Millions of lives were saved in the 2010s as new ways of tackling global health problems made their debut.

But there is a problem with the decade's greatest medical moments. Most medical advances originate in rich countries, so they are sometimes out of reach for the world's poor — even when they address health problems more common in low-income countries. Treatment for HIV, for example, became available in the U.S. in 1996 but the rollout in Africa didn't begin until 2002.

But some breakthroughs of the past decade have gone on to have a truly global impact.

Here's a sampling that literally broke through those walls of affordability and availability to save millions of lives around the world.

A drug puts the end of AIDS in view

"If you ask me what's the greatest development in HIV/AIDS in the last ten years, it's the drug dolutegravir," says Dr. Max Essex , professor emeritus at the Harvard T.H. Chan School of Public Health.

The drug can reduce the amount of virus in the blood to levels so low that it's undetectable. When HIV can't be detected in a patient's blood, it can't be transmitted to a sexual partner, a concept proved in the 2010s. Dolutegravir has been the first-line treatment in the U.S. and Europe for HIV patients since 2014. It's taken just once a day, and unlike other AIDS drugs, if patients occasionally forget a dose, the drug doesn't stop working.

"It's the first AIDS drug where drug resistance wasn't an issue," Essex says. "Botswana started using dolutegravir in 2016, and in time probably everybody will use it." Poor countries may take longer to adopt the new drug because of inadequate health infrastructure, governments unresponsive to the epidemic or economic constraints.

The same AIDS drugs that prevent transmission between sex partners also protect infants from getting HIV through breast milk, says Essex, so now HIV-infected women in poor countries can safely breastfeed their infants.

Before 2010, says Mitchell Warren , executive director of AVAC (AIDS Vaccine Advocacy Coalition), no one talked about ending the AIDS epidemic. Drugs like dolutegravir changed that.

"We all dreamed of a world without AIDS, but never thought it would happen in our lifetime," he says. "We're now talking about it."

Ebola crisis speeds up vaccine research

A scientific triumph came out of the tragedy of Ebola outbreaks in the last decade, says Dr. Daniel Bausch , director of the UK Public Health Rapid Support Team at the London School of Hygiene and Tropical Medicine. Before the 2014-2015 Ebola outbreak in West Africa, "we had accepted that clinical trials for drugs and vaccines were 10-year efforts, but with the West Africa outbreak, we found a new speed for clinical trials," he says.

Clinical trials have three phases, and in the slightly more than two years of the West Africa outbreak, some promising drugs managed to pass through all three phases of clinical trial testing. Now, with a new outbreak ongoing in the Democratic Republic of Congo, Bausch says some of the drugs tested during the earlier outbreak are showing promise in the new outbreak "and a new vaccine trial has started a few weeks ago."

New drugs knock out drug-resistant TB

TB is the world's biggest infectious disease killer, responsible for 1.5 million deaths in 2018, according to the World Health Organization. And in 2017, an estimated 558,000 people were diagnosed with a strain of TB that does not respond to traditional treatment. It's known as drug-resistant TB.

Early treatments for the drug-resistant disease required injections over many months, and the side effects, such as hearing loss, kidney failure, depression or psychosis, can be worse than the disease, says Dr. Wafaa El-Sadr , director of ICAP at Columbia University's Mailman School of Public Health. But in the past decade, two drugs, bedaquiline and delaminid, have emerged to treat drug-resistant TB. "They're taken by mouth and are well-tolerated," she says. As the simpler, safer treatments become available, she says, they could be game changers for patients in the developing world.

Digital media tracks diseases

In the 2010s, big data has been shown to have huge potential to save lives, says Dr. Ian Lipkin , director of the Center for Infection and Immunity at the Mailman School of Public Health at Columbia University. He talking about combining disease information from huge data sets, including Facebook, Twitter and digital news sites, through which researchers and health officials can spot outbreaks of disease, determine vulnerability of different populations and track the spread of disease.

"The earlier you detect an outbreak, the more likely it is that you can prevent its spread," he says.

Such automated systems already include HealthMap , Global Public Health Intelligence Network, and ProMED Mail. In 2014, for example, HealthMap used local news reports to provide an alert about a mysterious hemorrhagic fever in Congo more than a week before the World Health Organization announced the outbreak of Ebola there. Even a few days warning on a devastating outbreak could conceivably help health systems gear up to respond.

A vaccine deals a blow to meningitis A

In 2010, a vaccine called MenAfriVac was approved for use by the World Health Organization. By 2016 was available in all 26 countries of Africa's "meningitis belt," a group of 26 countries that suffer from a wave of meningitis A outbreaks about every five to 14 years. The disease causes protective membranes around the brain to swell, with symptoms of fever, headache and neck stiffness, according to the Center for Global Development's book, " Millions Saved ."

"You wake up in the morning normal, and you can be dead by afternoon," says Amanda Glassman, executive vice president of the Center for Global Development and co-author of the book.

Because of the vaccine, the disease has been reduced to the point that there are no epidemic-like outbreaks. Glassman estimates that MenAfriVac will prevent a million cases of meningitis in the next decade.

"The disease has been nipped in the bud as a public health threat," she says. Studies in Burkina Faso and Chad confirmed its effectiveness.

Root out corruption to root out worms

"In places where you have open defecation and kids playing in the dirt, you get kids with intestinal worms," says Glassman.

That exposure leads to malnutrition as the child's body competes with worms that feed on their blood and tissues. Studies have shown that children who have taken deworming pills are taller, healthier and stay in school longer, at a cost of pennies a year, says Glassman.

Until 2011, Kenya's Ministry of Education operated a successful deworming program that gave children a dose of inexpensive deworming pills — about 56 cents per pill paid for by global donors. The program came to a temporary halt after a corruption scandal rocked the Ministry and caused international donor organizations to withdraw funding from Kenya's education sector, according to Glassman.

But in 2012, a program called Deworm the World, with support from the World Bank, stepped in to provide fundraising and financial accountability. The program geared up again, and by 2014, more than 6.5 million Kenyan children received the pills. The effort reduced the incidence of intestinal worms by 83 percent.

Susan Brink is a freelance writer who covers health and medicine. She is the author of The Fourth Trimester and co-author of A Change of Heart.

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