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Running head: SCREENING CAPSTONE PROJECT HCV SCREENING CAPSTONE PROJECT HCV Tracy Liichow MPH 510 01 Spring A 2014 Applied Epidemiology Instructor: Dr. Carol Hoban CONCORDIA UNIVERSITY, NEBRASKA February 28, 2014 SCREENING CAPSTONE PROJECT HCV 2 Abstract Prevention of infectious diseases includes screening or testing. What is first and foremost in our thinking is our objective which is to prevent infection. Hepatitis C is a liver disease that is the consequence of infection with the Hepatitis C virus. The disease can cause serious health problems for many of the people infected and the health problems include liver damage, cirrhosis, and perhaps even death. Hepatitis C is a leading cause of liver cancer and the leading reason for liver transplants and individuals diagnosed with Hepatitis C often do not have any symptoms. Though they may not have any symptoms, their blood is infectious which makes screening essential if we are to curb the rise of HCV infection in the United States. Keywords: screening for disease, HCV, HCV testing, Hepatitis C SCREENING CAPSTONE PROJECT HCV 3 SCREENING CAPSTONE PROJECT HCV This screening project subject is the Hepatitis C Virus or HCV. The specific target population is African Americans born between 1945 and 1965, commonly referred to as baby boomers. According to the Centers for Disease Control (CDC) (2013): Hepatitis C virus (HCV) infection is the most common chronic bloodborne infection in the United States; approximately 3.2 million persons are chronically infected. Although HCV is not efficiently transmitted sexually, persons at risk for infection through injection drug use might seek care in STD treatment facilities, HIV counseling and testing facilities, correctional facilities, drug treatment facilities, and other public health settings where STD and HIV prevention and control services are available. (p. 1) The recommended setting for this type of project would be an HIV counseling and testing facility located in Detroit, Michigan. However, I also recommend different types of settings with inclusion of primary care and home testing kits. Background The background for this analysis includes accessing epidemiological data and studies from the CDC as well as peer reviewed publications. General information on HCV There are approximately 60 notifiable diseases identified by law at the federal level in the United States, and viral hepatitis is one of those diseases (Schneider, 2013). Viral hepatitis is a group of viral infections that affect the liver. This paper focuses on hepatitis C and the virus that causes it. Therefore, HCV can lead to acute and chronic liver disease in people who are infected with it. SCREENING CAPSTONE PROJECT HCV 4 HCV “is a small, enveloped RNA virus belonging to the Flaviviridae family, genus Hepacivirus” (Penin, Dubuisson, Rey, Moradpour, & Pawlotsky, 2004, p. 5). HCV “is a positive-stranded RNA virus” (Rosenberg, 2001, p. 451). An organism’s complete set of DNA or RNA, including all of its genes, is called a genome (US National Library of Medicine, NIH, US HHS, 2013). “The HCV genome is approximately 906 kb in length and the proteome encoded is a polyprotein of a little more than 3000 amino acid residues” (Rosenberg, 2001, p. 451). We have classified HCV into six genotypes and as HCV “evolved in the population, the variations in genome sequences have become more dramatic” (Jensen & Reau, 2013, p. 3). A proteome is all of the proteins produced by an organism; it is an entire set of proteins (American Medical Association, 2013). The HCV proteome polyprotein “is processed by a combination of host and viral proteases into structural and non-structural proteins” (Rosenberg, 2001, p. 451). HCV disperses in several forms in the serum of an infected host and it subsists within its hosts as a collection of genetically distinct yet closely related variants (Penin et al., 2004, p. 7). The HCV envelope proteins behave like “other viral envelope proteins involved in host cell entry” and stimulate the joining together of the viral envelope and “a host cell membrane” (Penin et al., 2004, p. 9). Epidemiologist Kenrad E. Nelson (2007, p. 924) indicated “HCV infections are often persistent, indicating that the virus has evolved mechanisms to escape immune surveillance.” HCV is generally asymptomatic in the early stages. Most people infected with it are not conscious of that fact and could have been infected for years without symptoms. According to Sue Parini (2001, p. 18), a leading Registered Nurse and Infection Control Manager, “An estimated 10,000 deaths each year in the United States are related to hepatitis C, but that number SCREENING CAPSTONE PROJECT HCV 5 is expected to triple in the next few decades as the infection progresses in people who've been asymptomatic.” Transmission According to the CDC (2013b) HCV transmission is transmitted primarily through percutaneous1 or parenteral2 exposure that can result from injection-drug use, needle-stick injuries, and inadequate infection control in health-care settings. Additionally, even though this does not occur as frequently, HCV transmission occurs among HIV-positive persons, especially men who have sex with men (MSM), as a result of sexual contact with an HCV-infected partner, among persons who received non-professionally applied tattoos and among infants born to HCVinfected mothers. Common screening test for HCV The U.S. Preventive Services Task Force (USPSTF) (2013) recommends screening for hepatitis C virus (HCV) infection in persons at high risk for infection and extending one-time screening for HCV infection to adults born between 1945-1965. “Because HCV progresses slowly, the risk for serious complications is increasing among infected Americans as time passes. Without changes in current case identification and treatment, deaths from HCV are forecasted to increase to 35 000 annually by 2030” (Rein et al., 2012, p. 1). More than 75% of individuals infected with HCV are baby boomers, defined as people born from 1945 through 1965. Among baby boomers, rates of Hepatitis C are higher in African Americans. In fact, African American boomers are twice as likely to have Hepatitis C as are other baby boomers (Dean, 2014). “Detection of antibodies to the hepatitis C virus is the first step to screen patients . . . The presence of HCV antibodies is indicative of either past, current, or resolved infection and cannot discriminate between acute and chronic HCV infection ” (Jensen & Reau, 2013, p. 29). What SCREENING CAPSTONE PROJECT HCV 6 about testing and serologies? Two weeks after exposure to the virus HCV RNA is detectable by assays; however, HCV antibodies do not become detectable until approximately 8 to 12 weeks after exposure (Jensen & Reau, 2013). There are a number of different blood tests used to test for Hepatitis C. Physicians have the prerogative in ordering just one or a combination of the available tests. Usually, an individual will first receive a screening test that will show whether he or she has developed antibodies to HCV. “Having a positive antibody test means that a person was exposed to the virus at some time in his or her life. If the antibody test is positive, a doctor will most likely order a second test to confirm whether the virus is still present in the person's bloodstream” (Centers for Disease Control and Prevention, 2014, p. 1). What is the screening test? According to Natasha Walzer, MD (2013, p. 30), “The screening test is an enzyme immunoassay (EIA) that detects antibodies to recombinant antigens from core and nonstructural proteins that make up the HCV virion.” A serological test will be performed. A serological test is any of several laboratory procedures carried out on a sample of blood serum, the clear liquid that separates from the blood when it is allowed to clot. The purpose of such a test is to detect serum antibodies or antibodylike substances that appear specifically in association with certain diseases. An immunoassay is a laboratory or clinical technique that uses the specific binding between an antigen and its homologous antibody to identify and quantify a substance in a sample. The Mayo Clinic (n.d.) describes HCV testing in the following manner: Laboratory testing for HCV infection usually begins by screening for the presence of HCV antibodies (anti-HCV) in serum, using an FDA-approved anti-HCV screening test. Specimens that are repeatedly reactive by screening tests should be confirmed by more HCV-specific tests, such as direct detection SCREENING CAPSTONE PROJECT HCV 7 of HCV RNA by reverse transcriptase-PCR (RT-PCR). . . Current screening serologic tests to detect HCV antibodies include EIA and chemiluminescence immunoassay. Further the Mayo Clinic (n.d.) suggests that despite “the value of serologic tests to screen for HCV infection, several limitations of serologic testing exist: There may be a long delay (up to 6 months) between exposure to the virus and the development of detectable HCV antibodies. False-reactive screening test results can occur. A reactive screening test result does not distinguish between past (resolved) and chronic HCV infection. Serologic tests cannot provide information on clinical response to anti-HCV therapy.” An example of an FDA approved anti-HCV screening test is the over-the-counter testing kit, Hepatitis C Check, Home Access Health Corporation. “The blood sample is obtained at home using a lancet and shipped in a weather-resistant pouch” (Walzer & Cotler, 2013, p. 31). Direct detection of HCV RNA is used as a confirmatory test. List information on specificity, sensitivity, and PV+ and PV- for screening test for HCV Specificity is the probability that the test result will be negative when administered to persons who are actually without the antibody. Sensitivity is the probability that the test result will be positive when administered to persons who actually have the antibody. The sensitivity of the Hepatitis C Check testing kit method “has been shown to be comparable to hospital-based laboratory testing” (Walzer & Cotler, 2013, p. 31). SCREENING CAPSTONE PROJECT HCV 8 Predictive-value positive (PVP) is the probability that a person with a positive screening test result actually has the antibody. Predictive-value negative (PVN) is the probability that a person with a negative screening test result actually does not have the antibody. An example of specificity, sensitivity, and PV+ and PV- for a screening test for HCV is a study which compared a newly developed automated and quantitative HCV core antigen test with the HCV RNA assay. According to Kesli (2011) one of the conductors and authors of the study: Among the 212 specimens tested, all 52 cases in which HCV RNA was not detected were also nonreactive for HCV Ag. For all samples with an HCV RNA-negative result, a new sample was retested twice, 2 and 4 weeks later, and all of them were again found to be negative. HCV Ag was found to be negative in only 6 out of 160 HCV RNA-positive samples; these samples had low-level viremia (5 samples with HCV RNA at levels between 75 and 249 IU/ml and 1 sample with 6,562 IU/ml). All the HCV Ag-reactive cases (n = 154) were also found to be positive with the anti-HCV test. Of all the 38 falsepositive anti-HCV results with the Architect anti-HCV assay, 28 had sample value-to-cutoff (S/CO) ratios of less than 6 (22 had S/CO ratios between 1.3 and 2.54, 6 had S/CO ratios between 3.02 and 5.47), 7 had S/CO ratios of between 6 and 8, and only 3 had S/CO ratios of between 12 and 16. . . The diagnostic sensitivity, specificity, and positive and negative predictive values of the HCV Ag assay compared to the HCV RNA test were 96.3%, 100%, 100%, and 89.7%, respectively. (p. 2) SCREENING CAPSTONE PROJECT HCV 9 List populations or settings that the screening tests are commonly used for The populations that the HCV screening test are commonly used for is determined by risk factors. The settings that the HCV screening test are also generally determined by risk behaviors. See table one for a list of risk behaviors. In regards to screening, risk based screening has been unsuccessful in sufficiently identifying most individuals with HCV. This knowledge leads public health officials to promote one time cohort screening of baby boomers. Ethical considerations as a public health professional and specifically as an epidemiologist There are many ethical considerations. The populations at risk for HCV infection are often marginalized and stigmatized. The epidemiologist must be sensitive to the issues and concerns of the at risk population. The epidemiologist must also be sensitive to the issues and concerns that baby boomers have in addressing screening. The American culture can have a tendency to not want to cooperate with any type of foreseen mandatory testing. The ethics that have to be committed are the Five Principles of Morality. Recommendations What screening test would you recommend for your city/state and for what target population and in what setting. Why? I highly recommend expanding screening “to cover the birth cohort born from 1945 through 1965” which “offers a potential complement to current risk-based screening recommendations” (Rein et al., 2012, p. 1). One time “cohort screening is estimated to identify nearly 86% of undiagnosed cases compared with the 21% currently found through risk-based screening” (Jensen & Reau, 2013, p. 29). I recommend third generation EIA testing for the actual screening test. SCREENING CAPSTONE PROJECT HCV 10 The location of the testing site is important. I believe testing centers should be located where most people congregate and can receive testing. My recommendations are in alignment with the USPSTF which recommends screening for hepatitis C virus (HCV) infection in persons at high risk for infection and extending one-time screening for HCV infection to adults born before 1964 and after 1945 for the city of Detroit with a target population of Detroit residents who happen to be a majority of African Americans. Why? As stated earlier in this paper among people born before 1964 and after 1945, rates of Hepatitis C are higher in African Americans. African American baby boomers are twice as likely to have Hepatitis C as are other baby boomers (Dean, 2014). How you would you go about increasing the participation levels in the screening? Based on my recommendations I would advocate for more testing or screening during regular primary care visits. This would increase the participation levels. I would investigate culturally linguistic approaches to getting the message out concerning hepatitis c infection. I would increase funding to local health departments and community based organization emphasizing the need to prevent HCV infection. I would perform more research on the “test to treat model” focusing on HCV. It is good to be informed about the CDC’s initiative and the importance placed on HCV infection and the African American community. What role should public health play in increasing screening participation? The role that public health should play in increasing screening participation should include education, funding for local health departments, access to primary care facilities and drug treatment facilities. Public health should invest in innovative projects, as well. Social media should be explored as a means of increasing screening participation. SCREENING CAPSTONE PROJECT HCV 11 As we move towards curing HCV infection epidemiology stands in the forefront. “In clinical trials, antiviral therapy with pegylated interferon and ribavirin (PEG-IFN+R) has resulted in a sustained viral response (SVR) (that is, cure) of HCV infection in 46% of patients infected with genotype 1 (which infects 70% and 90% of chronically infected white and African American persons in the United States, respectively)” (Rein et al., 2012, p. 1). According to the American Association for the Study of Liver Diseases (AASLD) (2014, p. 1), “New direct-acting oral agents capable of curing hepatitis C virus (HCV) infection have been approved for use in the United States.” Therefore, as treatment improves screening or testing should be implemented with enthusiasm. Finally, there needs to more epidemiological, biomedical, and social and behavioral research undertaken. In the meantime, the data derived from morbidity and mortality sources are driving the motivation to continue and succeed. The goal is to improve the health of HCV infected persons and prevent further infections. In conclusion, I believe as a result of “The landscape of treatment for hepatitis C virus (HCV) infection [evolving] substantially” (American Association for the Study of Liver Diseases, 2014, p. 1) the screening for HCV should be strongly encouraged among the highly at risk and baby boomers with emphasis placed on African American baby boomers. SCREENING CAPSTONE PROJECT HCV 12 References American Association for the Study of Liver Diseases. (2014, January 29). Recommendations for Testing, Managing, and Treating Hepatitis C. Retrieved February 20, 2014, from http://hcvguidelines.org/ American Medical Association. (2013, March 20). Proteomics. Retrieved from http://www.amaassn.org//ama/pub/physician-resources/medical-science/genetics-molecularmedicine/current-topics/proteomics.page Centers for Disease Control and Prevention. (2013a, May 7). CDC DVH - Hepatitis C Information For the Health Professional. Retrieved January 31, 2014, from http://www.cdc.gov/hepatitis/hcv/ Centers for Disease Control and Prevention. (2013b, August 19). CDC DVH - Viral Hepatitis Statistics & Surveillance - Surveillance for Viral Hepatitis – United States, 2011. Retrieved February 1, 2014, from http://www.cdc.gov/hepatitis/Statistics/2011Surveillance/Commentary.htm#hepC Centers for Disease Control and Prevention. (2014, February 10). CDC DVH - Hepatitis C FAQs for the Public. Retrieved February 27, 2014, from http://www.cdc.gov/hepatitis/c/cfaq.htm#cFAQ54 Dean, H. (2014, February 21). Fighting Hepatitis C Among African Americans. blog.aids.gov — HIV Policy & Programs. Research. New Media. Retrieved from http://blog.aids.gov/2014/02/fighting-hepatitis-c-among-african-americans.html Jensen, D., & Reau, N. (2013). Hepatitis C. New York, N.Y.: Oxford University Press. Kesli, R., Polat, H., Terzi, Y., Kurtoglu, M. G., & Uyar, Y. (2011). Comparison of a Newly Developed Automated and Quantitative Hepatitis C Virus (HCV) Core Antigen Test with SCREENING CAPSTONE PROJECT HCV 13 the HCV RNA Assay for Clinical Usefulness in Confirming Anti-HCV Results. Journal of Clinical Microbiology, 49(12), 4089–4093. doi:10.1128/JCM.05292-11 Mayo Clinic. (n.d.). HCV - Clinical: Hepatitis C Antibody Screen, Serum. Retrieved February 12, 2014, from http://www.mayomedicallaboratories.com/testcatalog/Clinical+and+Interpretive/80190 Nelson, K. E., & Thomas, D. L. (2007). Viral Hepatitis. In C. M. Williams (Ed.), Infectious Disease Epidemiology: Theory and Practice (pp. 895–939). Sudbury, MA: Jones & Bartlett Learning. Parini, S. (2001). Hepatitis C: Speaking out about the silent epidemic. Nursing Management, 32(6), 18. Penin, F., Dubuisson, J., Rey, F. A., Moradpour, D., & Pawlotsky, J.-M. (2004). Structural biology of hepatitis C virus. Hepatology, 39(1), 5–19. doi:10.1002/hep.20032 Rein, D. B., Smith, B. D., Wittenborn, J. S., Lesesne, S. B., Wagner, L. D., Roblin, D. W., … Weinbaum, C. M. (2012). The Cost-Effectiveness of Birth-Cohort Screening for Hepatitis C Antibody in U.S. Primary Care Settings. Annals of Internal Medicine, 156(4), 263–270. doi:10.7326/0003-4819-156-4-201202210-00378 Rosenberg, S. (2001). Recent advances in the molecular biology of hepatitis C virus. Journal of Molecular Biology, 313(3), 451–464. doi:10.1006/jmbi.2001.5055 Schneider, M.-J. (2013). Introduction to public health. Jones & Bartlett Publishers. U.S. Preventive Services Task Force. (2013, June 25). Screening for Hepatitis C Virus Infection in Adults: Final Recommendation Statement. AHRQ Publication No. 12-05174-EF-2. Retrieved February 27, 2014, from http://www.uspreventiveservicestaskforce.org/uspstf12/hepc/hepcfinalrs.htm SCREENING CAPSTONE PROJECT HCV US National Library of Medicine, NIH, US HHS. (2013, September 23). What is a genome? Retrieved October 2, 2013, from http://ghr.nlm.nih.gov/handbook/hgp/genome Walzer, N., & Cotler, S. (2013). Diagnostic Testing. In Hepatitis C (p. 10). New York, N.Y.: Oxford University Press. 14 SCREENING CAPSTONE PROJECT HCV 15 Footnotes 1 Percutaneous is defined adjectively as administered, removed, or absorbed by way of the skin, as an injection, needle biopsy, or transdermal drug. 2 Parenteral is defined adjectively as taken into the body in a manner other than through the digestive canal or not within the intestine; not intestinal. SCREENING CAPSTONE PROJECT HCV 16 Tables Table 1 Risk Factors for HCV Illicit Drug or Intravenous Drug Use (IVDU) Person with high-risk sexual behaviors such as unprotected sex and multiple partners HIV-infected men who have sex with men (MSM) and engage in sexual behaviors that increase mucosal trauma Maternal-fetal transmission (especially among HIV-infected women) Blood transfusion Healthcare-related exposure to infected blood (needle stick injury, for instance). Table 2 Features of hepatitis C virus infection HCV RNA first detected in blood Time until symptoms (if any) Antibody first detected in blood Acute illness (jaundice) Chronic infection (mostly asx) Cirrhosis Mortality from Chronic Liver Disease 1-3 weeks Average 6-7 weeks Range 2-26 weeks In 50-70% at onset of symptoms; in 90% by 3 months Mild (< 20%) 75% - 85% 10% – 20% 1% - 5% Table 3 Diagnostic Testing Used in Patients with Hepatitis C Basic Laboratory Testing Serologic Assays Virologic Assays HCV Genotyping with Subtypes Complete metabolic panel Complete blood count Prothrombin time Anti-HCV RIBA HCV RNA nucleic acid testing (NAT) Quantitative Qualitative HCV core antigen EIA assay 1a-6 Source (all tables): Jensen, D., & Reau, N. (2013). Hepatitis C. Oxford University Press. SCREENING CAPSTONE PROJECT HCV 17 Figure Figure. Testing algorithm for hepatitis C (©2011, Natasha Walzer, MD)