TROPICAL DISEASES - AFRICA: Information sheet: Travel Health: NEVDGP

Heat and humidity

Excessive heat and humidity, or overexertion in these conditions, may lead to exhaustion from loss of water and salts and to severe heat-stroke requiring emergency medical attention. Tea and drinks rich in mineral salts (fruit and vegetable juices, clear soups, etc.) are recommended in cases of exhaustion Unless contraindicated, the addition of a little table salt to food or drinks helps to prevent heat exhaustion, especially during the period of acclimatisation.
Children and overweight people often suffer from skin irritation (prickly heat). Fungal skin infections such as tinea pedis (athlete's foot) are often exacerbated by heat and humidity. Daily showering, loose cotton clothing and the application of talcum powder to sensitive skin areas will help to reduce these conditions.
Fresh water
Eye, ear, and intestinal infections may be contracted from polluted water. In the tropics, watercourses, canals, lakes, etc. may be infested with larvae that can penetrate the skin and cause schistosomiasis (bilharziasis). Bathing and washing in waters likely to be infested with the snail host of this parasite or contaminated with human and animal excreta should be avoided. Only swimming pools containing chlorinated water may be considered safe for bathing.
"Swimmers Itch" or cercarial dermatitis due to a wide range of trematodes (water parasites) may be acquired in freshwater bodies of both temperate and tropical zones. These cercariae penetrate the skin and die, causing a localised or extended skin allergic reaction. Treatment is symptomatic with eczema preparations.
Bare feet
In areas of known risk, footwear should be worn on land as a protection against worm lavae that can burrow through even the tough skin of the foot (ankylostomiasis, strongyloidiasis, certain mycetomas, and tungiasis.) - also common Cutaneous lava migrans
Schistosomiasis ( bilharziasis )
This is a microscopic skin penetrating parasite disease
Travellers at risk from this infection are those who bathe in streams, rivers, or lakes, or who indulge in water sports in fresh-water areas. Some areas are especially risky; the Nile valley, Lake Victoria, the Tigris and Euphrates river systems, and artificial lakes such as Lake Kariba in Zimbabwe and Lake Volta in Ghana. There is a sign at Lake Malawi that proclaims that it is safe to swim. It definitely is not!
Since the larvae die quickly on removal from water and cannot survive drying, quick drying of exposed skin and clothing does offer some protection. Swimming for short periods in flowing rather than still waters, avoiding the early and late parts of the day, and vigorously rubbing oneself down with a towel immediately after leaving the water may reduce the risk. When schistosomiasis occurs in one or more members of a travelling party, the proportion of those in the party infected is high (between 30% and 60%).
Insect Spread Diseases
Protection against insect bites is important. Many diseases (viruses, parasites and bacteria) are spread by the bites of ticks, sandflies and mosquitoes, which are abundant throughout the region.
Filariasis ( a blood parasite) is confined to the tropics and spread from person to person by insect bites. Travellers have little to fear from this disease, as practically always, the infections, if acquired, are only light and not serious.
Loiasis can be prevented by taking diethylcarbamazine 200 mg daily for three consecutive days each month whilst in heavily infected areas, such as parts of Cameroon. Diethylcarbamazine 300 mg once a week was effective in preventing this infection also. Loiasis is endemic in Cameroon, Central African Republic, Congo, Equatorial Guinea, Gabon, Ghana, Nigeria, and Zaire (NEJM 1988; 319:752-6).
Sleeping Sickness A rare disease in travellers this parasite (trypanosomiasis) is spread by the bite of the tsetse fly and may be a concern to those going on wild life safaris in East Africa, travellers to remote rural areas and those who work with wild animals. Tsetse flies are only active during the day and are attracted by brightly coloured clothing especially blue. Wearing wrist to ankle length clothing, mosquito netting, and knock down insect sprays are recommended. Insect repellents cannot be relied upon but are helpful. Travellers who are likely to spend a prolonged period in an endemic area should seek expert local opinion regarding drug prevention.
Food and Water- borne Diseases
Many forms of worm, parasite and dysentery diseases are highly endemic and advice on selection of food and drinking of water heeded.
Medical Treatment whilst away
Disposable needles, syringes and gloves are available in kits for the traveller. Those contemplating a long stay particularly in remote areas should take these. Kits are also available that contain local anaesthetic, suture material and temporary fillings as well as water purification tablets (puritabs) or filter devices (travel well). TMVC and many chemists provide these.
Current Yellow Fever Infected Areas see www.cdc.gov/travel/outbreaks.htm

Medical Examination after travel: It is advisable (if not essential) to visit your local doctor promptly if you