Can you think of a single week in 2013 where health care wasn't a major news item? Me neither.

In many ways, the past year was one of the most significant in a long time for the health care industry. A lot happened that could shape the American landscape for years to come. Here are the three biggest health care stories of the year.

3. Biotech boom 
2013 stands out as the greatest year for biotech in the 21st century so far. The iShares Nasdaq Biotechnology ETF skyrocketed 58%. That's nearly twice the gains of the second-highest year: 2012, when the exchange-traded fund jumped 32%. These kind of incredible returns tend to happen when the worst of an ETF's top 10 holdings increase 28% in value.

Smaller biotechs emerged as the year's biggest winners. Inovio Pharmaceuticals Inc. (INO -2.07%) is one great case in point, with shares soaring 330% in 2013. Investors' excitement grew in 2013 over Inovio's synthetic DNA vaccines, including the cervical dysplasia vaccine now in a midstage clinical study.

Big biotechs weren't left out of the frenzy, though. Shares of Celgene Corporation (CELG), for example, more than doubled this year. Blockbuster drug Revlimid continued to power Celgene's growth. However, the company also benefited from its bench with Abraxane gaining strength and good news from the pipeline with Pomalyst's approval.

2. Hepatitis C race
Perhaps the most promising catalyst for part of the biotech boom in 2013 stemmed from a frantic race among several players to reach the market with an all-oral treatment for the hepatitis C virus, or HCV. About 3.2 million Americans have chronic HCV infection, but good news should soon be on the way for these individuals.

AbbVie Inc. (ABBV -0.60%) has been one top contender in the race. Halfway through 2013, the company maintained that it could emerge as the leader of the pack with its multidrug HCV regimen. Just a few weeks ago, AbbVie reported great news from a late-stage clinical study that found 96% of patients were cured after taking its all-oral treatment.

In the last several days, though, AbbVie's primary rival, Gilead Sciences, Inc. (GILD -2.10%), appears to have grabbed a solid lead. On Dec. 18, Gilead announced positive results from three late-stage clinical studies for an all-oral combo featuring Sovaldi -- a 99.1% cure rate after 24 weeks of treatment. The Sovaldi ribavirin-free regimen only requires patients to take one pill once a day, versus six pills per day including ribavirin and another four pills without ribavirin with AbbVie's therapy.

1. Obamacare
The hands-down biggest health care story of 2013, though, is the ongoing saga of the implementation of the Affordable Care Act, commonly known as Obamacare. Nearly every week brought another story about the impact of the landmark health reform legislation.

UnitedHealth Group Inc. (UNH 1.57%) took a spot at the center of the Obamacare drama. The nation's largest health insurer decided to stay away from most state health exchanges early in 2013, citing concerns about an initial wave of less healthy (and less profitable) enrollees. UnitedHealth, though, did stand to benefit considerably from the Medicaid expansion fostered by the Affordable Care Act.

The biggest Obamacare news of all, however, was the disastrous launch of the HealthCare.gov website. Those woes of the online insurance marketplace covering 36 states resulted in enrollment numbers that were downright ugly, leading to a big damage-control effort by the federal government and multiple delays in provisions of Obamacare. And UnitedHealth played a major role, with its Quality Software Services unit serving as one of several major contractors involved in initial development of the website and as the lead contractor in the remedial work.

Legs into the future?
One of the first questions news industry insiders ask when a story first breaks is whether it will "have legs" -- that is, will the story continue to attract interest for a long time. Will our biggest health care stories from 2013 have legs into the new year? I think so.

It is entirely possible (maybe even probable) that the great biotech boom of 2013 will subside somewhat in 2014. However, I suspect that we'll continue to see strength from the sector. Too many companies are developing too many promising drugs for biotech's appeal to completely fizzle out.

And while the harried hepatitis C race of this year will see a conclusion in 2014, probably with Gilead emerging as the winner, the results of that race will be long-lasting. Millions of HCV patients across the world will benefit from the new drugs hitting the market.

We don't even have to guess whether Obamacare will continue to be a huge story next year: it will. Exactly how that story unfolds is a different question altogether. Obamacare might ultimately prove successful, or it could eventually completely unravel. Next year will be yet another fun time to watch health care.

The biggest stock of 2014?