The Economist - UK (2019-06-01)

54 TheEconomistJune 1st 2019

1

T

hese shouldbe hopeful days for those

battling malaria. Deaths from the dis-

ease have fallen to around 435,000 a year,

from perhaps five times that number a cen-

tury ago. On May 22nd the World Health Or-

ganisation (who) declared Algeria and Ar-

gentina malaria-free, bringing to 38 the

number of countries now officially rid of

the disease. Algeria will be regarded as a

particular success because it is in Africa.

The continent suffered 90% of an estimat-

ed 219m cases worldwide in 2017. But two

big clouds darken the outlook. One is the

stubborn persistence of malaria south of

the Sahara. The other is the emergence of

new strains of the disease resistant to the

available treatments.

Fewer Africans are dying from malaria

but the estimated number of cases has

barely changed since 2011. Ten African

countries and India account for 70% of glo-

bal cases. Numbers in India are falling, but

not in the worst-afflicted African coun-

tries. Some places, such as Zambia (see box

on next page), are trying hard to tackle the

disease. But malaria is proving resilient.

One reason may be the declining share of

families that use anti-mosquito sprays in

their homes. Another may be resistance to

the insecticides used in bed nets or sprays.

And, though about three-quarters of the

$3.1bn the world spends to fight the disease

each year goes to Africa, funding per per-

son has fallen in recent years in the most

malaria-prone countries. Perhaps most

important, these countries also have shod-

dy public-health systems, especially in war

zones such as northern Nigeria.

Such places are typically not equipped

to cope with new treatment-resistant

strains of the disease. More than 50 years

ago, variants resistant to chloroquine, a

past treatment, travelled around the world.

And South-East Asia, where those variants

appeared, is again suffering local out-

breaks incurable by some of the main de-

fences used against the disease, artemisi-

nin-based combination therapies (acts).

Work at Phuoc Long Hospital in Binh

Phuoc province in southern Vietnam,

which borders Cambodia, is thus of global

interest. The facility’s 250 beds serve

around 200,000 people. Funds are tight. As

officials hold a morning meeting under a

golden bust of Ho Chi Minh, Vietnam’s first

communist leader, a toothless former sol-

dier, still in uniform, pushes his bicycle

through a courtyard with peeling paint.

Doctors proudly show off new equipment

for researching malaria. One reckons the

hospital sees only 100-odd cases a year. But

the rate of failure for one conventional act

treatment is already frightening—above

60%, says Professor Hien Tran Tinh of the

Oxford University Clinical Research Unit.

Two types of malaria parasite most trouble

the Greater Mekong Region. Plasmodium

falciparumkills the most people globally.

Plasmodium vivaxis to blame for many of

the cases of malaria outside sub-Saharan

Africa. Less deadly than P. falciparum, it can

linger in the liver after recovery and trigger

a relapse. Its debilitating cycles leave vic-

tims susceptible to other diseases.

Like any living organism subject to suf-

ficient pressure, malaria parasites mutate

to survive. In parts of the Mekong, the para-

sites Anopheles mosquitoes inject into the

human bloodstream are resisting conven-

tional treatment. By 2030, the whohopes

to see malaria eliminated in the region be-

fore its resistant parasites spread.

Curbing malaria

Anopheles’ big adventure

PHUOC LONG

As malaria mutates to survive, its elimination is proving difficult

International

55 MalariainZambia

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