The saying 'prevention is better than cure' holds very true when it comes to malaria and there are several options available. Risks vary depending on which part of the world you are travelling to. Highest risk areas at the moment are West African countries such as Gambia.
WHO and UNICEF released the Africa Malaria Report 2003, on April 25, which stresses that the death toll from malaria is still "outrageously high", killing more 3000 children in Africa every day, and that effective antimalarial drugs and insecticide-treated bed nets are not widely available to those who need them."Millions of people continue to suffer and die unnecessarily with 90% of malaria deaths occurring in Africa alone",
Other high risk areas include Papua New Guinea, the Soloman islands, the Thai/Cambodia and Thai/Myanmar (Burma) borders in Asia and the Amazon area in South America.
Chloroquine
Well tolerated but of limited use on its own because of
widespread resistance, but it can be used in areas such as
Central America where malaria is still sensitive. Safe,
minor side-effects can include GI upset and exacerbation of
psoriasis. It can be taken in pregnancy but must be used
with caution in the epileptic. Long-term use is linked to
retinal damage but this tends to be with the much higher
doses used in rheumatoid arthritis.
 | Chloroquine and proguanil Chloroquine 300mg (as base, two tablets) weekly plus proguanil 200mg (two tablets) daily is a safe, well tolerated and efficacious regime but needs strict compliance. Satisfactory for the pregnant traveller who insists on visiting a malarious area. Proguanil is rapidly absorbed, converted to cycloguanil (the active drug) in the liver and has a short half life of six to eight hours. Good levels of protection can be achieved if used correctly but side-effects include mouth ulcers and GI disturbance. If administered in pregnancy, folate supplements are advised. It should be used with caution in renal or hepatic insufficiency. It was recommended much more extensively in the past in multidrug-resistant areas where mefloquine is currently the drug of choice. However, the chloroquine/proguanil combination is good for the patient in whom mefloquine is contraindicated. For long term travel Proguanil and Chloroquine may be taken for periods exceeding 5 years.
Mefloquine | Mefloquine has been available in the UK since 1990 and has been prescribed prophylactically to an estimated 10m travellers worldwide. It is the preferred drug for multidrug-resistant malaria in sub-Saharan Africa. Experience with mefloquine is growing all the time and recommendations for its use are more widespread, particularly for longer durations of up to 3 years. This drug has been the subject of recent adverse media publicity in relation to its side-effects. This is unfortunate and may have something to do with the recent increases in reported cases of malaria. Serious side-effects include temporarily disabling neuropsychiatric disturbance affecting 1 in 140 travellers and convulsions which have been reported in one in 10,000 users. That said, the risk of these side effects need to be weighed against the risk of contracting malaria. Anyone starting treatment with Mefloquine should do so at least two-and-a-half weeks before they travel. They can then swap to another regime if its not suitable for them. Less serious side-effects include nausea, vomiting, dizziness, rash and sleep-disturbance. Mefloquine should not be given to anyone with a history of psychiatric illness or epilepsy or to women in the first trimester of pregnancy. Women should be advised to avoid pregnancy for at least three months after the last dose. It should also be avoided in severe hepatic or renal impairment. This drug is highly effective and is taken as a single 250mg tablet weekly which aids compliance. Resistance to mefloquine is unfortunately growing in some regions of South East Asia.
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| Maloprim No longer a first line agent because of side effects such as severe bone marrow depression and other toxic effects Contains pyrimethamine 12.5mg and dapsone 100mg. It is not used very often now in the UK for prophylaxis but can be useful in areas where falciparum-resistant strains occur, such as Australia and New Zealand. It is usually taken once weekly in combination with chloroquine.
Doxycycline | A tetracycline antibiotic, it is taken prophylactically as a 100mg daily dose but its use in the UK is limited. It is used more widely in Oceania for areas of multi-resistant falciparum malaria, but is worth considering for mefloquine-resistant areas in SE Asia, such as the Thai/Cambodian and Thai/ Myanmarian border areas. Side-effects include diarrhoea, rash and photosensitivity ( use sun block ,cover up, keep in shade). It should not be used for pregnant women or children. For long term use it can be taken for up to 2 years. |
| Malarone -Atovaquone/proguanil |
The dose is one tablet daily taken 1 to 2 days before travel, throughout stay
and for 7 days after return. It is currently licensed for periods of stay not
exceeding 28 days but there is now experience of it being taken safely for up to
3 months. Avoid in pregnancy. Not to be used in breastfeeding mothers.
Chloroquine was introduced in 1934 and for many years was the most valuable prophylactic agent available. The WHO had hoped chloroquine would play an important strategic role in its malaria eradication programme but this was not to be.
Chloroquine-resistant plasmodium falciparum first appeared in SE Asia in 1978 and since then has swept across the world.
Unfortunately, resistance to other drugs is beginning to follow the same pattern.
In SE Asia, multiple drug resistance (chloroquine, paludrine, Fansidar, mefloquine) is common and reduced sensitivity to quinine is reported in Thailand, Myanmar, Cambodia and Vietnam. In some parts of Thailand, treatment failure rates with mefloquine are as high as 50 per cent. Resistance to halofantrine appears to be following the path of mefloquine. New research includes:
| Artemesia derived from the Chinese herb Qinghaosu.
Chinese troops in Cambodia use the drug for prophylaxis
and it has been in use in China for over 20 years but
this has largely been ignored by the West.Artemesinins
are rapidly acting, highly effective, and well tolerated
with no resistance been reported to date.
A recent agreement between the World Health Organisation and Bayer should mean a new drug based on the active ingredient artemisone should be available by 2005 http://www.news.bayer.com/News/News.nsf/id/2002-0154 WHO currently recommends combination treatment with two antimalarial drugs that have different targets within the malaria parasite, one of which should be an artemisinin derivative.Several African countries have already changed their drug protocols--or are in the process of changing them--to include more effective treatments. For instance, KwaZulu province in South Africa has successfully changed to artemisinin-based combination therapy as first-line treatment, and Burundi, Zambia, and Zanzibar in Tanzania are preparing to implement the switch. However, lack of money and international help has forced some countries to switch to another monotherapy, or to less expensive non-artemisinin combinations.
Azithromycin is being investigated for prophylactic
use
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Spf66 is a synthetic copolymer vaccine developed in
Columbia by joining plasmodium merozoite
proteins. | |
Malaria is a medical emergency that requires urgent hospital treatment. Drug resistance to modern synthetic drugs, such as chloroquine, is such a problem that the tried and tested original quinine is used to treat falciparum malaria. However, both mefloquine and halofantrine are also used.A new drug Riamet( artemether and lumefantrine) is a useful treatment option for areas of multi-drug resistance. The course for an adult consists of six doses of four tablets over 60 hours. It has a cure rate in excess of 95 per cent.
Shock, renal failure and other complications of malaria may necessitate intensive therapy nursing in some situations.
Some travellers may be visiting remote parts where prompt medical attention is impossible. They can be provided with drugs for self administration. Suggested regimes are:
1 Quinine 600mg three times daily for a period of three days followed by three tablets of fansidar (pyrimethamine plus sulfadoxine).
2 Mefloquine as a single dose of 1,000mg or 15mg/kg, whichever is lower, if not used as a prophylactic. If standby treatment is being prescribed, it is important that a patient is properly advised on signs and symptoms of malaria and how to use the drugs appropriately; there is good evidence that most patients who take their standby treatment turn out not to have malaria.
Unfortunately the newer drug Riamet is probably not suited to self treatment due to its potential for causing cardiac problems and its interaction with a number of drugs including other antimalarials
Standby treatment is not a substitute for seeking urgent medical attention.
