Some of the world's big challenges get a lot of attention. Climate change, wars and immigration are constantly in the news, and receive large funding from states and individual philanthropists. Other significant problems such as tuberculosis and malnutrition receive less airtime and people are less aware about them, but they count among major global priorities, with allocated funding.

Even the aptly named Neglected Tropical Diseases like rabies, river blindness and leprosy, which claim about 200,000 lives each year in less — and least-developed countries, have their own programs in the World Health Organization.

But there is a challenge which we hear little to nothing about, but which affects more than 1 billion people across the world and could be addressed very efficiently. We could reasonably call it the "Neglected Enormous Disease".

The world has made significant inroads into tackling infectious diseases. Two centuries ago, they routinely caused almost half of all deaths, but today they kill less than 15 percent. Instead, half of all deaths are caused by the two biggest killers, cardiovascular diseases and cancer. Cancer causes about 18 percent of all deaths, but it is hard and costly to tackle with only modest success rates.

The biggest killer of all, which is technically called a cardiovascular disease but mostly consists of heart attacks and strokes, accounts for more than 18 million deaths each year, making up one-third of all global deaths. A big part of the problem is unhealthy diets, physical inactivity, and tobacco and alcohol consumption, which cause obesity and high blood pressure.

While doctors will tell you to stop smoking, cut down on alcohol and salt, exercise more, and consume fewer calories but more fruits and vegetables, this advice is evidently fairly difficult to follow. Tobacco and alcohol regulation can make this easier, along with reducing the levels of salt in ready-made meals.

But focusing on high blood pressure is key to curbing this "Neglected Enormous Disease". Incredibly, the indicator of high blood pressure is the single biggest global death risk, leading to almost 11 million deaths annually, accounting for 19 percent of all fatalities in the world.

As the world's population is aging, more and more people are living with high blood pressure — the number of people affected has doubled in the past 30 years to about 1.3 billion. Because there are no obvious symptoms, almost half don't even know it, and four out of five are not adequately treated.

This combination makes high blood pressure both enormously impactful and surprisingly neglected. The good news is that treating high blood pressure is incredibly cheap and effective with one or more pills that are off-patent and cost next-to-nothing. This is done fairly well in rich countries, but we should be doing this across the whole world.

Community screenings for high blood pressure cost as little as $1 per person, and the prescription of blood pressure medications often costs only $3-11 per year. Peer-reviewed research shows that controlling high blood pressure in less — and least-developed countries would cost about $3.5 billion annually. But it would save almost a million lives every year. Put into economic terms, each dollar spent would achieve $16 in returns to society, making it one of the world's most efficient policies.

Despite becoming a bigger killer than infectious diseases even in the developing world, chronic diseases such as cardiovascular diseases receive very little funding. External funding accounts for almost 30 percent of health spending in low-income countries, but only 5 percent of all this funding goes toward the treatment of chronic diseases. For instance, in Nigeria, where heart disease is now responsible for one in every 10 deaths, the Federal Ministry of Health's Non-communicable Disease Division has launched a new program to control high blood pressure. This is an excellent start — but it is important that donors step up their support for programs that increase access to affordable, comprehensive high-quality prevention and treatment services for high blood pressure not only across Africa but in all developing nations.

High blood pressure is the leading global killer risk, yet it receives little attention and even less funding. For just $3.5 billion a year, we can implement one of the best solutions for the world, saving millions of lives.

We just need to know.

The author is president of the Copenhagen Consensus and a visiting fellow at Stanford University's Hoover Institution. The views don't necessarily reflect those of China Daily.

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