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FACT SHEET: Hepatitis C (also known as “HC”, “HCV infection”, “parenterally transmitted non-A non-B hepatitis”, and “post-transfusion non-A, non-B hepatitis”; caused by hepatitis C virus — HCV)

Date of Publication: May 19, 2015

Is the initiation of non-invasive dental hygiene procedures* contra-indicated?

  • Yes, if the patient/client has active hepatitis (acute or chronic). [Note: HC has a chronic, life-long carrier state, which does not necessarily preclude dental hygiene procedures, but for which standard precautions should be exercised.] 

Is medical consult advised?  

  • Yes, if patient/client is not receiving ongoing medical care/monitoring for chronic carrier state or significant morbidity (e.g., end-stage liver disease).
  • If patient/client has history or systemic manifestations suggestive of active hepatitis (acute or chronic), prolonged bleeding time, severe liver disease, or previously undiagnosed chronic carrier state, timely referral to physician is indicated for definitive diagnosis and assessment of degree of infectivity and liver dysfunction (e.g., serology and liver enzyme/function blood tests), as well as management (including potential hepatologist — liver specialist —  involvement and consideration of antiviral therapy). Instruct patient/client to reschedule dental hygiene appointment until medical clearance has been obtained.

Is the initiation of invasive dental hygiene procedures contra-indicated?**

  • Yes, if the patient/client has active hepatitis (acute or chronic) or prolonged bleeding time. (Note: HC has a chronic, life-long carrier state, which does not necessarily preclude dental hygiene procedures, but for which standard precautions should be exercised.)

Is medical consult advised? 

  • See above. 

Is medical clearance required? 

  • Yes, if active hepatitis (acute or chronic) or prolonged bleeding time or severe liver disease is suspected on the basis of history and/or examination.1 Also, medical clearance may be required if patient/client is being treated with antiviral medications2 associated with immunosuppression +/- increased risk of infection +/- prolonged haemostasis (e.g., interferon and ribavirin). Patients/clients on antiviral therapy should be assessed by their physician prior to invasive dental procedures to ensure safety. Non-urgent oral treatment may need to be postponed until antiviral therapy has ceased.

Is antibiotic prophylaxis required?  

  • No. However, patients/clients with severe liver disease may be more susceptible to dental infection; selection of antibiotic should be based on risk and severity of infection. 

Is postponing treatment advised?

  • Yes, if the patient/client has active hepatitis (acute or chronic) or is not receiving ongoing medical care/monitoring for severe liver disease or chronic carrier state, or if prolonged bleeding time is suspected. See “medical consult” above.

Oral management implications

  • Mode of transmission: primarily parenterally (i.e., via infected needles in the healthcare or injection drug use or tattooing/body piercing settings; receiving a blood transfusion in Canada prior to 1990); sexual and mother-to-child transmission can also occur, as can HCV transmission via close household contact (e.g., sharing toothbrush, razor, or nail clippers). While the infectivity of HCV is lower than of hepatitis B virus, HCV can survive at room temperature on dry surfaces for up to 6 weeks, resulting in a longer period of potential environmental transmission.
  • All patients/clients who are HCV RNA positive are potentially infectious.3 50% to 85% of persons who contract HCV become chronic carriers; i.e., they are potentially infectious for life if untreated.
  • HCV infection poses considerably lesser transmission risk than does hepatitis B after occupational exposure to blood (about 1/10 the risk of hepatitis B virus transmission), although the transmission risk is about 10 times that of HIV.4
  • After percutaneous (e.g., needle stick) or permucosal exposure to blood from an HCV RNA positive (or anti-HCV positive, in the absence of HCV RNA testing) patient/client, baseline testing of the exposed person should be undertaken (including HCV RNA, anti-HCV, and aminotransferase levels) and repeated again at 3 and 6 months after exposure. This approach enables early intervention and treatment. (At present, neither immune globulin [IG] or preemptive therapy with antiviral agents is recommended.)  
  • If you, the dental hygienist, contract hepatitis C and become a carrier (chronically HCV positive), you should seek medical advice regarding any potential restrictions on professional activity. (Typically, there are no restrictions on professional activity unless there is epidemiological linkage to transmission of disease.) There is no commercially available hepatitis C vaccine, and prophylactic immune globulin (IG) is ineffective. However, current antiviral treatment of chronic hepatitis C is highly effective, resulting in cure of most of those treated.
  • Certain drugs requiring or affecting liver metabolism may need to be avoided or reduced in dosage in patients/clients with liver disease (e.g., acetaminophen, aspirin, ibuprofen, codeine, local anaesthetics, and some antibiotics).
  • Excessive bleeding (due to reductions in coagulation factors and platelets) may occur in patient/clients with chronic active hepatitis or end-stage liver disease; these persons may need vitamin K and/or platelet or clotting factor replacement for certain oral procedures.
  • Portal hypertension5 in patients/clients with end-stage liver disease may result in low systolic blood pressure; therefore blood pressure should be monitored in such persons.
  • Patients/clients with chronic HC may be on antiviral therapy, which can impact oral care (see above and below).
  • Prior to commencing anti-HCV therapy, active oral disease should be managed. Failure to do so may delay the onset of treatment for HC.
  • In Ontario, hepatitis C is a specified Reportable Communicable Disease (as per Ontario Regs 559/91 and amendments under the Health Protection and Promotion Act). Thus, physicians and laboratories are obligated to report these diseases to the local Medical Officer of Health so the local public health unit can ensure affected persons are appropriately managed and further disease transmission is minimized.
  • To reduce oral acquisition and spread of viral hepatitis (and other sexually transmitted illnesses), condoms or dental dams should be used for all oral-genital and oral-anal contact.

Oral manifestations

  • The oral mucosa may have a yellow-brown cast during the icteric (jaundice) phase of acute hepatitis, and dysgeusia (altered, usually unpleasant, taste) may also occur.
  • Abnormal bleeding can result from chronic hepatitis and significant liver damage (or cirrhosis).
  • Chronic viral hepatitis increases risk for hepatocellular carcinoma (liver cancer), which may rarely metastasize to the jaw. Oral metastases manifest as hemorrhagic expanding masses located in the ramus and premolar region of the mandible.
  • Extrahepatic immunologic manifestations of chronic HCV infection include lichen planus (manifesting as lacy white patches in the mouth, sometimes with painful sores) and Sjögren-like syndrome (lymphocytic sialadenitis). HCV infection has also been linked to xerostomia, aching in the mouth, and periodontal disease.
  • Antiviral therapy used to treat hepatitis C may result in oral side effects. For example, interferon (largely supplanted by newer, more effective, and better tolerated antiviral medications) may cause dry mouth; bleeding, tender or enlarged gums; and dysgeusia (bad taste).

Related signs and symptoms

  • Viral hepatitis is inflammation of the liver resulting from certain viral infections. (Hepatitis may also result from chemical agents, such as alcohol and certain drugs.)
  • About 194,500 persons are estimated to be chronically infected with HCV infection in Canada (about 0.5% of the population) but many don’t know it. Worldwide, 130—150 million people are chronically infected with HCV. While North America is considered a low prevalence region, endemicity is higher in several countries in Latin America, Eastern Europe, and the former Soviet Union, as well as in many African, Middle Eastern (particularly Egypt), East and South Asian (except Japan), and Pacific Island countries.
  • Following the incubation period (2 weeks to 6 months, typically 6 to 9 weeks), the clinical course of acute viral hepatitis C manifests variably in the prodromal (pre-icteric/pre-jaundice) phase as malaise, fatigue, weakness, decreased appetite, nausea, vomiting, right upper quadrant (liver) abdominal discomfort, and fever. The icteric phase is heralded by the onset of jaundice (yellow-brown discolouration resulting from bilirubin accumulation) of the conjunctivae and skin (and oral mucosa).  Dark urine may also occur, and stool colour may lighten, often in association with pruritus (itchiness). In severe cases, enlargement of the liver and spleen may occur. During the convalescent or recovery (post-icteric) phase, symptoms disappear, but hepatomegaly (liver enlargement) and abnormal liver function values may persist for a variable period.
  • 60% to 90% of persons who become infected with HCV do not have acute signs/symptoms. About 25% of persons contracting HCV eventually become jaundiced to some degree. Fulminant hepatitis, coagulopathy (involving increased bleeding time), encephalopathy, and cerebral edema are rare manifestations.
  • Nonspecific symptoms of hepatitis C (e.g., weight loss, fatigue, sleep disorder, difficulty concentrating, right upper quadrant abdominal pain, and liver tenderness) may not appear until cirrhosis, hepatic fibrosis, or hepatocellular (liver) cancer are present.  
  • Chronic hepatitis is associated with liver abnormalities, but it is often asymptomatic for 10 to 30 years. Signs of advanced liver disease include bleeding esophageal varices, ascites (fluid in the abdomen), jaundice, spider angiomas6, and dark urine.
  • Extrahepatic immunologic disorders associated with chronic HCV infection include immune complex-mediated diseases (e.g., vasculitis and polyarteritis nodosa) and autoimmune disorders (e.g., rheumatoid arthritis, thyroiditis, glomerulonephritis, thrombocytopenic purpura, and pulmonary fibrosis). Non-Hodgkin lymphoma is another uncommon extrahepatic manifestation.
  • Chronic infection results in 50% to 85% of adults contracting hepatitis C. About half of these persons, if untreated, will develop cirrhosis or liver cancer.
  • Since the early 1990s (and particularly in the 2010s), treatment advances have radically changed the prognostic picture for persons in the developed world with chronic hepatitis C. Today, treatment cures 95% of affected persons in Canada. 
  • Carriers of HCV can appear healthy and symptom-free and still spread infection to others.

References and sources of more detailed information

Date: January 27, 2015
Revised: February 14, 2020; May 19, 2020; October 31, 2023


1 Clearance/consultation with the patient/client’s physician can establish the level of chronic liver disease and its control (e.g., including bloodwork such as complete blood count [CBC] and liver enzymes such as aspartate aminotransferase [AST] and alanine aminotransferase [ALT]) and can identify bleeding tendencies (e.g., including bloodwork such as prothrombin time [PT] and partial thromboplastin time [PTT]).
2 Interferon and ribavirin, which were the main antiviral treatments available for treatment of hepatitis C in Canada in the early 1990s, have either been supplanted entirely or in part by newer, more effective (and, in many cases, better tolerated and shorter duration) medications. These newer hepatitis C drugs — often given in combination format — include velpatasvir, sofosbuvir, glecaprevir, pribentasvir, ledipasvir, daclatasvir, elbasvir, grazoprevir, and voxilaprevir.
3 Because a positive HCV antibody test (anti-HCV) cannot distinguish someone who was previously infected but resolved or cleared the infection from someone with current infection, it is critical that HCV RNA testing follow a positive HCV antibody test to identify persons with current (chronic) HCV infection.
4 Portal hypertension is an increase in the blood pressure of the portal venous system. Veins coming from the stomach, intestine, spleen, and pancreas merge into the portal vein, which then branches as it travels through the liver. If the branching vessels are blocked due to liver damage, blood cannot flow properly through the liver. This results in increased pressure in the portal vein, which may lead to the development of varices (large, swollen veins) within the esophagus, stomach, rectum, or umbilical area. Varices can rupture, resulting in potentially life-threatening complications.
5 Spider angiomas are enlarged arterioles — resembling the body of a spider — from which smaller blood vessels (that resemble spider’s legs) spread near the surface of the skin.

* Includes oral hygiene instruction, fitting a mouth guard, taking an impression, etc.
** Ontario Regulation 501/07 made under the Dental Hygiene Act, 1991. Invasive dental hygiene procedures are scaling teeth and root planing, including curetting surrounding tissue.