Malaria is the most dangerous disease in Africa, and the greatest risk to the traveller. It is common throughout Zambia, and so it is essential that you take all possible precautions against it.
Prophylaxis regimes aim to infuse your bloodstream with drugs that inhibit and kill the malaria parasites which are injected into you by a biting mosquito. This is why you must start to take the drugs before you arrive in a malarial area – so that they are established in your bloodstream from day one. Unfortunately, the malaria parasites continually adapt to the drugs used to combat them, so the recommended regimes must adapt and change in order to remain effective. None is 100% effective, and all require time to kill the parasites – so keeping up the prophylaxis regime for the recommended time after you leave the infected area is usually paramount.
It is vital that you seek current advice on the best antimalarials to take. If mefloquine (Lariam) is suggested, start this two weeks before departure to check that it suits you; stop it immediately if it seems to cause vivid and unpleasant dreams, mood swings or other changes in the way you feel. Anyone who is pregnant, has been treated for psychiatric problems, is epileptic, has suffered fits in the past, or has a close blood relative who is epileptic should avoid mefloquine. If Lariam is not suitable then either Malarone or doxycycline may be suggested. Malarone (a daily tablet) is as effective as Lariam, but has the advantage of fewer side effects and may be used in epilepsy. It only needs to be started two days before entering a malaria area and is continued for just seven days after leaving. It is currently licensed in the UK to use for three months and there are also weight-based paediatric tablets for children under 40kg. The down side is that Malarone is very expensive, so tends to be favoured for shorter trips.
The antibiotic doxycycline is an effective alternative, and tends to be well tolerated in most people. Like Malarone it need only be started two days before entering the malaria area. It consists of a daily capsule which needs to be continued for four weeks after leaving the last malaria area. Women taking the pill are advised to use an alternative method of contraception for the first four weeks. Some 1-3% of people taking doxycycline develop an allergic skin reaction in sunlight. The chance of this can be reduced by using a high-factor sunscreen (at least factor 25). If you do develop painful or itchy burning, particularly around the eyes, nose and mouth or backs of the hands, then you should stop taking the doxycycline and seek medical advice as soon as possible. The old alternative of chloroquine (Nivaquine) weekly plus proguanil (Paludrine) daily is rarely given as it is not very effective. It should only be considered as a last resort if nothing else will do.
Prophylaxis does not stop you catching malaria; however it significantly reduces your chances of fully developing the disease and will lessen its severity. Falciparum (cerebral) malaria is the most common in Africa, and usually fatal if untreated, so it is worth your while trying to avoid it.
It is unwise to travel in malarious parts of Africa whilst pregnant or with young children: the risk of malaria in many areas is considerable and such travellers are likely to succumb rapidly.
Because the strains of malaria, and the drugs used to combat them, change frequently, it is important to get the latest advice before you travel. Normally it is better to obtain this from a specialist malaria laboratory or a reputable travel clinic than from your local doctor, who may not be up-to-date with the latest drugs and developments. In the UK, call the recorded message at the Malaria Reference Laboratory in London (tel: 09065 508 908, costs £1 per minute), or see www.malaria-reference.co.uk. In the USA call the Center for Disease Control in Atlanta, Georgia (tel: 770 488 7788 toll free, Mon–Fri 08.00–16.30 eastern time), or see www.cdc.gov.