Paul Farmer is the Kolokotrones University professor at Harvard University, an infectious disease physician at the Brigham and Women’s Hospital and co-founder of the nonprofit Partners In Health.

Port Loko is not far from Freetown , the capital of Sierra Leone and a global hub of maritime commerce. City and town, linked by paved roads, remain epicenters of Ebola transmission and deaths. Getting to zero new infections is the overarching goal of what is now the world’s largest public-health undertaking. But it’s still far from an ambitious clinical endeavor. The numbers say it all. Not a single American has died of Ebola; the majority of Europeans infected have survived; a Cuban survivor is already back here at work. Across West Africa, 70 percent of those afflicted die. And that figure applies only to the sick who receive care at treatment centers: More than 90 percent of those who stay home perish.

A year into the epidemic, with billions of dollars pledged to fight Ebola, what accounts for the extreme variation in death rates? How can an ambitious public-health effort be so unambitious clinically? There are many reasons for variations in survival, but among the top five are not that shipped-home expatriates received experimental treatments. What kills most Ebola patients is a massive loss of the body’s vital fluids — up to 10 liters of day — along with proteins and electrolytes, primarily through vomiting and diarrhea. And that’s not counting fluid losses from fever in broiling treatment centers, whose makeshift appearance offers a clue to the quality of care within. Clinicians and other staff in the hot zone can barely stand more than a couple of hours inside the centers, their protective gear sloshing with sweat, rubber boots brimming with a foul mix of perspiration and chlorine.

We often hear there’s no treatment for Ebola or other hemorrhagic viruses. That’s not true. What the expatriate survivors all received was excellent supportive care, most of it from nurses. In medical parlance, the term “supportive care” does not mean hand-holding but the replacement of fluids and electrolytes; treatment of secondary infections (bacteria escaping from the gut, say, or malaria); and, in some cases, renal dialysis and assisted ventilation. All of this is standard practice in countries pleased to be able to call themselves “donor nations.”

Parents from these nations know how difficult it is to get a sick toddler to take in Pedialyte; vomiting kids can’t keep it down even when it’s made to taste like fruit drinks. Here in West Africa, we need swift and better intravenous access and intraosseous needles, which can infuse large volumes of fluid when patients arrive at clinics so dehydrated that it’s difficult to find a vein. Three weeks ago, a baby named Jariatu was found by a burial team, barely alive, in a house full of dead family members. She was taken to Port Loko, where nurses and doctors were unable to locate a vein for an IV; the baby was dying, too unresponsive to drink. So the Partners in Health team, Sierra Leoneans among them, did what they would do in Boston or Haiti: They inserted an infusion needle into the bone marrow of her tibia. It was three days before Jariatu was conscious enough to show any interest in taking anything by mouth. She’s expected to survive.

What we need — what we’ve always needed — to improve survival in West Africa is the capacity to safely deliver excellent supportive care. So what’s the debate about? It’s hard to deliver supportive care here, due to the obvious lack of staff and stuff and space, and it’s dangerous. Though they’re afraid of Ebola, as any sane person should be, thousands of medical professionals, most of them African, show up for work every day (a lack of electricity makes it hard to make a similar claim about night shifts, which is another cause of high mortality). Doctors Without Borders deserves special praise, since it was the first to sound the alarm and has brought thousands of volunteers and staff into the battle. When I noted to the New York Times recently that Doctors Without Borders wasn’t “doing enough,” what I meant was that we all need to provide better supportive care to increase survival. Double standards between such settings as Atlanta and Freetown are also harming efforts to find all patients with Ebola, which hampers efforts to isolate them from uninfected family members. Could there be a relationship between poor-quality care and people’s reluctance to seek it in hot and raggedy Ebola units, where patients are interned until death or until blood tests show no circulating virus?

The primary task of the doctors, nurses and others working in treatment centers is to unlink these two events, infection and death. The quality of care in this part of West Africa — not simply for Ebola but for more common ailments and injuries — must be improved. Improving care means introducing capacity to monitor electrolytes, which we’ve recently done in rural Sierra Leone, instead of doing a single lab test for Ebola. It means cooler units — even fans would help — and personal protective gear made for tropical conditions. It means improved nutrition and a lot more support for the public health delivery system.

Since hospitals with poor infection control have always amplified Ebola’s spread, the two tasks — stopping transmission and improving care — are the means by which the world’s largest outbreak will be halted and proper health systems built. Since the most shockingly inadequate part of the response has been clinical, the Partners in Health team recently signed what we jokingly called the Port Loko Accords: a pledge to drop case-fatality rates to less than 10 percent. We were extremely serious about the number, which is still higher than that in the affluent world. If we try and fail, we’ll keep trying while awaiting new and better ways to treat Ebola and other pathogens far more deadly for some — those bereft of decent health systems — than for others.