Malaria menace

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The WHO believes the disease can be eradicated by 2030 with the right focus and funding. Anne Gulland traces the progress of the fight

Orlando Brooke was 18 and on a gap year in Africa when he was struck down by malaria. His symptoms appeared as he attempted to scale Kilimanjaro in Tanzania and, mistaking them for altitude sickness, he descended.

“I got on to a bus, but within an hour I was feeling so ill that I got off. I was in the middle of the African bush and I just crumbled by the side of the road. I had no strength. I felt awful – imagine the worst flu you’ve ever had and times it by 10,” he says. Fortunately he was picked up by a kindly local, Andrew, who took Brooke to hospital in the nearby town of Arusha.

“A doctor took my blood and then a few hours later came back and said ‘Mr Orlando Brooke, you have malaria’. I thought this was my death knell – I thought I was going to die,” says Brooke.

Like many travellers, Brooke had been taking doxycycline anti-malaria pills, but they are not 100 per cent effective. He thinks he got the disease on the bus journey to Kilimanjaro, where he had been “savaged” by mosquitoes during the night.

After a week of treatment, he felt stronger, but his weight had dropped to just 7st 7lb (48kg). He returned to his teaching job in Zambia and didn’t tell his family about his near-death experience until he returned home.

Fifteen years later, Brooke, now an actor in London, still raises money through sponsored runs for the charity Malaria No More.

As a relatively well-off westerner, Brooke knows he was lucky when he became ill. “I was able to pay for the drugs and the hospital treatment – a lot of local people can’t afford it,” he says.

A GLOBAL KILLER

Most of Africa is affected by the disease as are south-east Asia, Central and South America, the Dominican Republic and Haiti and parts of the Middle East.

In 2016, more than 1,600 people were treated for malaria in the UK and six died. Most of those, says Public Health England, did not follow advice on how to avoid the disease, such as taking anti-malarial drugs like mefloquine, doxycycline and chloroquine, covering up and using insect repellent.

Anti-malarial drugs can reduce the symptoms of the disease but, as Brooke and many other travellers have found to their cost, they are not a magic bullet. Often they are not straightforward; some of them have to be taken one or two weeks before arriving in a malaria-infected country and up to four weeks after leaving, tempting some less conscientious travellers to give them up before finishing the course.

Other drugs, famously mefloquine, also known as Lariam, can have some side-effects, such as anxiety and hallucinations, and people with a history of mental health problems are advised not to take it.

In 2016, the last year for which data are available, there were an estimated 216 million cases of malaria worldwide. Of those infected, a staggering 4,45,000 died – 1,219 lives lost every day or nearly one a minute.

After a big push to eradicate the disease in the Fifties and Sixties, it has surged back with a vengeance, gaining a particular stranglehold in Africa, which now accounts for 90 per cent of all cases. A second push over the past decade was initially successful, reducing the number of cases by about 20 per cent in just five years, but progress has stalled.

A new fightback is being planned. The World Health Organisation (WHO) believes we are at “crossroads” and advances in science mean it should be possible – with the right focus, funding and international co-operation – to eradicate the disease completely by 2030.

Malaria is a complex disease and to fight it, experts are waging war on three fronts: the malaria parasite, the mosquito that carries it and the human behaviours and living conditions that can cause it to spread.

Pedro Alonso, the director of the global malaria programme at the World Health Organisation, is in search of a “game-changer” – a vaccine, treatment or control technique that will finally eradicate the disease. Many global health experts are pinning their hopes on work being done by an international consortium of researchers, led by Imperial College London.

Only the female mosquito transmits malaria and researchers are using a gene-editing technique to interfere with the Anopheles gambiae mosquito – one of the major transmitters of malaria – so that it only carries male eggs. This is called gene drive, where a whole species is “persuaded” to adopt a gene. Researchers believe that after 20 generations – around two years – this modification will set in, and this genetically modified mosquito will eventually die out.

Delphine Thizy, the stakeholder engagement manager of the project, says: “It’s going to be another decade before this is ready to use.”

Other genetic tools include sequencing techniques. Researchers at the Wellcome Sanger Institute in Cambridge have mapped 4,500 genes of 500 malaria parasites to create the Malaria Cell Atlas: an online database freely available to researchers around the world to help them work out precisely which drugs and vaccines are effective and which aren’t.

VACCINES AND TREATMENTS

Vaccines have always been key. From this September, children in Kenya, Ghana and Malawi will get the first doses of the RTS,S vaccine, developed by the British pharmaceutical giant GlaxoSmithKline (GSK). While the launch of the vaccine is a landmark in the war against malaria, in trials it only reduced the number of deaths by 40 per cent. It also has to be given in four doses, with the fourth administered 18 months after the third.

A single-dose vaccine is the holy grail. Researchers are not there yet but there are promising treatments in development that could provide some long-term protection, as well as helping fight drug resistance: a prospect that is a real worry for malaria researchers and doctors.

At present, the main treatment for malaria is artemisinin-based combination therapy (ACT). In south-east Asia, where malaria is less widespread, malaria parasites have developed drug resistance, which has spread from south-east Asia to Africa. The development of new treatments is key in ensuring that researchers stay one step ahead of the parasite.

The development of new treatments means that there are now five combinations that can be used to treat malaria, giving doctors more choice if resistance becomes an issue. There are also new formulations for children that are easier to administer.

But there is still a long way to go. Alonso of WHO is clear that funding and political will are now both crucial to the fight.

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