|
The
Prevention and
Treatment of Malaria
|
Malaria
is a preventable infection that
can be fatal if left untreated.
You
cannot be vaccinated against
malaria, but you can protect
yourself
|
Avoidance
of Bites
Mosquitoes
cause much inconvenience because
of local reactions to the bites themselves
and from the infections they transmit.
Mosquito bites spread other diseases
such as yellow fever, dengue fever
and Japanese B encephalitis.
 Mosquitoes
bite at
any time of day but the anopheles
bites in the night with most activity
at dawn and dusk. If you are out
at night wear long-sleeved clothing
and long trousers.
Mosquitoes
may bite through thin clothing,
so spray an insecticide or repellent
on them. Insect repellents should
also be used on exposed skin.
Spraying insecticides in the room,
burning pyrethroid coils and heating
insecticide impregnated tablets all
help to control mosquitoes. If you
are sleeping in an unscreened room
a mosquito net (which should be impregnated
with insecticide) is a sensible precaution.
If sleeping out of doors it is essential.
Portable, lightweight nets are available.
NOTE: Things like Garlic, Vitamin
B and ultrasound devices do not prevent
mosquito bites.
Taking
Anti-Malaria Tablets
 It
should be noted
that no prophylactic regimen is
100% effective and advice on malaria
prophylaxis changes frequently.
There are currently five prophylactic
regimens used (A,B,C,D & E),
due to the differing resistance
that exists by the malaria parasites
to the various drugs used. (See
the above map of Malaria Endemic
Areas).
The
tablets you require depend on
the country to which you are travelling
(see the table page). Start taking
the tablets before travel take them
absolutely regularly during your stay,
preferably with or after a meal and
continue to take them after you have
returned. This is extremely important
to cover the incubation period of
the disease.
Prompt
Treatment
If
you develop a fever between one
week after first exposure and up to
two years after your return, you should
seek medical attention and inform
the doctor that you have been in a
malarious area.
 Anyone
with suspected malaria should
be treated under medical supervision
as soon as possible. If malaria
is diagnosed then treatment is a
matter of urgency. Treatment should
not normally be carried out by unqualified
persons.
The drug treatment of malaria
depends on the type and severity of
the attack. Typically, Quinine Sulphate
tablets are used and the normal adult
dosage is 600mg every twelve hours
which can also be given by intravenous
infusion if the illness is severe.
Remember: Prevention is better
than cure and over two million people
die from malaria every year. It is
a very serious illness!
 Side
Effects of Anti-Malarials
Like
all medicines,
anti-malarials can sometimes cause
side-effects:
Proguanil
(Paludrine) can cause nausea and simple
mouth ulcers.
Chloroquine
(Nivaquine or Avloclor) can cause
nausea, temporary blurred vision and
rashes.
Patients
with a history of psychiatric
disturbances (including depression)
should not take mefloquine as it may
precipitate these conditions. It is
now advised that mefloquine be started
two and a half weeks before travel.
 Doxycycline
does carry some risk of photosensitisation
i.e. can make you prone to sunburn.
Malarone
is a relatively new treatment and
is virtually free of side effects.
It is licensed for use in stays of
up to 28 days but there is now experience
of it being taken safely for up to
three months.
No
other tablets are required with
mefloquine or doxycycline or Malarone.
 Drug
Resistance
It is the plasmodia that cause malaria
that develop resistance to anti-malarial
drugs not the mosquitoes that transmit
the disease.
Resistance to antimalarial drugs is
proving to be a challenging problem
in malaria control in most parts of
the world. Since the early 60s the
sensitivity of the parasites to chloroquine,
the best and most widely used drug
for treating malaria, has been on
the decline.
Drug resistance is the ability of
a parasite species to survive and
multiply despite the administration
of a drug in doses equal to or higher
than those usually recommended but
within the limit of tolerance.
 Newer
antimalarials have been developed
in an effort to tackle this problem,
but all these drugs are either expensive
or have undesirable side effects.
The discovery of chloroquine revolutionalised
the treatment of malaria, pushing
quinine to the sidelines.
However, after a variable length of
time, the parasites, especially the
falciparum species, have started showing
resistance to these new drugs.
Resistance is most commonly seen in
P. falciparum whereas only sporadic
cases of resistance have been reported
in P. vivax malaria.
Resistance to chloroquine is most
prevalent, while resistance to most
other antimalarials has also been
reported.
Resistance to chloroquine began from
two epi-centres; Columbia (South America)
and Thailand (South East Asia) in
the early 1960s. Since then, resistance
has been spreading world wide.
Recently, cases of mefloquine resistance
have been reported from areas of Thailand
bordering with Burma and Cambodia
(see map above). Travellers to Thailand
are therefore advised to avoid using
mefloquine when travelling to these
risk areas.
 Because
mefloquine is structurally similar
to chloroquine, cross resistance
is possible due to the prolonged
half life of mefloquine. 
|
