Content Information
Disease Information
Overview
Also known as: Non-A Non-B Hepatitis, HCV Infection
Responsibilities
- Hospital: Report by IDSS, facsimile, mail or phone
- Lab: Report by IDSS, facsimile, mail or phone
- Physician: Report by IDSS, facsimile, mail or phone
- Local Public Health Agency (LPHA): Follow-up dependent on local agency protocol
Iowa HHS
Disease Reporting Hotline: (800) 362-2736
Secure Fax: (515) 281-5698
A. Etiologic Agent
Hepatitis C is caused by an RNA virus (in the Flaviviridae family). Multiple hepatitis C virus (HCV) genotypes exist, with type 1 being most common in the United States.
B. Clinical Description
Hepatitis C is a disease with varying rates of progression. In general, its course is slowly progressive. For people who are recently infected, only 20% - 30% will experience any related acute symptoms. Therefore, it is uncommon for people to be diagnosed with HCV infection in the acute stage. Approximately 15 to 25% of HCV-infected individuals completely recover spontaneously (reasons for this are still unknown). However, the remaining 75 to 85% of people will develop chronic infection.
Most people are asymptomatic during the first decade or two of chronic hepatitis C. Some patients will experience a range of symptoms including fatigue, headaches, joint aches, muscle aches, nausea, jaundice, loss of appetite, and/or abdominal pain. Of those chronically infected, up to 20% eventually develop cirrhosis or cancer of the liver [hepatocellular cancer (HCC)]. Cirrhosis can lead to liver failure in some people and predispose them to the development of liver cancer. Factors related to more serious clinical outcomes include drinking alcohol, coinfection with hepatitis A, hepatitis B, or HIV, and taking medications or food supplements that harm the liver.
Treatment of chronic hepatitis C with Direct-Acting Antiviral (DAA) medications is indicated for individuals and may result in a sustained virologic response with elimination of virus in up to 92% to 99% of those receiving a full 8 to 16 week treatment regimen.
C. Reservoirs
Infected humans are the only known source of this disease.
D. Modes of Transmission
Hepatitis C is a bloodborne pathogen; it is predominantly spread via percutaneous exposure to infectious blood. Currently, the most prevalent mode of transmission is sharing contaminated needles, syringes and other injection drug equipment. Blood transfusions pose an extremely limited risk today, but for those patients who received a blood transfusion prior to July 1992, the risk was approximately 1 in 200 transfused units. Sexual and vertical (mother to infant) transmission of hepatitis C does occur, but does not appear to be an efficient mode of transmission. Other potential risks for transmission include long-term hemodialysis, occupational blood exposure, and tattooing or body piercing with non-sterilized equipment. Hepatitis C is rarely transmitted via sexual contact. Hepatitis C is not spread via casual contact, kissing, sneezing, hugging, breast milk, or sharing glasses or utensils.
E. Incubation Period
The incubation period for hepatitis C ranges from 2 weeks to 6 months, with an average incubation period of 6 - 9 weeks.
F. Infectious Period
Infectiousness with HCV is variable; anyone with a positive test for HCV antibody should be considered infectious until more extensive testing (confirmatory testing using an HCV RNA PCR test) can be done to rule out the presence of the virus in the blood. The virus can usually be detected in an infected person’s blood within 1 to 3 weeks after the initial exposure using a confirmatory test. The degree of correlation between quantity of circulating virus and infectiousness is not clearly established.
G. Epidemiology
In Iowa, there were 23,588 people reported with HCV by the end of 2016. About two-thirds of these people have evidence of chronic infection. HCV infection can occur among persons of all ages. Iowa has seen an increase in diagnoses since 2000, especially among baby boomers (those born between 1945 and 1965) and people under 40. Increases in diagnoses among people under 40 are associated with injection drug use, while baby boomers have likely lived with HCV infection for decades, which they may have contracted through blood transfusions, long-term hemodialysis, tissue and organ transplants, or injection drug use. Although the baby boomers are at risk for complications, including cirrhosis and liver cancer, there is little ongoing transmission occurring in this population. Iowans under 40 with hepatitis C are not at risk for complications at this time, but can transmit the virus.
HCV infection is highly prevalent among people who inject drugs. Several studies have now shown that HCV transmission among people who inject drugs is associated with both direct and indirect sharing of injection equipment, such as cookers and cotton. The risk of occupational exposure for healthcare workers has been estimated to be 1.8% per incident of hollow-bore needle stick exposure to HCV-infected blood. Perinatal transmission is estimated as being about 6%, although if the mother is co-infected with HIV, the risk may increase to approximately 11%.
Hepatitis C is a reportable disease in Iowa. The majority of newly reported cases are not people with new (acute) disease, but those with chronic infection. There is a large population of undiagnosed people who were infected in the past.
H. Bioterrorism Potential
None.
I. Additional Information
The Council of State and Territorial Epidemiologists (CSTE) surveillance case definitions should not affect the investigation or reporting of a case that fulfills the criteria in this chapter. (CSTE case definitions are used by the state health department and the CDC to maintain uniform standards for national reporting.)
Fact Sheets and Forms
References
American Academy of Pediatrics. 2006 Red Book: Report of the Committee on Infectious Diseases, 26th Edition. Illinois, American Academy of Pediatrics, 2006.
Centers for Disease Control and Prevention. Hepatitis C, available at: www.cdc.gov/hepatitis/hcv/index.htm
Centers for Disease Control and Prevention. Recommendations for Prevention and Control of Hepatitis C Virus (HCV) Infection and HCV-Related Chronic Disease, MMWR. 1998; 47:RR-19.
Heymann, D., ed. Control of Communicable Diseases Manual, 20th Edition. Washington, DC, American Public Health Association, 2015.
Iowa Department of Public Health, Bureau of HIV, STD, and Hepatitis. State of Iowa Hepatitis C Virus End-of-Year 2016 Surveillance Report. Iowa Department of Public Health, 2017.
Lenka Benova, Yousra A. Mohamoud, Clara Calvert, Laith J. Abu-Raddad; Vertical Transmission of Hepatitis C Virus: Systematic Review and Meta-analysis, Clinical Infectious Diseases, Volume 59, Issue 6, 15 September 2014, Pages 765–773, https://doi.org/10.1093/cid/ciu447
National Institutes of Health. Management of Hepatitis C. NIH Consensus Statement. June 10-12, 2002.
Resources
CDC Hepatitis C website: www.cdc.gov/hepatitis/HCV/index.htm