All adults age 18 and older should be screened for
hepatitis C virus (HCV) infection at least once in their lifetime, while women
should be screened during every pregnancy, say new U.S. Centers for Disease
Control and Prevention (CDC) recommendations.
These latest
recommendations, published on April 10, 2020, expand CDC's 2012 call for
one-time HCV screening of all baby boomers, adults born from 1945 through 1965,
along with people of any age with certain risk factors. This group includes
injection drug users, dialysis patients, people with HIV, children born to
mothers with HCV, and incarcerated people, among others. Individuals with any
ongoing risk should be screened for HCV periodically, according to the
CDC.
The new recommendations do not apply in areas of the U.S. where less
than 0.1% of adults have HCV infections, says the CDC. However, no U.S. state
currently meets this criterion.
HCV and screening
Most often transmitted
by intravenous drug users sharing needles, HCV causes the liver infection
hepatitis C. Less commonly, the virus is spread via sexual contact, unregulated
tattooing, needlestick injuries in healthcare workers, and from mothers to
babies during pregnancy or childbirth.
For some people, infection with HCV is
a short-term illness (called acute hepatitis C), usually with few, mild symptoms
or no symptoms, and the virus is cleared from the body without specific
treatment. Occasionally, this acute stage of infection can cause more severe
symptoms, particularly jaundice and fatigue. However, more than half of people
infected develop chronic hepatitis C that, without treatment, can lead to
serious, long-term health problems like cirrhosis and liver cancer, and may be
fatal.
Chronic hepatitis progresses slowly over time, so infected individuals
may not be aware they have the condition until it causes enough liver damage to
affect liver function. Screening of all adults, including those without
symptoms, enables earlier diagnosis and allows healthcare practitioners to
properly treat chronic HCV infections and monitor infected patients' liver
function more closely.
The most common HCV screening test looks for
antibodies in the blood, produced in response to an HCV infection.
Because
someone can have positive results on an antibody test even if the infection is
cleared, healthcare professionals may order a hepatitis C RNA test, which
detects the virus's genetic material. In some cases, this test is done
automatically the first time antibodies to HCV are noted in the blood. A
positive result on the RNA test means the virus is present, the infection has
not resolved, and the person will likely require treatment.
Another test,
called the hepatitis C genotype test, identifies the strain of virus and can
help healthcare professionals choose the right treatment.
Healthcare
professionals may also order other tests that help assess the health of the
liver.
Infections Skyrocket, Especially Among Young Adults
A CDC report
issued along with the screening recommendation provides a rationale by
highlighting a very sharp rise in acute hepatitis C infection and subsequent
risk of chronic disease among young adults.
The report says the total number
of reported acute hepatitis C cases tripled from 2009 to 2018 and was highest
among people ages 20–39. Their rates of acute infection increased about 300%
during the period. Among adults ages 30 to 39, rates increased about 400%,
according to the report. In 2018, the largest proportion of chronic hepatitis C
cases occurred among people ages 20–39 and those ages 50–69, who had almost
equal infection rates. Only about 61% of adults with hepatitis C knew that they
were infected.
"These findings highlight the need for immediate
implementation of the new CDC universal hepatitis C screening recommendations
for all adults and pregnant women," the report notes. "Diagnosing HCV infection
is a necessary first step to linking persons to cure to prevent life-threatening
consequences of long-term chronic infections and transmission to others."
The
updated CDC hepatitis C screening recommendations are similar to but wider in
scope than new guidelines from the US Preventive Services Task Force (USPSTF)
that were finalized on March 2, 2020. In contrast to the CDC's call for
screening all adults, the USPSTF established more specific age criteria,
recommending HCV screening for adults ages 18-79, along with others at high
risk. Also, the USPSTF does not address screening women during pregnancy. (For
more, read U.S. Task Force: All Adults Should be Screened for Hepatitis C.)