Historians may look back on 2015 as a year of panic and progress in health and medicine. When 2015 dawned, West Africa was in the grip of an Ebola outbreak. This was the year of biologic drugs, one of which was credited with eliminating cancer in President Jimmy Carter’s brain. The Affordable Care Act entered its third year. We loved gut bugs but feared superbugs.

Here are the year’s most important health stories, in no particular order. We’ve included our coverage of these topics as well as some especially good stories from other publications .

Ebola Ebbs

More than 11,000 people died of Ebola in the 2014-2015 pandemic, which dominated the headlines through the first half of the year. Healthline reported on what critics called the World Health Organization’s scattershot response to the pandemic. But the deadly virus was nonetheless largely contained by February 2015. In April, a vaccine showed some early promise.

WHO Hammered By Task Force over Ebola Response, by Shawn Radcliffe for Healthline

The World Health Organization lacks the culture and capacity to deal with another global health crisis like the Ebola outbreak in West Africa, a task force report stated.

Leading Ebola Vaccine Candidate Succeeds in Phase One Trials, by Julia Haskins for Healthline

The rVSV-ZEBOV vaccine was effective and safe in dealing with Ebola in early-stage trials conducted around the world.

Ebola Crisis Eases in Africa. Now What?, by Shawn Radcliffe for Healthline

As the Ebola crisis appears to turn a corner in Africa, the international community has shifted from crisis mode to long-term planning.

Elsewhere:

2015 Resolution: Accept that Diseases Hop Borders, Don’t Dismiss Them, and Don’t Panic, by Maryn McKenna for Wired Magazine

The hysteria about Ebola wiping out the United States revealed the public’s naivete about our globalized world.

Ebola Wars, by Richard Preston for The New Yorker

How genomics research can help contain the outbreak.

Puzzling Ebola Death Shows How Little We Know About the Virus, by Jason Beaubien for National Public Radio

The death of a teenager in November Liberia confounded epidemiologists who can’t figure out how he got infected.

Gut Bugs and Superbugs

We really fell in love with the microbes in our bellies in 2015, hoping to find in them the missing puzzle piece for an array of health woes. But we were also spooked by other bacteria that seem to have learned to outsmart antibiotic drugs.

The Truth About C-Sections, Probiotics, and the Bacteria in Your Gut, by Heather Kathryn Ross for Healthline

Evidence is showing we can change our microbiome, the trillions of bacteria that have evolved to live inside us.

The Bacteria Will See You Now: How Little Bugs Cause Big Problems in Hospitals, by Brian Krans for Healthline

Hospitals are changing how they clean their rooms as concerns rise about the spread of dangerous drug-resistant bacteria in medical facilities.

Gut Bugs May Boost Immunotherapy for Cancer, by Shawn Radcliffe for Healthline

Two new studies show that bacteria in the intestines of mice may boost their immune system’s natural cancer-fighting abilities and the effects of immunotherapy drugs.

Elsewhere:

The Scientists Who Want to Fix Our Intestines Started With Their Own, by John Swanburg for New York Magazine’s The Science of Us

Much of the advice comes down to two basic ideas: Stop trying to sterilize your home as if it were a surgical theater and eat lots and lots and lots of fiber.

Rare Microbes and Antibiotic Resistance, by Jenny Rood for The Scientist

Members of a previously uncontacted Venezuelan tribe have the most diverse microbiomes yet described.

Among Trillions of Microbes in the Gut, a Few Are Special, by Moises Velsquez-Manoff for Scientific American

Amid the trillions of microbes that live in the intestines, scientists have found a few species that seem to play a key role in keeping us healthy.

Sugar Is the New Bad Guy

Obesity is one of the most significant health risk factors in the United States, especially for its role in the epidemic of type 2 diabetes. In 2015, researchers and nutritionists took aim at sugar as a primary culprit. It’s everywhere and it is bad for more than your teeth.

Evidence Shows Some Sugars Are Worse Than Others; Fructose Tops the List, by Cameron Scott for Healthline

Fructose and all added sugars are major drivers of type 2 diabetes, according to an analysis from the Mayo Clinic.

Sugar Industry Influenced Research on Tooth Decay, Documents Reveal, by David Mills for Healthline

The sugar industry worked closely with health organizations in the 1960s and early 1970s to develop dental policies that didn’t discourage children from eating sugar.

Yes, No, Maybe: Why is Nutrition Advice So Confusing?, by Cameron Scott for Healthline

It’s not just you. Diet science on basics like fat, sugar, and salt is confusing by design.

Elsewhere:

Where People Around the World Eat the Most Sugar and Fat, by Roberto A. Ferdman for The Washington Post

We all know Americans love their sugar. But data from market research firm Euromonitor suggest that the love may border on lunacy, at least compared with the rest of the world.

Man Gives Up Sugar and Alcohol for 1 Month, by BEC Crew for Life Hunters, via Science Alert

A video series that shows how hard it is to avoid sugar, and how the body withdraws when it doesn’t have as much as it craves. Things get ugly by Day 4.

How the Food Industry Helps Engineer Our Cravings, by Here & Now Staff for National Public Radio’s The Salt

The food industry has processed lots of foods to hit that "bliss point" — that perfect amount of sweetness that would send eaters over the moon.

Meat’s Connection to Cancer

There are plenty of health reasons not to eat animal protein, but now there’s a big new one: Strong evidence points to specific cancers tied to meat consumption. 

Bypass the Bacon and Skip the Steak to Lower Cancer Risk, by Cameron Scott for Healthline

Processed meat causes cancer and red meat probably does, too, according to the World Health Organization.

Colorectal Cancers Striking Younger People More Often, by Brian Krans for Healthline

Doctors are seeing more cases of colorectal cancer before the age of 50, the recommended age for screenings to begin. Risk factors include eating red meat and processed meat.

Elsewhere:

The Science Against Meat: A Look at 5 Key Studies About Cancer Risk, by Ariana Eugjung Cha for the Washington Post

Most of the studies focus on colorectal cancer, but scientists also looked at data for 15 other types of cancer and found positive associations for red meat and pancreatic and prostate cancer and of processed meat for cancer of the stomach.

A Look at Americans’ Reluctance to Accept Cancer Warnings, by Francie Diep for Pacific Standard

People often take too long to believe common habits can pose danger.

Bacon Causes Cancer? Sort Of. Not Really. Ish., by Sarah Zhang for Wired Magazine

Eating bacon is not as bad as smoking when it comes to cancer.

Biologic Drugs Show Big Promise, High Costs

Biologic drugs behave like elements of one’s own immune system but are programmed to perform  specific tasks such as blocking certain proteins. They have been widely used in autoimmune diseases such as rheumatoid arthritis for several years, but they are gaining a reputation for impressive results in other conditions, including cancer. But they don’t come cheap.

Rheumatoid Arthritis Patients Bear Heavy Cost Burden for Biologic Drugs, by Ashley Boynes-Shuck

Biologics are a common treatment for RA patients — but not a cheap one. On average, patients with rheumatoid arthritis can expect to pay $2,700 or more annually in copayments for biologic drugs.

Drug Used in Jimmy Carter’s Cancer Treatment Among a New Generation of Immune Therapies, by David Mills for Healthline

The medication is one of a new class of cancer-fighting drugs that are designed to encourage the body’s own immune system to attack cancers.

Immune Systems Now a Major Focus of Cancer Treatment Research, by Ann Pietrangelo for Healthline

Researchers are exploring patient-specific vaccines that would help the immune system fight wayward cancer cells.

Elsewhere:

The CAR T-Cell Race, by Vicki Brower for The Scientist

Tumor-targeting T-cell therapies are generating remarkable remissions in hard-to-beat cancers — and attracting millions of dollars of investment along the way.

He Had a 3.5 Pound Tumor and Months to Live. Here’s How He Survived, by Lenny Bernstein and Brady Dennis for The Washington Post

Today, immune therapies have quickly become the fourth pillar of cancer treatment, alongside surgery, radiation, and chemotherapy.

Cancer Immunotherapy: The Cutting Edge Gets Sharper, by Christine Gorman for Scientific American

What is the best way to kick the immune system into action? Will immunotherapy work for all sorts of people with all kinds of cancer or just for a lucky few?

Growing Focus on Health Disparities

Race, socioeconomic status, geography, gender, and other factors play an enormous role in an individual’s health. Why is that, and how can gaps between demographic groups be closed?

How Urban Planners are Trying to Detoxify Our Cities by Enabling Healthier Lifestyles, by Cameron Scott for Healthline

City governments are looking at ways to influence Americans’ well-being by making the healthy choices easier to achieve. 

Why More Non-White Doctors Are Needed, by Cameron Scott for Healthline

Non-white patients have poorer health and get less effective care than white Americans. The problem is complicated, but part of the answer is simple: more minority doctors.

Hepatitis Outbreak in Appalachia Blamed on Poverty, Drug Use, by Kristen Fischer for Healthline

Experts say the problem is fundamentally a societal one. The region is extremely poor and drug use follows poverty.

Elsewhere: 

Being Black Can Be Bad for Your Health: Race, Medicine, and the Cruelest Unfairness of All, by Damon Tweedy for Salon

“Of all the forms of inequality,” Martin Luther King Jr. told a gathering of the Medical Committee for Human Rights in 1966, “injustice in health is the most shocking and the most inhumane.”

The Quality of Health Care You Receive Likely Depends on Your Skin Color, by Erin Shumaker for the Huffington Post

More than any other single group, the black community is most likely to have negative health outcomes, including higher rates of breast and prostate cancer, high incidence of HIV/AIDS, higher rates of infant morality — along with high rates of childhood obesity, and asthma in young adults.

Genes Don’t Cause Racial Health Disparities, Society Does, by Jason Silverstein for The Atlantic

White people live longer, not because of their DNA, but because of inequality.

The Affordable Care Act

Known colloquially as “Obamacare,” the ACA entered its third year having survived Congressional challenges and growing pains. We looked at what has worked and what has not as well as some unforeseen consequences, such as skyrocketing premiums and tussles over coverage of high-priced drugs and procedures.

Scoring Obamacare After Two Years, by Cameron Scott for Healthline

More Americans have health insurance and access to care, but millions are still left in the lurch.

Is It True? Do Doctors Really Loathe Obamacare? By David Mills for Healthline

Doctors in the United States appear as bitterly divided over the Affordable Care Act as the general public.

This Is What Your Doctor’s Office Will Look Like in Five Years, by David Mills for Healthline

Healthcare costs, new technology, and a physician shortage are driving changes that will alter where you go to see the doctor, how you’re cared for, and how much it costs.

Elsewhere:

The Anatomy of Obamacare, by Malcolm Gladwell for The New Yorker

A dysfunctional healthcare system gets a fragmented and dysfunctional makeover. A patchwork of compromises, a review of the birth of Obamacare as detailed in Steven Brill’s “America’s Bitter Pill.”

The Federal Health Care Law: What Came True and What Didn’t, by Steve Contorno and Angie Drobnic Holan for Politifact

Obamacare supporters contended that virtually everyone around the country would soon have access to affordable insurance. Opponents said the law would cost a fortune by adding to the national debt and killing jobs. Actually, none of those things have happened.

PPOs Are Disappearing From Obamacare. Why? by Helaine Olen for Slate

Health plans that will pay for out-of-network care are disappearing from the insurance exchanges.

Inflammation and Autoimmune Disease

Autoimmune diseases are more prevalent than ever, a challenge for researchers and doctors who have trouble pinpointing how these types of disease begin and how to stop them. Inflammation gained traction as a way into understanding autoimmune conditions. But does it cause these conditions, result from them, or both?

We May Be Closing In on the Causes of Autoimmune Disease, by Nina Lincoff for Healthline

An original infection may leave scars on the lymph nodes or the immune system, leading to autoimmune diseases such as rheumatoid arthritis.

Scientists Cure Lupus in Mice With a One-Two Punch, by Nina Lincoff for Healthline

Researchers say the key to reversing lupus may be a combination of two drugs already on the market.

Why Rheumatoid Arthritis is Plaguing 9/11 First Responders, by Ashley Boynes-Shuck for Healthline

Ground zero workers from the Sept. 11 terrorist attacks have suffered from many health problems. Now rheumatoid arthritis and similar conditions have been added to their list of potential woes.

Elsewhere:

Inflamed, by Jerome Groopman for The New Yorker

“[S]everal lines of research have revealed that low-level inflammation can simmer quietly in the body, in the absence of overt trauma or infection, with profound implications for our health.”

Body, Heal Thyself, by Jason Liebowitz for The Scientist

“[T]here remains an entire class of illnesses that present systemically, do not respect the boundaries of organ systems, and wreak havoc on quality of life and longevity. And we still have little idea of what starts the vicious cascade in the first place.”

We Can Edit Genes Now

The world has anticipated — and feared — the day when we could freely edit our DNA. That day seems to be here, and with it comes the promise of curing certain genetic diseases and cancers, but also ethical fears about everything from designer babies to eugenics.

Harvard, MIT Make Controversial Gene-Editing Tool More Powerful, by Shawn Radcliffe for Healthline

Scientists have overcome a major obstacle to precisely editing human DNA. But the ethical questions can’t be ignored.

Scientists Find Gene Editing with CRISPR Hard to Resist, by Cameron Scott for Healthline

The new technique for editing DNA is so cheap and easy to use, we may be genetically engineering human embryos before we have time to decide if we should. 

New Technology Expands Gene Editing Therapies to Fight Cancer, by Brian Krans for Healthline

After an infant is cured of a deadly form of leukemia, researchers are exploring the use of cancer-fighting cells derived from a single donor.

Elsewhere:

Easy DNA Editing Will Remake the World. Buckle Up. by Amy Maxmen, Wired Magazine

“The technique is revolutionary, and like all revolutions, it's perilous. ... It could at last allow genetics researchers to conjure everything anyone has ever worried they would—designer babies, invasive mutants, species-specific bioweapons, and a dozen other apocalyptic sci-fi tropes.”

Watch Science Writer Carl Zimmer Explain CRISPR in 90 Seconds, by by Alex Kuzoian and Jessica Orwig for Business Insider

Gun Violence, The American Epidemic

Gun violence grabbed the headlines this year. Aside from the obvious political arguments, mass shootings and persistent urban violence have renewed calls for a public-health approach to minimizing the physical and psychological injuries caused by our national epidemic of gun violence.

Approaching Gun Violence As a Public Health Issue, by Shawn Radcliffe for Healthline

Mass shootings are up, but gun violence overall is down. Still, in some regions it represents a persistent threat to communities’ physical and emotional health, and some experts say it’s as much a public-health issue as air pollution or second-hand smoke.

Police Involved Shootings Should Be Counted in Public Heath Data, by Shawn Radcliffe for Healthline

With a lack of reliable data on the number of people killed in the United States by police officers, a group of researchers calls for public-health agencies to track these deaths, alongside police killed on the job.

Preventing Suicide, One Blister-Pack and Bridge Barrier At a Time, by Cameron Scott for Healthline

Most deaths involving guns are suicides. Because suicide is often impulsive, restricting access to the means of self-destruction can save lives.

Elsewhere:

Thresholds of Violence, by Malcolm Gladwell for The New Yorker

How mass shootings can become contagious, and new insights into the psychology of people who commit violent or destructive acts that seem wildly out of character.

Gun Violence is a Public Health Issue. So Why Isn’t the CDC Researching It? by Martha Kempner for RH Reality Check

The CDC operates under a congressional prohibition — first passed in the 1990s — that prevents the agency from undertaking in-depth research on gun violence.

The Mental Illness Myth: People Like Me Aren’t the Cause of America’s Mass Shooting Epidemic, by Sarah Fader for Quartz

“When someone walks into a school and opens fire with semiautomatic weapons, we can’t just say ‘mental illness,’ shrug our shoulders and walk away. Nor can we scream ‘mental illness’ and start pointing fingers. The reality is this: Most people living with mental illness are not dangerous, and each mass shooting seems to bring us dangerously closer to equating the two.”

Mainstreaming Marijuana

Several years after cannabis was legalized for medicinal use in several states, Oregon joined Colorado in 2015 to become the second state to legalize pot for recreational use. But the United States, and science, is still divided about the legitimate benefits of marijuana and whether they outweigh any of the drug’s risks.

If Marijuana is Medicine, Why Can’t We Buy It in Pharmacies? by Cameron Scott for Healthline

Medical marijuana is more readily available thanks to a spate of new state laws. But there’s nothing medical about the path most patients take to get it.

Pot’s Hot: Marijuana Use Has Doubled Since 2001, by Shawn Radcliffe for Healthline

The reason for weed’s soaring use and abuse remains hazy.

Will Marijuana Follow in the Footsteps of Big Tobacco? by Shawn Radcliffe for Healthline

As marijuana legalization continues, experts are watching to see if pot producers will follow the practices of cigarette manufacturers.

Drug Prices Explode

Thrust back into the mainstream media’s glare by “pharma bro” Martin Shkreli of Turing Pharmaceuticals, drug prices were a hot topic in 2015. Exciting new therapies and more widespread insurance coverage across the United States means we should be healthier than ever. But the cost of a cure seems to keep going up.

Why Some Drugs Cost So Much, And Others Don’t, by Jamie Reno for Healthline

Experts say greed is a big reason for the sky-high price of some prescription pills. But it’s not the only one.

MS Drug Prices Soar; Neurologists Encouraged to Fight Back, by Jeri Burtchell for Healthline

The pharmaceutical industry may be forced to put the brakes on MS drug pricing as Americans grow weary of paying the cost.

Massive Trade Pact Could Inflate Global Drug Prices, by Brian Krans for Healthline

Those familiar with the agreement say it will create or extend pharmaceutical monopolies. That, they say, will lead to increased drug costs and undue suffering.

Elsewhere:

Drug Prices Are Too Damn High. Here’s How to Fix Them, by David Wolman for Wired Magazine

“[T]here are steps we can take to reel prices in. First is shifting away from monopolistic pricing to a more competitive model. Second is designing mechanisms that link the cost of drugs to the value delivered to patients, insurers, society, and even science.”

Doctors Seek Ban On Prescription Drug Ads, by Alexandra Ossola for Popular Science Magazine

All these ads have shifted the market in a way that isn’t helpful to consumers, the AMA argues. ”Physicians cited concerns that a growing proliferation of ads is driving demand for expensive treatments despite the clinical effectiveness of less costly alternatives.”

The Drugs Cost Too Damn Much, by Kate Wheeling for Pacific Standard

Why are prescription drugs, like ipilimumab, so expensive?

Smoking, Electronic Cigarettes, and Vaping

Smoking is down in the United States, but it’s still a significant health problem. The advent of electronic cigarettes and other devices that claim to deliver nicotine without all the harmful chemicals of cigarettes has been met with scientific skepticism.  There’s still way too much we don’t know about what’s in that vapor.

Half of U.S. Cancer Deaths Linked to Smoking In New Study, by Kristen Fischer for Healthline

Nearly half of the cancer deaths reported in 2011, including deaths from bladder, colon, and liver cancers, were the result of cigarette smoking. 

Electronic Cigarette Flavors Contain Lung-Corroding Chemicals, by Brian Krans for Healthline

New reports suggest e-cigarette flavors geared toward young people carry serious risks of lung damage, including a condition known as ”popcorn lung.”

E-Cigarettes Hurt Instead of Help Efforts to Quit Smoking, by Cameron Scott for Healthline

Proponents say e-cigarettes can help in the fight against cancer by providing smokers a way to quit. A new study suggests they’re wrong.

Elsewhere:

The Dangers of Electronic Cigarettes, by The Skeptical Raptor

Love him or hate him, science’s snarkiest skeptic takes down both sides of the e-cigarette culture wars by looking at the evidence in quality, peer-reviewed studies.

E-Cigarette Facts You Need to Know, by Laura Blue for Consumer Reports

The bible of independent reporting on consumer products concludes that yes, e-cigs are bad for you.

The Poison in Your E-Cigarettes, by Abby Haglage for The Daily Beast

If you think e-cigs are a safer alternative to regular cigarettes, think again.

PrEP — The Beginning of the End of HIV?

This year, we marked another major turning point in the history of HIV/AIDS: a single pill, taken once a day, that successfully prevents infection in most cases. Alternately called by its brand name, Truvada, or PrEP, short for pre-exposure prophylaxis, the regimen could mark the end of the virus’ stranglehold on thegay community. But distrust of the pharmaceutical industry and healthcare access woes are slowing adoption in the U.S. In Africa, the drug remains almost entirely out of reach.

Head-to-Head Studies Show Truvada Prevents HIV Even When Taken ‘As Needed’, by Heather Ross for Healthline

Studies showed that Truvada can prevent HIV infections in a real-world setting, boasting an 86 percent reduction in new HIV infections among volunteers.

Does Taking PrEP Encourage Risky Behavior?, by David Heitz for Healthline

Does the medication Truvada, taken daily to prevent HIV infection, encourage those who take it to have risky sex or use drugs?

Daily Pill That Prevents HIV Infection Not Reaching Enough People Globally, by Shawn Radcliffe for Healthline

Information from some major cities shows that many high-risk individuals are still not taking advantage of PrEP. 

White House Wants to Boost Access to PrEP in U.S., by Kristen Fischer for Healthline

HIV-awareness groups say providing better access to the drug is essential to lower the rate of infection.

Elsewhere:

How PrEP Is Being Blocked By Bureaucracy, by Xorje Olivares for The Advocate

Bureaucracy and deliberate attempts to block prevention techniques are slowing down Los Angeles’ ability to disseminate PrEP.

Stopping HIV? The Truvada Revolution, by Vice Reports

Controversy continues to surround the broad uptake of Truvada, but the landscape of safer sex and HIV prevention changes fundamentally from this point forward — particularly within the gay male community, the population hit hardest by HIV in the United States.

Can This Pill End the AIDS Epidemic?, by Ben Tinker for CNN

When taken as prescribed, PrEP can prevent more than 90 percent of sexually transmitted HIV infections. So why aren't people jumping on the bandwagon?