The War on Malaria

Humanity’s fight against our ancient foe just entered its third, and most critical phase.


He was an impenetrable darkness. I looked at him as you peer down at a man who is lying at the bottom of a precipice where the sun never shines … I was startled to hear him say a little tremulously, ‘I am lying here in the dark waiting for death’ … He cried in a whisper at some image, at some vision, — he cried out twice, a cry that was no more than a breath — “The horror! The horror!”
Joseph Conrad
Heart of Darkness (1899)
 
With tears and toiling breath,
I find thy cunning seeds,
O million-murdering death.
Sir Ronald Ross
Winner of the Nobel Prize for Medicine (1902)

Malaria is old. And it’s mean. Humans have been suffering at the hands of the plasmodium parasite for a long time. Historical reports of malaria symptoms appear in texts as far back as the ancient Egyptians and the Greeks, and at various times the disease has affected nearly every region of the world. Joseph Conrad was terrified of it, and Shakespeare called it the ague and used its “poisoned air” and “reek of rotten fens” (the smell of mosquito breeding grounds) as his favourite metaphor for all things wicked.

For good reason. Over the course of our species’ history, malaria has killed more people than all of humanity’s wars combined. It continues to be a far deadlier killer than human beings. Murders account for around 437,000 deaths annually, while malaria killed 445,000 people in 2016, nearly one life every minute. It killed twice as many people as Ebola during West Africa’s Ebola crisis, and is responsible for the majority of deaths in South Sudan and in those parts of Nigeria still battling Boko Haram. It is the disease most frequently dealt with by Médecins Sans Frontières medical teams, who treated 2.5 million people for it in 2017.

There are five types of malaria that can infect humans. Plasmodium falciparum, the most commonly found type in sub-Saharan Africa, is the most malicious. It causes half of all malaria cases and about 90% of deaths. Most of those are babies and young children. It’s an agonising way to go — shaking, sweats, fever, vomiting, splitting headaches, terrible pain, and eventually death, in as quick as 48 hours. Even if you survive, it can leave you permanently brain damaged. Here is one person’s description:

I awoke to what felt like lightning going through my legs, and then spreading through my body and in my head. Probably the worst headache, body aches, and chills you could possibly imagine. It felt like I was being stung repeatedly by an electric shock gun and could barely control my movements. The pain was so intense; I believed I was dying.
 A magnified drop of infected blood — the plasmodium parasite amongst red blood cells

A magnified drop of infected blood — the plasmodium parasite amongst red blood cells

Fighting this disease is a war that’s truly worth waging.

The first phase of that war took place in the 1950s and 1960s. At the time, malaria was endemic in many places, including southern Europe and the southern states of the United States. By the 1970s, much of the rich world had wiped it out. However once the global focus moved on, malaria returned with a vengeance, gaining a stranglehold on Africa. It was a silent disaster, flying under the radar for the wealthier half of the world’s population that no longer needed to worry about it.

That changed in 2000. The war on malaria entered its second phase, with the Abuja Heads of State Declaration and the launch of the Millennium Development Goals. Philanthropic and government spending increased 15 fold, and by 2015, one billion insecticide-treated mosquito nets had been given out in Africa alone. Cheaper drugs arrived on the market, and the introduction of rapid diagnostic tests made it possible to figure out whether someone was suffering from malarial or non-malarial fevers, making quicker treatment possible.

Progress was remarkable. 17 countries managed to eliminate malaria, and 21 came close. Several countries in the Middle East and central Asia were certified as malaria-free, including Morocco, Armenia and Turkmenistan. In 2017, Kyrgyzstan and Sri Lanka joined their ranks, having gone three years without recording an indigenous case. China used to have 24 million annual malaria cases in the early 1970s; last year, they announced that nobody was infected via mosquito bites, and are aiming to declare the country malaria free by 2020.

This second phase was the one that turned the tide. By ramping up funding, and concentrating it on one disease alone, the fatality count fell from 839,000 at the turn of the millenium to 446,000 in 2015. In the space of 15 years we managed to save 7 million people — mostly children — from truly awful deaths. It’s one of the most remarkable and under-celebrated public health achievements in our species’ history.

That phase is now over. Progress has stalled.

The World Health Organisation’s most recent annual malaria survey reported that in 2016, for the first time in a decade, there were 5 million more malaria cases than in the previous year. Progress has also stalled on on reducing mortality: 445,000 deaths in 2016, only a marginal decline from 2015.

Part of the problem is that funding seems to have plateaued. To beat malaria the world needs to be spending $5 billion to $6 billion annually, yet in 2016, only $2.7 billion was made available. 216 million people in 91 countries are still being infected every year. The same tools aren’t as effective and resources don’t stretch as far. Mosquito nets soaked in insecticide are the primary form of protection, but despite incredible progress, more than half of households in sub-Saharan Africa don’t have them yet. Mosquitoes have also been evolving the ability to resist the pyrethroid insecticides most commonly used on the nets, and the trait is spreading, putting millions of lives at risk.

Malaria is fighting back, and the world is now at a crossroads.

The war is now entering its third, and most crucial phase. A response is starting to form. The new plan of attack is multi-pronged, and even more reliant on science and technology. At stake are nearly half a million lives a year.

A new generation of mosquito nets impregnated with a new kind of insecticide, chlorfenapyr, have just been given the go ahead by the WHO — its first recommendation for a product based on a new insecticide class in more than 30 years. Another kind of net, incorporating a chemical called piperonyl butoxide, was trialled in a two-year study for 15,000 children in Tanzania, and reduced the prevalence of malaria by 44% compared with a net treated only with pyrethroid.

A malaria vaccine is also in the works, after decades of development, and is currently being rolled out in Kenya, Ghana and Malawi. New genetic sequencing techniques are allowing data to be gathered in the field and transmitted swiftly to sophisticated surveillance systems, allowing scientists to identify evolving strains of malaria parasites and track drug and pesticide resistance.

In the tiny African kingdom of Swaziland, one of the most effective tools is a telephone number: 977. When someone tests positive at a clinic, a nurse immediately dials the number to report the case to the country’s national emergency response center. The call triggers a text message to the national malaria program team, which dispatches investigators, armed with computer tablets, satellite maps and GPS, to interview the patient and test all people living within a kilometer radius of their home. A separate team is called in to reapply insecticide to the walls of homes in the community to help protect other families from infection.
 
Genetic sequencing and genetic editing technologies are also creating new approaches to combating the disease. Chinese researchers, for example, have been able to sequence the genome of Artemisia annua, a Chinese shrub producing a potent antimalarial compound artemisinina, revealing new ways to extract more anti-malarial medicine from the plant. And earlier this year, a collaboration between British and US researchers revealed the core genes that are essential for the deadliest malaria parasite to survive, revealing new targets for drugs or vaccines.

Gene editing techniques are giving scientists the ability to create gene drive technologies that change a mosquito’s DNA. In the ones that transmit malaria, genetic changes can be used to cause infertility or permanently change the insects’ ability to carry and pass on the parasite. These approaches are controversial; people are understandably concerned about ‘tinkering’ with nature. However, as Bill Gates recently pointed out when asked about the controversy, “Malaria itself is quite controversial — it kills about 400,000 kids a year.”

Ultimately, the next phase of fight against malaria will take many years and a range of new and old tools, from bednets and mosquito traps to a new vaccine and next generation gene tools. And none of it will happen without funding. Fortunately there’s signs of hope there too. Less than a month ago, at the 2018 Malaria Summit in London, 14 heads of state and leaders from science, business, and the aid sector committed $4.1 billion toward research, malaria treatments, prevention methods, and transmission surveillance.

This story, of the war on malaria, is one of the most epic things humans are engaged in right now. There are thousands of people racing against time in labs all over the world, and hundreds of thousands of volunteers, doctors and nurses on the frontlines, working every day to fight back against our ancient killer. Their efforts have already achieved the greatest public health success story of this millennium, but the work is far from finished. Billions remain at risk. It’s a fight worth having. Humanity may be on the brink of wiping out one of its oldest and deadliest foes — but only if we start paying a lot more attention.