In a new study published in Annals of Internal Medicine, researchers in Massachusetts found that less than 1% of acute cases of hepatitis C virus infection over the course of a decade in Massachusetts were reported to the CDC.
“The incidence of HCV can be likened to an ‘iceberg,’ in that only a fraction of cases — the proverbial ‘tip’ — is visible,” Arthur Kim, MD, division of infectious diseases, Massachusetts General Hospital, said in a press release. “That is due to the minimal symptoms that usually accompany acute HCV and the fragmented care available to those at highest risk, such as those who inject drugs. Many states have limited resources to track and identify HCV cases; and since even Massachusetts, where we have reasonable resources for HCV surveillance, found it difficult to report acute cases during the period we studied, it’s likely that national estimates have been based on inaccurate numbers.”
Kim and colleagues, including Shauna Onofrey, MPH, of the Massachusetts Department of Public Health (MDPH), conducted a case series and chart review using data from 183 patients with acute HCV enrolled in the Boston Acute HCV Study: Transmission, Immunity and Outcomes Network, between 2001 and 2011. The patients had been enrolled at either Massachusetts General Hospital or Lemuel Shattuck Hospital in Massachusetts. The researchers also looked at data from the Massachusetts Virtual Epidemiologic Network (MAVEN), a surveillance and case management system that allows state and public health care professionals to share data over the Internet, in which some of the cases were stored, according to the study.
“The Massachusetts surveillance system collects any evidence of HCV infection, allowing us to identify trends such as the epidemic of HCV in young people who inject drugs, despite this underestimation of acute infection,” Onofrey said in the release. “But in areas of the country where only acute HCV is reportable, this has likely delayed our understanding of the scope of this epidemic. Improved case definitions, along with continued partnership with health care providers to collect the necessary clinical information, will allow public health to better target resources to respond to this epidemic.”
Overall, 149 patients had been reported to the MDPH and entered in their database. Of the reported cases, 130 were labeled as having present or past HCV and 43 were investigated as possible HCV cases, according to the release. However, only one of the reported cases met all the criteria by the CDC to be considered a confirmed case.
“Only a single case fully met the definition of a confirmed reportable case, the others being disqualified because of factors such as the absence of specific symptoms or not meeting threshold lab test results,” according to the release.
Further analyses showed that of the cases not reported, 33 would have been reported to the CDC as acute HCV if all data had been made available to the MDPH.
The study also stated that 75 more cases met the surveillance case definition in 2012, which did not require negative hepatitis A virus or hepatitis B virus lab results and accepted a “documented negative anti-HCV laboratory test result followed within 6 months by a positive result regardless of clinical presentation.”
“Overall, I would argue that we should devote more resources to surveillance, so that we can better track cases as part of a comprehensive effort to prevent HCV and HIV infection in people who inject drugs,” Kim said. “Otherwise the costs — both personal and financial — of allowing these infections to spread and treating them in the future will be quite high.”
Kim also stated in the release that the MDPH has improved its reporting procedures by linking past test results with recent ones, in an effort to improve the way conversion from a negative to a positive HCV antibody status is captured. – by Melinda Stevens
Disclosures: Kim reports receiving grants from the NIH, personal fees from Bristol-Myers Squibb and grants and personal fees from AbbVie and Gilead Sciences. Please see the full study for a list of all other authors’ relevant financial disclosures.