Malaria
Introduction
Malaria is the most common really serious tropical disease, and apart from road crashes is the
most likely thing to bring you home in a body bag or cause you serious illness. It is found in over
97 countries and 125 million international travellers each year visit these countries and are at
risk of catching it. Malaria comes in 5 ‘models’, the most feared being falciparum malaria.
It specialises in people who have no resistance (i.e. those who were not brought up in a
malarious area). It also goes for those who don’t take their malaria prevention tablets or who
don’t try to prevent the Anopheles mosquito from biting them. This puts a lot of adventure
travellers, volunteers, aid workers and mission partners at high risk. It also means those living in
a non-malarious country and visiting friends and relatives in affected countries are very
vulnerable.
Female Anopheles mosquitoes inject you with a red cell-busting Plasmodium parasite mainly
during twilight hours (it can be any time from about an hour before sunset through to an hour
after dawn). The parasites multiply in your liver before breaking out into your blood stream, at
which time they cause the illness. The time between the fateful bite and developing the illness,
the incubation period, is 7 days or longer.
What are the symptoms?
Tell-tale signs are similar to severe flu: fever, sweating and shivering, headache, nausea and
vomiting, diarrhoea, aching muscle and joints, backache. Malaria can come on very rapidly,
especially cerebral malaria- a severe form of falciparum malaria almost always found in those
who are not taking their malaria prevention tablets. This can lead to coma, convulsions and
death. However malaria sometimes causes much milder symptoms, which can mimic other
diseases, so have a high degree of suspicion.
How can I prevent malaria?
Get expert travel advice well before leaving i.e. several weeks before. You must get customised
advice about your particular trip. How you tackle malaria will depend on your medical history,
what medications you are currently taking, where you are going, what you will be doing, what
time of year you will be travelling, and how long you will be staying in a malarious area. It’s
only when your adviser has the full picture that you can get the best advice.
There are 4 key action points:
·
Avoid getting bitten - this means using effective insect repellents (ideally those containing
DEET at a concentration of 50%, safe to use in adults and children over 2 months) and
wearing appropriate clothing to cover the parts mosquitoes find most tasty – mainly lower
legs and feet, arms and wrists, but any part of your skin can be bitten. Sleep under a
mosquito net which has been ‘impregnated’ with in an insecticide such as Permethrin, or
an equivalent. For more information, click here
·
Take malaria prevention tablets - if this is what your travel health advisor recommends.
This does not just mean taking them for the first week or two and then stopping because
you get trivial side-effects, your friends aren’t bothering or local friends say it’s a waste of
time. If you are getting troublesome side-effects change to another antimalarial, rather
than just stopping.
·
Treat any symptoms without delay - if you think you have malaria see the best doctor
available as soon as possible, ideally within 8 hours and certainly within 12 hours of your
symptoms starting. Get a malaria blood slide test (which usually only involves a fingerprick). You should make sure the advice and treatment recommended agrees with the
expert information you have received before travelling, as many health care professionals
in developing countries may not have the best treatment available or may be using less
effective preparations. If you have an emergency standby malaria treatment kit you should
take this with you, and suggest this is used if the correct treatment is not available. If your
malaria blood test is negative and your symptoms continue or “are suspicious” you should
self-treat anyway, but remain under the care of a doctor. A negative blood slide does not
necessarily mean you don’t have malaria. It could be that no ‘blood forms’ were present at
the time of the test, or the lab technician was having an off-day.
·
Consider taking an emergency standby treatment kit - this is essential if you will be more
than 8 to 12 hours from good health facilities (either when working or on holiday) in a
country where malaria is common and effective treatment hard to obtain. Standby
treatment is especially useful in sub-Saharan Africa. There are two reasons why you use it:
either because you are remote from good medical care and you have symptoms of malaria
or because effective drugs for treatment are not available at the clinic you go to.
Pregnancy
It has been scientifically proven that Anopheles mosquitoes are attracted to pregnant women.
This puts both mum and baby at real risk. If you are pregnant or considering becoming pregnant
in a malarious area get specialist advice, which will often mean avoiding living in seriously
affected areas. If you really must live or travel in a malarious location while pregnant take
extreme care to avoid getting bitten, take the malaria prevention tablets recommended by your
health advisor and report any symptoms at once.
Children
Malaria can be very serious in the younger generation, and preventing bites, though vital, can be
more difficult. This makes taking the correct malaria prevention tablets all the more important.
Coming Home
Danger time! Malaria often strikes when you are relaxing in the first few weeks after leaving a
malarious area. Falciparum malaria can do this for up to 3 months, other forms of malaria for a
year or longer. Continue taking your tablets for the full length of time recommended and
immediately report any suspicious symptoms at your nearest Accident and Emergency
Department even if it’s night time or the weekend. You can also contact InterHealth if you are
in the London area.
Further tips to avoid getting malaria
·
Screen your house (windows, doors, etc) and make sure mozzies can’t get through the
holes.
·
Use mosquito coils or an electric mosquito killer during the evening.
·
Use aerosol bug-killer sprays in the house late afternoon e.g. in bathroom and bedroom.
·
Turn on the air-conditioning, or sleep under a fan.
·
Wear light coloured clothing, especially in the evening and spray it with Bug Proof, a
Permethrin-based insecticide for use on clothes.
·
Get rid of nearby breeding sites – any stagnant water, which also helps to prevent dengue
fever.
·
Watch your work-life balance and avoid getting over-tired as this makes malaria more
likely.
Further Guidance and Information
More information can be found in: The Traveller’s Good Health Guide’, Ted Lankester; 3rd
Edition 2006
InterHealth Worldwide Authors
Emley Pine
Last reviewed: February 2015
Copyright © InterHealth
While InterHealth endeavours to ensure that the information published in this guidance note is correct, InterHealth does
not warrant the accuracy and completeness of the material in this guidance note. The information in this guidance note
is for information only and should not be used for self diagnosis or self treatment. Readers are always encouraged to
seek medical help from a doctor or other competent professional health adviser.