What Is hepatitis C, and how do I know what genotype I have?
Hepatitis C is a virus that is transmitted through blood. People typically become infected with hepatitis C through the use of unclean needles via IV drug use or through receiving a tattoo at an unlicensed location, or through being exposed to infected blood through injury, blood spill, or through receiving infected blood or organs via transplant prior to 1992. Although there is one virus called hepatitis C, the virus has six mutations, called genotypes.
When a person is tested for hepatitis C, they are tested three times. The first test (called the ELISA test) simply tests to see whether the person was exposed to the virus. The second test checks to see whether the blood is infected with hepatitis C. This is because not everyone who is exposed becomes infected and up to 25% of people who are infected actually fight off and cure their infection naturally. The other 75% of people need medical intervention to rid their body from the infection. For those people, a final diagnostic test is performed via blood-work, which tells the doctor which specific type or genotype is within the patient’s body. There are six currently known genotypes and more than 100 sub-types.
What medication is best?
There is no one “best” type of medication for hepatitis C. Different medications are intended to fight different genotypes of the virus. This means that the “best” type of medication for hepatitis C is actually the type that corresponds with your genotype and the “wrong” type of medication is any kind meant for another genotype. In addition, side effects of hepatitis C such as jaundice or liver damage as well as personal medical histories are also taken into account when the doctor prescribes medication to a patient.
The goal of hepatitis C medication is to stop the individual strain or genotype’s replication process, which varies based on the specific RNA strand involved and how it replicates. With the right medication, this is possible. With the wrong drug, the drug offers little to no impact on the replication process and is essentially ineffective. However, no one genotype is more or less likely to lead to liver damage or to the permanent liver damage called cirrhosis. This is why you may know someone else with a hepatitis C medication who may be on a different medical protocol than you are prescribed.
Which medications are specifically prescribed for which hepatitis C genotypes?
Although there are more than 100 sub-types, there are 6 known genotypes of hepatitis C (researchers continue to search for and study more potential genotypes). Each has medication specifically to treat it.
Genotypes 1, 2, and 3 exist throughout the world and have been found in numerous countries. Genotype 4 has been found exclusively in the Middle East, Egypt, and central Africa. Genotype 5 has been found almost only in South Africa, and Genotype 6 is almost exclusively found in Southeast Asia. However, as international travel is common in many countries of the world, people with different genotypes may be found in other countries either because someone is infected in one place and travel or move to another or because people become infected during personal or professional trips.
In the United States, genotype 1 is the most common hepatitis C genotype. It accounts for approximately ¾ or 75% of all infections in the USA. Most of the other genotypes found in the United States are either genotypes 2 or 3.
For people with genotype 1, the direct-acting antiviral drugs boceprevir and telaprevir are most effective. They can also be somewhat effective for people with genotype 2. With the drug sofosbuvir, hepatitis C’s genotype 1 has a cure rate of more than 90% when the person is treated for as few as 12 weeks.
Genotype 2 accounts for 13-15% of all hepatitis C infections within the United States. For these patients, cure rates have been found to be higher than 90% with a daclatasvir plus sofosbuvir combination.
Genotype 3 is had by an estimated 10% of all hepatitis C infections within the USA. The majority of these patients are prescribed peginterferon plus a fixed-dose ribavirin. This provides a cure rate of 65-80%.
Genotype 4 is had by as many as 90% of infections in the Middle East and Africa. The most recently approved drug for this genotype is called Technivie, which is a combination drug that includes ombitasvir, paritaprevir and ritonavir, and is used simultaneously with ribavirin. This provides an approximated 91% cure rate.
Genotype 5 is considered to be the least studied of the genotypes, though new research is being completed and published, so this may change in the near future. The most common treatment for those with genotype 5 is called pegylated interferon which is combined with the drug ribavirin over the course of 6-12 months. Studies show that this medication protocol attained cure rates of 64-71%.
Genotypes 4, 5, and 6 are also being prescribed a new drug called Harvoni. This drug is a combination of ledipasvir and sofosbuvir. After being used for 3-6 months, it has a cure rate of approximately 94%.
Please note that new drugs and new research is being provided to doctors and to the public on a regular basis. This list is not exhaustive, nor is it to be considered a diagnosis for your personal genotype. If you are interested in more information about the medications listed here, please speak with your personal medical practitioner. They will be able to discuss the medications, as well as to explain whether any of these drugs are right for you based on your personal medical history.1-9
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