Source: European Commission DG ECHO via Flickr

Infectious diseases are everywhere, and according to Smart Global Health they're blamed for 16% of global deaths each year. Breaking these deaths down based on data from the World Health Organization, these include close to 4 million respiratory infection deaths annually (e.g., pneumonia), malaria -- which can claim up to 3 million lives per year -- HIV and AIDS, which account for roughly 2.5 million deaths, and tuberculosis, which is the primary cause of death for about 1.7 million people annually. 

Right now the disease everyone's paying attention to is Ebola, a virus that presents with flu-like systems but can have serious, and often fatal, consequences. But putting things into context Ebola hasn't become a huge global killer. Thus far the death toll has crossed 4,000. This is a saddening figure, but it pales in comparison to the annual death toll from HIV/AIDS or tuberculosis, for example.

180 million have this disease, but few know it!
There is, however, another deadly disease in existence that, based on data from the World Health Organization, affects an estimated 180 million people, or 3% of the world's population. Though it may not be as lethal as Ebola in terms of how quickly it kills it victims, this global disease can, in its chronic state, lead to liver damage, liver disease, liver cancer, or even death. Within just the U.S., it's a disease that claims 15,000 lives annually.

Now here's truly scary aspect of this disease: most people have no clue they have it. According to the Centers for Disease Control and Prevention, 75% of disease carriers are unaware they're sick until the disease has progressed into its later stages. Extrapolating that figure out globally, this would mean in the neighborhood of 135 million people could have this potentially deadly disease and yet may be completely unaware of it. 

This mystery disease is none other than hepatitis C.

Source: Centers for Disease Control and Prevention

As the CDC also notes, needle or syringe sharing, needlesticks in the health care setting, or being born to a mother who had hepatitis C are the most common ways of spreading the disease, though less common methods, such as sharing personal care items like a razor, or through sexual contact with an infected person can also potentially spread the disease.

Here's the good news
The above data isn't very encouraging. If anything the prospect of living with a potentially deadly disease which can manifest and spread over time without you knowing it can be borderline scary. However, there's good news as well.

Though I tend to shy away from using the word "cure" as it doesn't clear up all cases of hepatitis C, there is a relatively new drug on pharmacy shelves in the U.S. that has a very high success rate of eradicating hepatitis C in many patients. In addition, there are considerably easier methods now that patients can use to find out whether or not they're infected with hepatitis C. In other words, with better diagnostic equipment and improved pharmaceutical products, it's possible that in a decade or two we'll no longer be talking about hepatitis C as a lethal disease.

Let's have a quick look at two companies at the forefront of its potential eradication.

Leading the charge
On the diagnostic front OraSure Technologies (NASDAQ:OSUR) is leading the charge with its extremely rapid OraQuick antibody test. Using a fingerstick's worth of blood, the OraQuick device allows health care providers to deliver a positive or negative hepatitis C diagnosis to patients in just 20 minutes.

Source: OraSure Technologies

Based on OraSure's claims, the device will test for multiple HCV genotypes (there are quite a few hepatitis C genotypes, of which genotype 1 is the most common), and it's accurate more than 98% of the time. This is a potentially revolutionary diagnostic tool that could one day be used throughout the world to quickly assess whether patients' are disease positive or negative and get them the appropriate treatment based on their initial diagnosis.

Within the U.S. hepatitis C is the greatest threat for those born between 1945 and 1965, largely because blood-screening technology prior to 1992 wasn't as thorough as it is today. With that in mind, states like New York allow select residents, including those born between 1945 and 1965, to get a free hepatitis C test once in their lifetime. What test is being used? You guessed it; OraQuick's HCV antibody test! 

A long time coming
Perhaps an even greater innovative marvel, and a true testament to pharmaceutical research, is the development of Gilead Sciences (NASDAQ:GILD) hepatitis C drug Sovaldi. While the drug itself has taken heat from patients and Congress for its exorbitant price tag ($1,000 per day for 12 weeks, or $84,000), there's little denying that it's delivered a drastic improvement in patient quality of life and in disease eradication.

Prior to Sovaldi the go-to hepatitis C drug was Vertex Pharmaceuticals' (NASDAQ:VRTX) Incivek. Incivek was an oral pill that was given with intravenous interferon. In studies it dramatically boosted the sustained virologic response of patients (essentially the level at which the disease is undetectable), but it often came with nasty flu-like side effects vis-a-vis the interferon.

Source: Gilead Sciences

Sovaldi is a completely different beast. It's an oral medication that can be given to genotype 2 and 3 patients without the need for interferon, thus eliminating many of the nasty side effects noted with hepatitis C treatments. Furthermore, Sovaldi successfully eliminated detectable levels of the disease in 76% to 92% of patients or higher, just depending on the study and whether or not a ribavirin was also administered. The SVR's were notable higher in genotype 1 patients. Simply put, this is a highly effective therapy at ridding patients of hepatitis C -- and it's potentially getting even better. 

Just last week Gilead announced that the Food and Drug Administration had approved Harvoni, which is a combination of Sovaldi with ledipasvir to treat genotype 1 patients without the need for interferon or a ribavirin. Over three phase 3 studies the once-daily (and costly) pill achieved a cure rate of 94% to 99%. Furthermore, it shortened the treatment duration for treatment-naive patients to just eight weeks. Forget taking steps forward; Gilead Sciences jumped from practically the middle of the board to nearly the finish line in one move!

This therapy is a long time coming, but it has the potential to pay big dividends in the fight against hepatitis C.

Source: Centers for Disease Control and Prevention

Here's what really matters
Hepatitis C may not be on many people's radar because of the relatively slow progression of the disease, but it clearly affects a sizable percentage of the global population, and even more importantly, millions are clueless they have the disease. It would appear we now have the tools necessary to combat the disease as long as medical organization worldwide work together to combat this hepatitis C. With Ebola taking precedence at the moment that might be tough. However, over time I strongly believe we'll see a concerted effort to boost testing around the globe as well as increase access to these life-saving medications.

Soon we could be living in a world without hepatitis C. At least that's my hope.

Sean Williams has no material interest in any companies mentioned in this article. You can follow him on CAPS under the screen name TMFUltraLong, track every pick he makes under the screen name TrackUltraLong, and check him out on Twitter, where he goes by the handle @TMFUltraLong.

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