Drug-Resistant Malaria - libdoc.who.int - World Health Organization

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Radical therapy of microscopically diagnosed cases. It is
self-evident that a patient suffering from symptomatic malaria
should be radically treated, be the illness of an acute nature or
simply manifested by relatively minor clinical symptoms.
The question arises as to whether in holoendemic areas, semi-.
immune asymptomatic parasite carriers should be given treatment.
The question is part icularly pert inent in areas holoendemic
for malaria where a major portion of the population may be
asymptomatic carriers. With the exception of those individuals
who fall under the heading of high risk or special groups as
referred to in the previous section, the answer, in the absence of
intensive parallel control measures (e.g. effective vector
control), is probably not to treat them unless they develop
symptoms attributable to their parasitaemia.
(b)
Use of drug combinations
There is abundant evidence that the use of appropriate
combinations of drugs can at least delay the rate at which microorganisms,
including malaria parasites, become resistant to them,
as compared to the components when used alone. Combinat ions can
be of several types:
Complementary
Additive
acting on different stages of the parasites, e.g.
chloroquine plus primaquine in the treatment of
vivax malaria or in the prevention of transmission
of malaria by the gametocytoc idal act ion of
primaquine.
acting on the same stages, e.g. sequential qUlnlne
and tetracyc line in the therapy of multipleresistant
P.falciparum infection.
acting on the same stages, e.g. chloroquine plus
pyrimethamine us.ed prophylactic ally to prevent
resistance from developing in the asexual stages
(apart from a complementary, sporontocidal effect
of the pyrimethamine)
Potentiating
sulfonamides or sulfones with pyrimethamine. The
potentiating mixture retaining its activity against
all stages of the cycle which are fundamentally
susceptible.