Study: IV Drug Users Are ‘Super-Spreaders’ of HCV Infections

According to a new study published January 31st, 2013, in the Journal PLOS Computational Biology, a team of researchers from Oxford University, the University of Athens and Imperial College have developed a protocol for identifying how the initial spread of viral infections, with the HCV infection used as a model, are spread over a specific time frame, becoming secondary infections which multiply the number of HCV infections exponentially.

Lead study author Dr. Gkikas Magiorkinis and his team of researchers have evaluated data using a novel method, combining epidemiological and genetic information to estimate the different variations in the transmission of rapidly evolving viral epidemics. This methodology was used with regards to the nationwide HCV epidemic to evaluate secondary transmission and the super-spreading of the HCV infection, identifying target individuals and control strategies to be put forth towards these “super-spreaders” of the HCV virus.

“For the 1st time we show that super-spreading in hepatitis C is led by intravenous drug users early in their infection” said Dr. Magiorkinis. “Using this information, we can hopefully soon make a solid argument to support the scaling up of early diagnosis in antiviral treatment and drug users,” adding, “helping these people and stopping the spread of hepatitis C is our ultimate target.”

In scientific circles, the secondary spread of infectious diseases is generally referred to as the “20 – 80” rule, meaning that 20% of initial infections result in 80% of infections beyond that.

“Super-spreaders” is the term now being used for the clusters of infected persons that re-introduce these infections disproportionately amongst the general population.

“Working out how many people are likely to be infected by each ‘super spreader’ of hepatitis C, as well as how soon they will be infected, has been a puzzle for over 20 years,” said Dr. Magiorkinis, adding, “our research has resolved this issue and paves the way for a modeling study to show what kind of public health interventions could really make a difference.”

Hepatitis C is a viral infection that attacks the liver, and heavy alcohol use, drug abuse, certain diseases, and bacterial and viral infections are major causes of hepatitis. Hepatitis is described as a family of viral infections that affect the liver, the most common are hepatitis A, hepatitis B, hepatitis C.

Acute hepatitis C viral (HCV) infections can initially present as a mild illness that only lasts several weeks, and is characterized as a short-term illness that normally occurs within the 1st 6 months after someone contracts HCV. If treatment is not sought quickly, this infection usually leads to chronic, long-term HCV.

Chronic hepatitis C viral infections are much more serious in scope and nature, and generally morphed from acute hepatitis C when no treatment is sought early. The infection can last a lifetime and causes serious liver problems including cancer and cirrhosis of the liver.

The Centers for Disease Control and Prevention in Atlanta, Georgia (CDC) has estimated that 16,000 cases of acute hepatitis C viral infections were reported in the United States in 2009.

Again according to the CDC, it is estimated that there are more than 3 million people in the United States that have a chronic HCV infection, with roughly 80% of people with an acute case of HCV progressing to a chronic infection of HCV.

The HCV viral infection can be spread through blood transfusions, organ transplants, but more than likely is spread through IV drug use and the sharing of needles to inject drugs. Additionally women with the hepatitis C virus transmit the virus to their unborn children, and these newborns generally have HCV upon birth.

Symptoms of acute HCV infection are:

  • Fever.
  • Fatigue.
  • Loss of appetite.
  • Nausea.
  • Vomiting.
  • Abdominal pain.
  • Dark urine.
  • Clay colored bowel movements.
  • Joint pain.
  • Yellow jaundice.

Symptomology is not always apparent, but normally symptoms develop anywhere between 2 weeks to 6 months.

Those at greatest risk for contracting HCV are:

  • Current or former IV drug users.
  • Those receiving blood transfusions or organ transplants.
  • Hemodialysis patients.
  • Persons receiving tattoos or body piercings.
  • Healthcare providers injured by inadvertent needle sticks.
  • Newborn infants whose mothers have HCV.
  • HIV/AIDS infected persons.

Here are some staggering figures from the CDC regarding the long-term effects of an HCV infection.

In most cases, 75 to 85 people with acute HCV will develop chronic HCV, 60 to 70 people will go on to develop chronic liver disease, 5 to 20 people will go on to develop cirrhosis of the liver over an extended period of 20 to 30 years, and 20% of people will die from cirrhosis of the liver or liver cancer.

That means that 1 in 5 people with a chronic HCV infection will die from liver related issues.

Dr. Gkikas Magiorkinis is a Marie Curie Research Fellow and a MRC Clinician Scientist Fellow (2013) in the Department of Zoology at the University of Oxford, Oxford, U.K., and is affiliated with the Department of Hygiene, Epidemiology and Medical Statistics, University of Athens, Greece.

There is no Vaccination available to prevent an HCV infection.

Jim Donahue

Sources / Links / References

You must be logged in to post a comment Login