Vaccine Initiative, a nonprofit dedicated
to malaria prevention and eradication.
With no viable alternative to arte-
misinin, increasing numbers of malaria
infections with delayed clearance follow-
ing artemisinin treatment are concerning,
experts say—and if resistance develops in
Africa, the results could be disastrous.
Strains with partial artemisinin resistance
have drawn a great deal of attention, even
being dubbed “super malaria” by some
media outlets. “I really caution us against
complacency,” says Kaslow. “I don’t think
there’s evidence today to say that resis-
tance is going to explode in Africa. But
tomorrow, it could. I would not put any-
thing past this parasite.”
Some scientists are less concerned
over the danger of ACT resistance, argu-
ing that the threat is overblown. Cur-
rently, the ACT arsenal remains strong
enough to defeat the parasite, says San-
jeev Krishna, a molecular parasitologist at
St. George’s University of London. “If you
have the right combination partner, then
your treatment is curative.”
Steve Meshnick, a professor of epide-
miology at the University of North Car-
olina at Chapel Hill, agrees that partial
artemisinin resistance is, for now, a mere
blip in the fight against malaria. “I’m not
saying it’s not a problem,” he says, “but I
think it gets too much attention.”A history of resistance
Resistance against malaria drugs has been
a battle since day one. Soon after chloro-
quine’s international release in the late
1940s, parasites began to fight back, par-
ticularly in Colombia, Thailand, and Cam-
bodia,^2 which were subjected to mass chlo-
roquine treatments, often at low doses
that promoted the evolution of resistant
parasites. The drug was even added to
table salt in some countries in a desperate
attempt to curb infections.^3
Sure enough,P. falciparum strains in
these areas developed multiple mutations
in the transmembrane protein PfCRT.^4 This
allowed the parasite to reduce the accumu-
lation of the drug in its digestive vacuole,
where it normally kills the parasite by bind-
ing to subunits of oxidized heme, thereby194519501955196019651970197519801985199019952000200520102015THE RISE OF MALARIA DRUG RESISTANCE
Plasmodium falciparum resistance to artemisinin-based combination therapies ( A C Ts )
started to crop up around 2007. Infections, especially in the Greater Mekong area of
Southeast Asia, seemingly survived treatment. This was largely due to the pairing of
artemisinin derivatives with older drugs that had existing resistance problems. But some
experts think the emergence of partial resistance to artemisinin itself—which allows
parasites to persist for longer in the body following treatment—could also play a role.
195019801980198020001980198019801980Thai-Cambodian border
(and later on the Colombia-
Venezuela border)ThailandChinaVietnamThai-Myanmar borderThai-Cambodian borderWestern CambodiaWestern CambodiaThailandChinaChloroquineDate of widespread
releaseDate of fi rst
resistanceOrigin of resistanceArtemisinin-combination
therapiesSulfadoxine-
pyrimethaminePyronaridine
monotherapyArtemisinin
monotherapyMefloquine
monotherapy
Piperaquine
monotherapyArtesunate-
mefloquineArtemether-
lumefantrineDihydroartemisinin-
piperaquinePyronaridine-
artesunate