaneously clear the infection from their system without treatment.
Acute HCV infections typically occur within the first 6 months after exposure and lead to a chronic form of the disease. Of those who are exposed to the virus, 15 to 45 percent will clear the virus without treatment within 6 months.
For others, treatment is needed. Chronic HCV infections remain in a person's body for a long time. Many infections are lifelong and can lead to significant liver damage, including liver cancer.
Around 60 to 80 percent of those affected by HCV will develop a chronic HCV infection that increases their risk of liver damage.
Currently, there are no hepatitis C vaccinations. However, there are new medications approved by the United States Food and Drug Administration (FDA) that can offer advanced treatment options.